CHEMICAL ANALYSES  FOR
            WATER QUALITY
 This  course is designed for graduate  chemists and other per-
 sonnel responsible for analytical work in water quality control
 programs.  The course includes a review erf the broad princi-
 ples of water quality management and the interrelationships of
 biological and engineering factors.  This training course man-
 ual has been specially prepared for the trainees attending the
 course and should not  be  cited as a bibliographic reference.
                      Conducted by
    Water Supply and Pollution Control Training Activities
                  TRAINING PROGRAM
U.S. DEPARTMENT OF HEALTH,  EDUCATION,  AND WELFARE
                  Public Health Service
                 Bureau of State Services
       Division of Water Supply and Pollution Control
         Robert A. Taft Sanitary Engineering Center
                  Cincinnati, Ohio 45226
                     January, 1966

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                     TRAINING PROGRAM
     The Public Health Service, U. S. Department of Health, Education,
and Welfare, conducts programs of research, technical assistance,
and training  in environmental h e a 1 1 h at the Robert A. Taft Sanitary
Engineering Center in Cincinnati.   Scientists and engineers in the
Divisions of Water Supply and Pollution Control, Air Pollution, Radio-
logical  Health, and Environmental  Engineering and Food Protection
seek to determine the sources and effects of contamination and to de-
velop new and improved methodology for  the identification, treatment,
and control of causative factors.

     As the national growth accelerates,  problems of the environment
increase both in magnitude and complexity. A concomitant advance in
scientific knowledge results in widespread technological changes.  Pro-
grams in the environmental health field are developing so rapidly that
the call for trained people exceeds the number  available. Although both
public and private agencies are. expanding their training efforts, more
people must be trained in the new technologies if health programs are
to achieve their purpose.
     It is the function and major objective of the Training Program to
provide the specialized training necessary to shorten the gap between
the development  of new technologies  and their application by profes-
sional people  workirig in the field.   The Divisions increasingly utilize
the Training Program for  training new  personnel assigned to  their
many functional areas.
     To meet this objective,  courses are  designed  and conducted by a
full-time staff of experts. Center scientists and engineers and recog-
nized authorities from other government agencies,  universities,  and
industry supplement the training staff by contributing their knowledge
and experience as lecturers  and consultants.
     The courses provide intensive, highly specialized training, usually
at the graduate level.  They are conducted in the Center classrooms
and  laboratories  and at regional locations. Training Institutes, con-
ducted cooperatively with Public Health Service Regional offices,  uni-
versities, and interested agencies, provide a unique means of reaching
large numbers of personnel at one time with joint programs of con-
current courses.
     The Training Program  arranges the schedules of visitors from
foreign countries who come to the Center for training and consultation.
It originated and conducts  the Analytical Reference Service, a cooper-
ative membership  of agencies  concerned with evaluation of environ-
mental laboratory methodologies.
                                             vJO^rux-a ' .
                                        James P. Sheehy,  Director
                                                 Training Program

-------
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-------
                                TRAINING PROGRAM
                               OFFICE OF THE DIRECTOR

                    J.  P.  Sheehy,  Sanitary Engineer Director, Director
                G.  R.  Shultz, Sanitary Engineer Director, Deputy Director
                           R.  N.  Carr, Administrative Officer
                             J. W. Lane, Publications Editor
                   P. F. Hallbach, Biochemist, Laboratory Coordinator
   WATER SUPPLY AND POLLUTION
          CONTROL TRAINING

I. Bernstein, Sanitary Engineer Director, Chief
H. L. Jeter, Bacteriologist, Assistant  Chief
H. W.  Jackson,  Aquatic Biologist
A. G. Jose,  Microbiologist
J.  W. Mandia, Chemist
B. A. Punghorst,  Chemist
P. W.  Weiser, Sanitary Engineer
C. F. L.  Brown, Biologist
       AIR POLLUTION TRAINING

G. W.  Walsh, Public Health Engineer, Chief
S. F. Sleva,  Chemist, Assistant Chief
E. L. Higgins, Chemical Engineer, In Charge,
      Engineering Area
W. H.  Perry, Chemist, In Charge,
      Analytical Area
W. C.  Achinger, Public Health Engineer
R. P. Boksleitner,  Biologist
i. C. Crowe, Physical Scientist
J. L. Dicke,  Meteorologist
J. S. Ferguson, Chemist
T. A. Hackman, Training Instructor
T. A. Hartlage, Chemist
P. W.  Leach, Chemist
3. J. von Lehmden, Chemical Engineer
2. H. Moline, Public Health Advisor
R,. A. Salter,  Chemist
^. E. Spellmire, Engineering Technician
^. T. Shigehara, Chemical Engineer
     FOOD PROTECTION TRAINING

A. B.  Mclntyre, Sr. Sanitarian, Acting Chief
H. L.  Faig, Training Instructor
P. F.  Hallbach, Biochemist
  ENVIRONMENTAL RADIOLOGICAL
          HEALTH TRAINING

R. J. Van Tuinen, Health Physicist, Chief
F. L. Galpin, Sanitary Engineer, Assistant Chief
J. J. Bolen,  Sanitarian
W.  D. Kelley,  Radiochemist
R. E. Landreth,  Sanitary Engineer
B. J. Mann,  Bioradiologist
J. W. Mullins, Radiochemist
R. L. Shearin, Health Physicist
G. H. Simmons,  Health Physicist
R. N. Snelling, Sanitary Engineer
      INTERNATIONAL TRAINING

  H.  W. Jackson, Chief


  ANALYTICAL REFERENCE SERVICE

E. F. McFarren,  Chemist, Chief
R. J.  Lishka, Chemist
J. M. Matthews, Chemist
                      METROPOLITAN PLANNING TRAINING

                  N. E. Tucker,  Sanitary Engineer Director, Chief
                  L. E. Crane, Solid Wastes Consultant
 0. 65

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                                        SPEAKERS
 BALLINGER, DWIGHT G.
 Supervisory Chemist
 Technical Advisory and Investigations Section
 Division of Water Supply and Pollution Control
 5555 Ridge Road
 Cincinnati, Ohio

 BERNSTEIN,  I.
 Chief,
 Division of Water Supply and Pollution Control
 Training Activities
 Training Program, SEC

 BOOTH, ROBERT L.
 Chemist,  Chemistry and Physics Section
 Basic and Applied Sciences Branch
 Division of Water Supply and Pollution Control
 SEC

 BOYLE, HARVEY W.
 Physical Science Technician
 Chemistry and Physics Section
 Basic and Applied Sciences Branch
 Division of Water Supply and Pollution Control
 SEC

 BROWN, CHARLES L.
 Biologist
 Division of Water Supply and Pollution Control
 Training Activities
 Training Program, SEC

 BURTTSCHELL, RICE H.
Chemist,  Chemistry and Physics Section
 Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC

CLARK, ROBERT M.
Mathematician
Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC

JOSE, ALVIN G.
Microbiologist
Division of Water Supply and  Pollution Control
Training Activities
Training Program,  SEC
KAMPHAKE, LAWRENCE J.
Chemist,  Engineering Research Section
Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC

KOPP,  JOHN F.
Spectrochemist, Water Quality Section
Water Pollution Surveillance System
1014 Broadway
Cincinnati, Ohio

KRONER, ROBERT C.
In Charge, General Laboratory Services
Water Pollution Surveillance System
1014 Broadway
Cincinnati, Ohio

LISHKA, RAYMOND J.
Chemist
Analytical Reference Service
Training Program, SEC

LUDZACK, FERDINAND J.
Chemist, Chemistry and Physics Section
Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC

MALOF, NATHAN C.
Chemist
Technical Advisory and Investigations Section
Division of Water Supply and Pollution Control
5555 Ridge Road
Cincinnati, Ohio

MANDIA,  JAMES W.
Chemist
Division of Water Supply and Pollution Control
Training Activities
Training Program, SEC

MATTHEWS, JOHN M.
Chemist, Analytical Reference Service
Training Program, SEC

MCFARREN, EARL F.
Chief, Analytical Reference Service
Training Program, SEC

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                                                                              Speakers
PUNGHORST, BETTY ANN
Chemist
Division of Water Supply and Pollution Control
Training Activities
Training Program, SEC

SHEEHY,  JAMES P.
Director
Training Program, SEC

STEPHAN, CHARLES E.
Chemist, Aquatic Biology Section
Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC
WEISER,  PAUL W.
Sanitary Engineer
Division of Water Supply and Pollution Control
Training Activities
Training Program, SEC

WILLIAMS, ROBERT T.
Leader
Analytical Services Group
Advanced Waste Treatment Research Section
Basic and Applied Sciences Branch
Division of Water Supply and Pollution Control
SEC

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               CHEMICAL ANALYSES FOE WATER QUALITY

                      January 10 - 21, 1966

                             ROSTER
ABERHATHY, LARRY F,
Chemist
Duke Power Company
422 South Church Street
Charlotte, North Carolina
(Fountain Square Hotel)

ALLEN, CBARLSS G,
Chemist
Ohio State Department of Health
382 W. 10th Avenue
Columbus, Ohio

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                             -2-
HjlftTBUN, GEORGB Tn
Assistant Chief Chemist
Interlake Steel Corp*
Ninth & Lowell Streets
Met: port t Kentucky

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                       CHEMICAL ANALYSES FOR WATER QUALITY
                                   January 10-21, 1966
                                         AGENDA
Course
DAY &
Director:
TIME
Monday, January
8:30 -
9:00 -
9:00
9:15
J. W. Mandia

10
Welcome and
Objectives

SUBJECT
Registration
Course Moderators:
OUTLINE
NO.

A
C
.G
.L
. Jose
. Brown
SPEAKER
J.
J.
P.
W.
Sheehy
Mandia
                 I INTRODUCTION
                 A  Water Quality Criteria
 9:30 - 10:15    Water Resources and Needs                      1
10:20 - 12:30    Water Quality Criteria
                   1  PHS Drinking Water Standards               2
                      (10:20 - 11:05)
                   2  Water Quality for Industry, Agriculture,      3
                      Fish,  Wildlife (11:10 - 12:30)
12:30 -  1:30    Lunch
                 B  Data Gathering and Evaluation
 1:30-  2:55    Introduction to Statistical Methods                4
                 (Handout Homework)
 3:00 -  3:45    Quality Control of Chemical Analyses - Part I     5
                                                        P.W. Weiser

                                                        B.A. Punghorst

                                                        J. W. Mandia
                                                        R. M. Clark

                                                        B.A. Punghorst
 3:50 -   4:30
II  ANALYTICAL METHODS
Criteria for Selection of Analytical Methods
J. W.  Mandia
Tuesday, January 11
 8:15-   8:30     Hand in Homework (Statistics)
                 A Oxygen
 8:30 -   9:15     Chemical Measurement of Dissolved Oxygen
 9:30 -  10:15     Electrochemical Measurement of Dissolved
                 Oxygen
                   1  Principles of Polarography
                   2  Dissolved Oxygen Probes
                                                        J. W. Mandia
                                                        J. W. Mandia

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                                        AGENDA
DAY & TIME
                                        SUBJECT
OUTLINE
   NO.
SPEAKER
                                                                        B. A. Punghorst
                                                                        B.A. Punghorst
                                                                        J. W. Mandia
Tuesday, January 11
                B  Oxygen Demand
10:30-  11:20    Principles of Biochemical Oxygen Demand       8        B.A. Punghorst
                (BOD) Test
11:25  -  12:00    Variables of the BOD Test                      8
12:00-  12:30    Briefing for DO,  BOD,  Hardness and Alkalinity,
                Laboratory Experiments and Group Assignments
12:30  -   1:30    Lunch
 1:30  -   4:30    Laboratory
 1:30  -   4:30    Group A N
                Vl_Ga-librate Polarograph for DO              7

                   2   Calibrate Probe for DO                    7
                   3   Set Up 7 Day BOD                         7
                Group B
 1:30  -   3:30    Hardness Determinations                       15
                   1   Calcium and Magnesium
                   2   Presence of Interferences
                                                                        J. W. Mandia
                                                                        N. C. Malof
                                                                        J. W. Mandia
 3:30 -   4:30
                Group C
                Alkalinity Determinations
                   1   Methyl Orange
                   2   Mixed Indicator
                   3   Potentiometer
                Groups B and C
                Hardness and Alkalinity Data
                Problem Session
                                                               14
             B.A. Punghorst
             B.A. Punghorst
Wednesday,  January 12
 8:30 -   9:15     The COD Test COD/BOD Ratios
 9:30 -  10:15     The Carbon Analyzer
                                                               30
                                                                9
                 B Nutrients
10:20  -  11:05     Nutrients in Water - The Problem               10
11:}0  -  11:45     Sources and Determination of Organic Nitrogen   11
11:50  -  12:30     Sources and Determination of Phosphates        12
12:30  -   1:30     Lunch
 1:30  -   4:30     Laboratory
             R. J. Lishka
             R. T. Williams

             A.G. Jose
             F.J. Ludzack
             C. L. Brown

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                                         AGENDA
DAY & TIME
                                         SUBJECT
                                                            OUTLINE
                                                              NO.
SPEAKER
Wednesday,  January 12
 1:30 -   2:00     Group A
                   1   Winkler
                   2   Polarograph
                   3   Probe
 2:00 -   4:00     Alkalinity Determination
                   1   Methyl Orange
                   2   Mixed Indicator
                   3   Potentiometer /'f> ^ r"-A! '"')
 4:00-   4:30     Statistical Calculations
                 Group B
 1:30-   4:30       1   Calibrate Polarograph for DO
                   2   Calibrate Probe  for DO
                   3   Set  Up 7  Day BOD
                 Group C
 1:30 -   4:00     Hardness Determination
                   1   Calcium  and Magnesium
                   2   Presence of Interferences
 4:00 -   4:30     Statistical Calculations
                                                                14
                                                                         J. W.  Mandia
                                                                         B.A.  Punghorst
                                                                         B.A. Punghorst
                                                                 7        J. W.  Mandia
                                                                         N.C.  Malof
                                                                15        J. W.  Mandia
                                                                         B.A.  Punghorst
Thursday,  January 13
                 B  Nutrients (Cont'd)
 8:30 -   9:15     Sources and Determination of Ammonia,
                 Nitrites and Nitrates
                 C Minerals
                                                                13
                                                                         B.A.  Punghorst
9:30 -
10:20 -
11:05 -
11:50 -
12:30 -
1:30 -
1:30 -
2:00 -


10:15
11:00
11:45
12:30
1:30
4:30
2:00
3:30


Measurement of Chlorides, Sulfates,
Alkalinity and pH
Determination of Calcium and Magnesium
Hardness
Flame Photometry
Conductance Measurements in Water
Lunch
Laboratory
Group A BOD 2nd Day
Group B BOD 1st Day
Group A
Hardness Determination
1 Calcium and Magnesium
2 Presence of Interferences
14 J. W. Mandia
15 J. W. Mandia
16 R. J. Lishka
17 J. W. Mandia


J. W. Mandia
15 J. W. Mandia



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                                         AGENDA
DAY & TIME
                                         SUBJECT
OUTLINE
  NO.
                                                            SPEAKER
Thursday,  January 13
 3:30 -   4:30     Problem Session
 2:00 -   4:00     Group B
                 Alkalinity
                   1  Methyl Orange
                   2  Mixed Indicator
                   3  Potentiometer
 4:00 -   4:30     Statistical Calculations
 1:30 -   4:30     Group C
                   1  Calibrate Polarograph for DO
                   2  Calibrate Probe for DO
                   3  Set Up 7 Day BOD
                                                                14
                                                                          B.A. Punghorst
             J. W.  Mandia
                                                                          J. W. Mandia
                                                                          J. W. Mandia
                                                                          N. C. Malof
Friday, January 14
 8:15 -  8:45     Examination (Includes Material Covered During
                 First Week of Course)
                 D   Heavy Metals
                   1  Absorption Spectroscopy
                 Principles of Absorption Spectroscopy
 8:50  -   9:35
 9:50  -  10:30

10:35  -  11:15

11:20  -  12:15
12:15  -  12:30
12:30  -   1:30
 1:30  -   4:30

 1:30  -   2:00
 2:00  -   4:30
 2:00 -   4:30
                 Principles of Metal Chelation in the Colori-
                 metric Determination of Heavy Metals
    18
    19

    20
Determination of Iron and Manganese
  2  Emission Sppctrograph
Use of Emission Spectrograph in Water Analysis 21
Briefing for Lab.
Lunch
Laboratory

Group A BOD 3rd Day
Group B BOD 2nd Day
Group C BOD 1st Day
Groups  A and B\ (B 1 and B2 each 1/2  Group B)
Flame  Photometry                             16
Groups  62  and C
Ion Exchange Fluorides                         25
B.A.  Punghorst
J. W.  Mandia

B.A.  Punghorst

J. F. Kopp
B.A.  Punghorst
                                                                          J. W.  Mandia
                                                                          N.C.  Malof
                                                                          R.J. Lishka
                                                                          J. M.  Matthews

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                                        AGENDA
 DAY & TIME
SUBJECT
OUTLINE
 NO.
SPEAKER
'Saturday. January 15
Time Optional    Group A  BOD 4th Day
                       B  BOD 3rd Day
                   "   C  BOD 2nd Day
                               J. W.  Mandia
Sunday, January 16
Time Optional    Group A BOD 5th Day
                   "   B BOD 4th Day
                   "   C BOD 3rd Day
                               J. W.  Mandia
Monday,  January 17
                   3  Polarograph
 8:30 -   9:30     Polarographic Determination of Cu, Cd,  Ni      22
                 and Zn
                 E  Other Chemicals
 9:45-  10:30     Determination of Phenolics                     23
10:35 -  11:30     Determination of Cyanide                      24
11:35-  12:10     Determination of Fluoride                      25
12:15 -  12:30     Briefing for Fluoride and Flame Photometry
                 Laboratories
12:30 -   1:30     Lunch
 1:30 -   4:30     Laboratory
 1:30 -   2:00     Group A BOD 6th Day
                  "   B BOD 5th Day
                  "   C BOD 4th Day
 2:00 -   4:30     Groups B2 and C
                 Flame Photometry                             16
                 Groups A and B-
                 Ion Exchange Fluorides                        25
                               C.E.  Stephan
                               J. W.  Mandia
                               B.A.  Punghorst
                               J. M.  Matthews
                               J. M.  Matthews
                               R. J. Lishka
                               R. J. Lishka

                               J. M. Matthews
Tuesday, January 18^
 8:30-  9:30    Quality Control of Chemical Analyses-Part II     5
                F  Organic Compounds
 9:45 -  10:30    Trace Organic Contaminants in Water           26
10:35-  11:00    Mathod of Recovery of Organic Contaminants    27
11:00-  11:40    Separation and Identification of Organic          27
                Contaminants
                               B.A.  Punghorst

                               R. L.  Booth
                               R. H.  Burttschell
                               R. H.  Burttschell

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                                         AGENDA
DAY & TIME
                                         SUBJECT
Tuesday,  January 18
ll:4f> - 12:30    Determination of Surfactants
12:30 -  1:30    Lunch
                 Laboratory
                 Group A BOD 7th Day
                       B BOD 6th Day
                    "   C BOD 5th Dpy
                 Groups  A, B ami C
                 The Determination of Nitrates
1:30 -   4:30
1:30 -   2:00
                                                             OUTLINE
                                                               NO.
                                                               28
                                                               13
  SPEAKER
                                                                          A.G.  Jose
                                                                          J. W.  Mandia
                                                                          B.A.  Punghorst
                                                                          J. W.  Mandia
 9:30 - 10:25
10:30 - 11:45
11:45 - 12:30
12:30 -  1:00
 1:00 -
 1:00 -
        4:30
        1:30
Wednesday, January 19
 8:30 -   9:15     Principles of Infrared Spectroscopy
                 Infrared Identification of Organic Compounds
                 Gas Chromatography Lecture and Film
                 Determination of Pesticides in Water
                 Lunch
                 Laboratory
                 Group B BOD 7th Day
                   "   C BOD 6th Day
                 Groups  A and B
                 Infrared Film and Infrared
                 Problem Session
                 Groups  B2 and  C
                 Infrared Instrument
                 Groups  A and B
                 Infrared Instruments
                 Groups  B? and  C'
                 Infrared Film
                 Infrared Problem Session
 3:00 -   4.30
                                                               29
                                                               29
                                                               31
                                                               32
J. W.  Mandia
D.G.  Ballinger
B.A.  Punghorst
B.A.  Punghorst
J. W.  Mandia


B.A.  Punghorst


J. W.  Mandia

J. W.  Mandia

B.A.  Punghorst
Thursday,  January 20
 8:30 -   0:30     Pesticide Film and Discussion
 9:45-  10:30     Quality Control of Chemical Analyses - Part III    5
                                                                         H. W.  Boyle
                                                                         B.A.  Punghorst
                 III  SURVEILLANCE OF WATER QUALITY
10:35-  11:30     PIIS Water Pollution Surveillance System         33
11:30 -  12: )5     Automatic Instrumentation in the Field           34
                                                                         R. C. Kroner
                                                                         D.G. Ballinger

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DAY &

TIME
Thursday, Janu
12:15 -
12:30 -
1:30 -
1:00 -
1:30 -

2:45 -
3:45 -
4:15 -
Friday,
8:30 -
9:15 -
10:50 -
11:35 -
12:30 -
1:30 -
2:05 -
2:35 -
3:00 -
12:30
1:30
4:30
1:30
2:45

3:45
4: 15
4:30
Januar1
9:00
10:45
11:30
12:30
1:30
2:00
2:30
3:00
4:30
AGENDA
SUBJECT OUTLME
:ary 20
Briefing for Laboratory
Lunch
Laboratory
Group C BOD 7th Day
Groups A, B and C
Calculations in BOD Test "K" Rates and L 35
Values (Home Work Calculate Lab. Data)
Atomic Absorption Spectrophotometer 36
Atomic Absorption Demonstration
Course Critique
y_21
Examination (Includes Material Covered During
Second Week of Course)
Automation in the Laboratory 37
Analytical Reference Service 38
Discussion of BOD Laboratory Calculations
Lunch
Discussion of Examination it.> ? r * ^> '*
^ C '-',' "i
Course Summary p ^A ,0 "> '
-,'"' , _ * > '
Course Closing
Visit to Water Pollution Surveillance Laboratories


J.


J.

F.
N.
R.
I.

L.
E.
F.

B.
J.
I.
7
SPEAKER
W. Mandia


W. Mandia

J. Ludzack
C. Malof
J. Lishka
Bernstein

J. Kamphake
F. McFarren
J. Ludzack

A. Punghorst
W. Mandia
Bernstein
Staff

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                                       CONTENTS
Title or Description                                                        Outline Number

Water Resources and Needs                                                        1
Federal Register - Rules and Regulations                                           2
Water Quality Criteria                                                             3
Statistical Analyses of Chemical Data                                               4
Quality Control of Chemical Analyses                                               5
Criteria of Selection of Analytical Methods                                          6
Dissolved Oxygen Determination                                                    7
Laboratory Procedures - Dissolved Oxygen                                         7
Polarographic Analysis                                                            7
Polarographic Determination of Dissolved Oxygen for BOD                           7
Dissolved Oxygen Probe  Laboratory                                                7
BOD Test Procedures                                                             8
Effect of Some Variables on BOD                                                   8
Use of Beckman Carbonaceous  Analyzer for Determining Organic                     9
Carbon in Water
Nutrients  in Water  - The Problem                                                 10
Sources and Analysis of Organic Nitrogen                                          11
Determination of Phosphates in Water                                              12
Determination of Ortho and Polyphosphate by Molybdenum Blue-                     12
Stannous  Chloride Method
Ammonia, Nitrites and Nitrates                                                   13
Ammonia  Determination by Direct Nesslerization                                   13
Laboratory Procedure for Nitrate Modified Brucine Method                         13
Determination of Chloride and Sulfate in Water Supplies                             14
Sulfate                                                                           14
Alkalinity and Relationships Between the Various Types of Alkalinities               14
Alkalinity Laboratory                                                             14
Determination of Calcium and Magnesium Hardness                                 15
Laboratory Procedure for Hardness                                               15
Laboratory Exercise for  the Study of Various Hardness Indicators                   15
Flame Photometry                                                                16
Use of Conductance Measurements in Water Analysis                                17

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                                                                                 Contents
Title or Description                                                         Outline Number

Principles of Absorption Spectroscopy                                               18
Metal Complexes and Chelates in the Colorimetric Determination                     19
of Metals
Iron and Manganese in Water                                                       20
The  Determination of Total Iron by the Phenanthrolme Method                        20
The  Determination of Manganese by Periodate Oxidation                              20
Principles of Emission Spectroscopy                                                21
The  Polarographic Determination of Copper, Cadmium,  Nickel,                       22
and Zinc
The  Determination of Phenols                                                       23
Laboratory Exercise  - Analysis of  Waste Sample for Phenol                          23
Sources, Effects and  Analysis of Cyanides                                           24
Laboratory Procedure for  Cyanide                                                   24
Recent Advances in Estimating Fluorides in Water                                   25
Laboratory Procedure for  Fluoride                                                  25
Trace Organic Contaminants in Water                                               26
Methods of Recovering Organic Materials from Surface Waters                       27
Preliminary Separation of  Extracts                                                  27
Procedures for the Preliminary Separation of Extracts                               27
Surfactants and Synthetic Detergents                                                 28
Infrared Instrumentation                                                            29
Infrared Identification of Organic Compounds                                         29
Chemical Oxygen Demand and COD/BOD Relationships                               30
Laboratory for Chemical Oxygen Demand Determination                              30
Introduction to Gas-Liquid Chromatography                                          31
Pollution Problem of  Pesticides                                                     32
Basic Data for Water Supply  and Water Pollution Control                             33
Operations of the Water Pollution Surveillance System                                33
Automatic Instruments for Water Quality Measurements                              34
Mathematical Basis of the  Biochemical Oxygen Demand (BOD) Test                    35
Estimation of K and L                                                              35
Atomic Absorption Spectrophotometry                                               36
Automation of Chemical Analysis                                                    37
Analytical  Reference  Service                                                        38

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                              WATER RESOURCES AND NEEDS

                                  Edward D.  Schroeder*
 I  WATER RESOURCES
 A  The source of all freshwater is the
    hydrologic cycle.

    1  Precipitation of water as rain, snow,
       hail, sleet or dew.

    2  Percolation of water through soil to an
       aquifer to form groundwater.

    3  Runoff of water which forms lakes,
       streams and rivers.

    4  Evaporation of surface  water or
       transpiration of water from green
       plants to  the atmosphere.

    5  Atmospheric recirculation of the water
       vapor.
      b The geography of the region

      c The general climate of the area.


   2  U. S. areas of high annual precipitation

      a The Pacific slope varies from 10
        inches to greater than 100 inches
        annually.

      b The gulf states precipitation varies
        from 20  to 60 inches annually.

      c Precipitation in the midwest and
        Great Lakes area ranges from 25  to
        50 inches per year.

      d Precipitation along the Atlantic Coast
        averages between 35 and 50 inches
        per year.
 B  The volume of water in the hydrologic
    cycle is fixed.

    1  Average precipitation in the U. S.  is
      30 inches per year or 3, 900 billion
      gallons per day.

    2  Evapo-transpiration losses total
      approximately 21 inches per year or
      approximately 2, 740 billion gallons per

    3  The  available water totals approximately
      9 inches per year or  1J60  billion gallons
      per day.
II   THE DISTRIBUTION OF U.S. WATER
    RESOURCES
 A  Distribution of Precipitation

    1  Dependent  upon:

      a  Atmospheric conditions such as
         temperature and winds.
   3  Areas of low annual precipitation

      a The Rocky Mountain area precipitation
        ranges between 10 and 20 inches per
        year.

      b Much of the southwest has less than
        10 inches of precipitation annually.
   4  Distribution of precipitation with time

      a  The rainy or wet season varies from
        summer to winter, or in  some areas
        there is relatively little change through-
        out the year.

      b  Local storms of high intensity may
        reach as much as 30 inches in 24 hours.
B  Distribution of Runoff

   1   Dependent upon:

      a  Precipitation in the region
*Former Public Health Engineer, DWS&PC Training Activities and revised by Peter F. Atkins, Jr.
Former SA Sanitary Engineer, DWS&PC Training Activities, SEC.  Reviewed December  1965.
W.RE.28b. 11.64                                                                        1-1

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Water Resources and Needs
        Infiltration - which is controlled by
        the geologic formations and the time
        lapse between rains.

        Season of the year controls
        evaporation.

        Topography controls the time
        available to percolate through the
        soil.
   2  Areas of high annual runoff

      a  Sections of the Pacific slope have
         greater than 80 inches annually.

      b  The eastern  1/3 of the U.S.  averages
         greater than 20 inches of runoff
         annually.
   3  Much of the western U. S.  has less than
      1 inch of runoff annually.

      a  Southwest

      b  Rocky Mountain states

      c  Rocky Mountain plateau


C  Distribution of Groundwater

   1  Groundwater volume is affected by the
      same factors as runoff.

   2  Geologic formations and soils control
      percolation and storage of groundwater.

   3  Topography controls time available for
      percolation.

   4  Evapo-transpiration varies with the
      season,  as does precipitation and
      ground saturation.
Ill  WATER USE


 A Present Water Use in the U. S.

    1  Water available for use

       a  Nine inches or 1,160 billion gallons
          per day are not lost through evapo-
          transpiration,  and is  therefore
          theoretically available.

       b  Water use in the U. S.  at the present
          time is  approximately 390 billion
          gallons  per day or 3 inches of our
          total supply.

       c  Twenty-one inches  are lost through
          evapo - transpiration.


    2  The way in which water is used

       a  Agricultural uses take 46% of our
          supply  or 180 billion gallons/day; only
          40% of  this water is returned to the
          streams.

       b  Industrial uses take another 46% of
          our supply.   2% of the water used by
          industry is consumed.

       c  Municipal uses total approximately
          25 billion gallons daily or 8% of the
          total.

    3  Source of  water used in U. S.
          National averages show 80% or
          312 billion gallons per day to
          be from surface sources, while
          is taken from the ground.
20%
          The ratio of surface water to ground-
          water varies and is dependent on the
          quantity and quality available in each
          locality,  as well as the cost.
1-2

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                                                              Water Resources and Needs
   4  Seasonal uses of water

      a  Irrigation waters are used during
         the growing season only.

      b  Some water using industries such
         as the canning industry are
         seasonal.

      c  The majority of industries needs
         water throughout the year.

      d  Municipal use is higher in the
         summer.
B  Demand for water is increasing.

   1  The predicted demand of water in 1980
      is approximately 600 billion gallons of
      water per day,  or 220,000 billion per
      year.
   2  This is mainly due to expansion of
      industry and irrigated agriculture.

   3  Much of the demand for water will be
      in areas such as the southwest, that
      are  already short on water.
C  Methods for the Development of U. S.
   Water Resources for Future Needs

   1   Utilization of our present sources of
      water,  surface and groundwater, must
      be increased.  This would mean in-
      creased storage, both on the surface
      and in underground reservoirs.

    2 Desalinization of ocean waters and
      brackish waters holds some promise
      for regions where transportation will
      not be expensive.

    3 Reduction  of evapo-transpiration losses
      will greatly increase our total available
      supply.

    4 Weather modification methods could
      possibly give us precipitation in the
      right place at the right time.

    5 Greater reuse of our present  supply is
      both through multiple use and better
      waste treatment methods.
IV  SUMMARY

 The total amount of water available appears
 to be fixed.  In view of the increasing demands
 and the currently inefficient utilization of
 the supply, the demand may very shortly
 exceed the supply.   Better management of
 the resource  and more engineering research
 is urgently needed.
                                                                                       1-3

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Water Resources and Needs
                      Table 1.  AVAILABILITY OF GROUND WATER
Areas
A
B
C
D
E
F-l
F-2
G
Atlantic and Gulf Coastal Plain area
Southern Great Plains area
Appalachian Mountain and Piedmont area
Rocky Mountains, northern Great Plains,
and northern Pacific Coast area
Unglaciated central plateaus and lowlands
Basin and range
Columbia Plateau
Glaciated area of the East and Midwest
U. S. total (rounded)
Water Use
(excluding water power)
Use in mgd and Percent
of Total From
Ground Water Sources
Total
mgd
32,000
21,000
8,000
28,000
26,000
41,000
24,000
57,000
240,000
Ground
water (%)
25
45
50
12
10
42
7
10
20
REFERENCES

1  Ackerman, Edward A.,  Lof, George O.G.
      Technology in American Water
      Development.  The Johns Hopkins Press.
      Baltimore.  1959.

2  Senate Select Committee on National
      Water Resources:  Water Resources
      Activities in the United States: Com-
      mittee  Print No. 3.   U.S. Gov.  Printing
      Office. January 1960.
3  Senate Select Committee on National Water
     Resources:  Water Resources Activities
     in the United States: Committee Print
     No.  24.  U.S. Gov. Printing Office.
     January 1960.

4  Linsley,  Ray K. , Kohler, Max A.,
      Paulttus, Joseph H.  Hydrology for
      Engineers.   McGraw Hill Book Co.,
      Inc.  New York.   1958.
 1-4

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        Taemlay,  March  6,  1962
                                FEDERAL REGISTER
                                                                                                             2152
                                             RULES  AND  REGULATIONS
   Title  42 PUBLIC  HEALTH

Chapter  I Public   Health  Service,
   Deportment  of Health, Education,
   and  Welfare

PART 72 INTERSTATE QUARANTINE

     Drinking  Water Standards
  On July 27,  1961. notice  of proposed
rule  making  relating  to  the revision of
the  regulations  in  this Subpart J 
Drinking  Water  Standards, and  a  re-
lated section was published  In the FED-
ERAL REGISTER  (26 F.R. 6737).   After
consideration of all relevant matter pre-
sented  legarding the  proposed revision,
the  regulations  as   so  published are
adopted, to become effective 30 days after
the  publication of this notice  in the
FEDERAL REGISTER, subject to the changes
>et out below
  1  Section 72203; The words "Figure
i   are  added  Immediately  below the
jiaph in this section.
  2  Section  72205(l>:  The   word
fluoride"  Is  substituted for the  word
'flouridc"  appearing  In the  table  In
   3  Section 72 205(b> (2) : The concen-
tration in nig/1  for  chromium (Hexa-
valent) shown in the table is amended to
read "0 05"
   4. Paragraph      of  1 72.206  Is
amended
   Dated: February 21, 1962.
   (SEAL)
LUTHER L. TERRY,
  Surgeon General.
   Approved: February 28, 1962.

     ABRAHAM RiBicorr,
       Secretary.

 ' 72.1   | Amendment]

   1  Section 72.1(1)  Is amended to read:

   < 1)  Potable   water.  Water  which
 neets the  standards prescribed in the
 ^ublic Health  Service  Drinking Water
 Standards  (see Subpart J of this part).

   2  Bubpurl J  is amended  to read as
 'ollows

 iiibpart JDrinking Water Standard*

 iec
 '2 301  Definition of term*.
 '2 202  Source and  protection.
 '2 1'O.t  lJatt<-rlologlcal quality.
 1 'M-\  1'hysltal  characteristics.
 2 '-!U6  Chemical characteristic*.
 3 2U6  Radioactivity
 2 207  Recommended analytical method*.
  Atirrronmr: 1)72201  to  73307  luued
 inder nee 315, 6B btnt 680. aa amended; 41
 ISC  216   Interpret* or applle* MO. 361,
 H Htut 703,  42 USC. 264
 72.201   Definition* of terms.
  As used hi this subpart, the following
terms shall have the meanings set out
below:
  (a) "Adequate protection by  natural
means" Involves one or more of  the fol-
lowing processes of nature that produce!
water consistently meeting the  require-
ments  of  these Standards:  dilution,
storage, sedimentation, sunlight,  aera-
tion, and  the  associated physical and
biological processes  which tend to ac-
complish natural purification In surface
waters and, in the case of ground wa-
ters, the natural purification of water by
Infiltration  through  soil and  percola-
tion through  underlying material and
storage below the ground water  table.
  (b) "Adequate protection  by treat-
ment"  means any one or any combina-
tion of the controlled processes of coagu-
lation, sedimentation, absorption, filtra-
tion,  disinfection,  or  other  processes
which  produce  a   water  consistently
meeting   the   requirements   of  these
Standards    This protection also In-
cludes  processes which are appropriate
to the souice  of supply; works which
are of  adequate capacity to meet maxi-
mum demands without creating health
hazards,  and   which  are  located, de-
signed, and constructed to eliminate or
prevent  pollution;  and  conscientious
operation by well-trained and competent
personnel whose qualifications are com-
mensurate with  the  responsibilities of
the position and acceptable  to  the re*
porting agency and the certifying au-
thority.
  (c) "Certifying Authority" means the
Surgeon  General of the United States
Public Health  Service  or his duly au-
thorized  representatives  Reference  to
the  certifying   authority is  applicable
only for  those  water supplies to be cer-
tified for use on carriers subject to this
part
   (d)  "The collform group" Includes all
organisms considered  In the   collform
group  as set forth In Standard Methods
for  the   Examination of  Water and
Wastewater, current  edition,  prepaied
and published  jointly by the Ameiican
Public  Health Association,  American
Water Works  Association,  and Water
Pollution Control Federation.
   (e)  "Health  hazards" mean any con-
ditions, devices, or practices In the water
supply system  and Its operation  which
create, or  may create, a danger to the
health and well-being of the water con-
sumer   An example of a health hazard
is a structural defect  in the water sup-
ply system, whether of location, design,
or construction, which may regularly or
occasionally prevent satisfactory purifi-
cation of the water supply or cause it to
be polluted from extraneous sources.
    "Pollution",  as  used  In  these
Standard*, means the  presence of any
foreign substance  (organic,  Inorganic,
radiological,  or  biological)  In  wuter
which tends to degrade its quality so as
to constitute a hazard or Impair the use-
fullness of the water.
   (g)  "Reporting agencies" means  the
respective official State health agencies
or their designated representatives.
   (h)  "The standard sample"  for  the
bacteriological test ahal] consist of:
   (1) For the bacteriological fermenta-
tion tube test, five (6) standard portions
of either:
   (1) Ten mllllllters  (10 ml)
   (ID  One hundred  mllllllters (100 ml)
   (2) For  the membrane  filter  tech-
nique, not less than fifty mllliliters  (50
ml).
   (D "Water  supply system" includes
the works and auxiliaries for collection,
treatment, storage, and distribution  of
the water from  the  sources of suply to
the free-flowing  outlet of the ultimate
consumer.
 72.202  Source and  protection.
   (a) The water supply should be ob-
tained from  the  most  desirable  source
which is feasible, and  effort should  be
made to prevent  or control pollution of
the source.   If the  source  Is not ade-
quately protected by natural means, the
supply shall be adequately protected  by
treatment.
   (b) Frequent  sanitary  surveys  shall
be made of  the water supply system  to
locate and Identify health hazards which
might exist In the system.  The manner
and frequency of making  these surveys,
and the rate at which discovered health
hazards are to be removed shall be  in
accordance with a program  approved  by
the reporting agency and the certifying
authority.
   (c) Approval of water  supplies shall
be dependent In part upon:
   (1) Enforcement of rules and regu-
lations to prevent development of health
hazards;
 A/S. ST. dr. 2.2.63
                                                                                                           2-1

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Tuesday, March 6,  1962
                                             FEDERAL REGISTER
                                2153
  (2) Adequate protection of the water
quality throughout all parts of the sys-
tem, as demonstrated by frequent sur-
veys;
  (3) Proper operation of the water sup-
ply system under the responsible charge
of personnel whose qualifications are ac-
ceptable  to  the reporting  agency and
the certifying authority;
  (4) Adequate capacity to meet  peak
demands  without  development  ol low
pressures  or other health hazards; and
  (5) Record  of  laboratory examina-
tions  showing consistent   compliance
with the water quality requirements of
these Standards.
  (d) For the purpose of application of
these Standards,  responsibility  for the
conditions in  the water supply  system
shall be considered  to be held by:
  (1) The water  purveyor  from  the
source  of supply  to the connection  to
the customer's service piping; and
  (2)  The owner of the property served
and the municipal, county, or other au-
                                    thority  having  legal  Jurisdiction from
                                    the point of connection to the customer's
                                    service piping to the fi-c^-flowing outlet
                                    of the ultimate  consumer.

                                     72.203  Barleriologir"! quality.
                                      (a) Sampling.  (1)  Compliance  with
                                    the bacteriological requi-ements of these
                                    Standards shall be  basnd on examina-
                                    tions of samples collected at representa-
                                    tive  points throughout the distribution
                                    system.   The frequency of sampling and
                                    the  location  of sampling points shall
                                    be established jointly by  the reporting
                                    agency and the certifying authority af-
                                    ter investigation  by either  agency,  or
                                    both, of the source, method of treatment,
                                    and  protection  of the water concerned.
                                      (2) The  minimum  number of sam-
                                    ples to be collected from the distribution
                                    system and examined each month should
                                    be in accordance with  the number  on
                                    the graph In Figure I, for the population
                                    served by the system.  For the purpose
                                    of uniformity and simplicity In  applica-
                           NUMBZR or
                                                           MONTH
    JJtMJXM
*v*4A*
 2-2
                  N
                                                        1
                                                         \
                                                             r
                                  FIGURE I.
tlon, the number determined from the
graph, should be In accordance with, the
following: For a population of  25,000
and underto  the nearest 1;  25,001 to
100,000to  the nearest  5;  and over
100.000to the nearest 10.        ^
  (3)  In  determining  the  number  of
samples examined monthly, the  follow-
ing samples may be included, provided
all results are  assembled  and  available
for inspection and the laboratory meth-
ods and technical  competence  of the
laboratory  personnel  are approved  by
the reporting agency and  the certifying
authority;
  (1)  Samples examined by the  report-
Ing agency.
  (11) Samples examined  by local gov-
ernment laboratories.
  (til)  Samples examined by the water
works authority.
   When 100 ml standard portions
are examined, not more than 60  percent.

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2154
     RULES AND REGULATIONS
In any  month  shall show  the  presence
of the collfonn group.  The presence of
the -conform group In all five of  the
100 ml  portions of  a standard sample
shall  not  be allowable If this occurs:
  (1)  In two consecutive samples;
  (1H In  more than one  sample  per
month when leu than five are examined
per month; or
  (111) In more than 20 percent of  the
samples when five or more are examined
per month.
When organisms of the collform group
occur In all five of the 100 ml  portions
of a single standard sample, dally sam-
ples from the same sampling point shall
be collected promptly and examined un-
til the results obtained from at least two
consecutive samples show  the water to
be of  satisfactory quality.
  (3)  When the membrane Alter  tech-
nique Is used, the arithmetic mean coll-
form density of all standard samples ex-
amined  per month shall not exceed one
per   100   ml.  Collform  colonies  per
standard  sample shall  not exceed 3/50
ml. 4/100  ml, 7/200 ml, or 13/500 ml in:
  (I)  Two consecutive samples;
  (11) More than one standard sample
when less than 20 are examined  per
month;  or
  (ill) More than  five percent of  the
standard  samples when 20 or more  are
examined per month.
when collform colonies in a single stand-
- d sample exceed the above values, daily
samples from  the  same sampling  point
shall be collected promptly and examined
until  the  results obtained from  at least
two consecutive samples show the water
to be  of satisfactory quality.
 72.204  Thyrtical characteristic*.
  (a)  Sampling.  The  frequency  and
manner of sampling shall be determined
by the reporting agency and the  certi-
fying  authority. Under normal  circum-
stances  samples should be  collected one
or more times per week from represent-
ative  points In the  distribution system
and   examined for   turbidity,   color,
threshold odor, and taste.
  (b)  Limits.   Drinking water should
contain no impurity which would  cause
offense  to the  sense  of sight,  taste,  or
smell.  Under general use,  the following
limits should not be  exceeded:
  Turbidity8 unit*.
  Color15 unite.
  Threahold odor number3.
 72.205  Chemical characteristics.
  (a)  Sampling.   (1)  The frequency
and manner of sampling shall be deter-
mined by the reporting agency and  the
certifying authority.  Under normal cir-
cumstances,  analyses  for  substances
listed  below need  be made only  semi-
annually.   If,  however, there  is  some
presumption of unfltness because of  the
presence of undesirable elements,  com-
pounds,  or materials,  periodic  deter-
minations for the suspected toxicant or
material should he made more frequent-
ly and  an  exhaustive  sanitary survey
should be made to determine the source
of the pollution.  Where the concentra-
tion of  a substance is  not expected to
Increase in processing and distribution.
available  and acceptable source water
analyses performed In accordance with
standard  methods may be used as evi-
dence of compliance with these Stand-
ards.
  (2)  Where  experience, examination,
and  available  evidence Indicate that
particular substances are consistently
absent from a water supply or below
levels of concern, semi-annual examina-
tions  for  those  substances  may  be
omitted when approved  by  the report-
ing agency and the certifying authority.
  (3)  The burden  of  analysis may be
reduced in  many cases  by using data
from  acceptable  sources.   Judgment
concerning the quality of water  supply
and  the  need for performing  specific
local  analyses may depend In part on
information produced by such agencies
as (1) the U.S. Geological Survey, which
determines chemical quality of surface
and ground waters of the United States
and publishes these data  In "Water Sup-
ply Papers" and other reports, and (11)
the U.S.  Public  Health  Service which
determines water quality related tojpol-
lutlon (or the absence of pollution) in
the principal  rivers of the  Nation and,
publishes  these data  annually in "Na-
tional Water  Quality  Network."  DatJ
on pollution of waters as measured
carbon chloroform extracts  (CCE) mi
be found  In the latter publication.
  (b)  Limits.  Drinking  water shall nol
contain   Impurities  In  concentratlons>
which may  be hazardous to  the  health
of the consumers.  It should not be ex-
cessively corrosive to the water  supply
system.   Substances used  in Its treat-
ment  shall not remain in the  water in
concentrations greater than required by
good  practice.  Substances  which may
have deleterious physiological effect, or
for which physiological  effects are not
known, shall not  be introduced into the
system in a  manner which would permit
them  to reach the consumer.
  (1)  The  following   chemical  sub-
stances should not be present in a water
supply In  excess of the listed concentra-
tions where, in the Judgment of the re-
porting  agency and the certifying au-
thority,  other more suitable  supplies are
or can be  made available.
                          Concentration
           Substance         (n my It
Alkyl Benzene Sulfonatc (ABB)	   0.6
Arsenic (Ae)	   0.01
Chloride  (Cl)-	--	250
Copper (Cu)		   1.0
Carbon Chloroform Extract  (CCE)..   0 2
Cyanide  (CN)			   0.01
Fluoride  (F).--	 ()
Iron  (Fe)-			   0.3
Manganese (Mn)	   0.05
Nltrnte'  (NO,)		  45
Phenols	..-	   0 001
Sulfnte (SO,)	--		250
Total Dissolved Solids	500
Zinc  (Zn)		   5
  See 72 205(b) (3).
  ' In areas in which the nitrate content ol
water IB  known to  be In exceu of  the listed
concentration, the  public should be warned
of the potential danger* of using  the water
for Infant  feeding.

  (2>  The  presence  of the  following
substances In excess  of  the  concentra-
tions  listed  shall  constitute  grounds for
rejection of the supply:
                          Concentration
           Subttanc*         In my/1
Arsenic  (A*)	_.	  0.05
Barium  (Ba)		  1.0
Cadmium  (Cd)	  0.01
Chromium (Hexaralant)  (Cr+)	  O.OB
Cyanide  (ON)	  0.2
Fluoride  (P)	  ()
Lead (Pb)._			  0. OS
Selenium (8e)	  0.01
Silver (A)	  0.06
  See 72206(b)<3).

  (3Hi)  When  fluoride   is  naturally
present in drinking water, the concen-
tration  should not average more than
the appropriate upper limit In Table I.
Presence of fluoride in average concen-
trations greater than  two times the op-
timum values  In Table I shall constitute
grounds for rejection  of the supply.
  (11) Where fluoridatlon (supplementa-
tion of fluoride in drinking water)  la
practiced, the average fluoride concen-
tration  shall be kept within the upper
and lower control  limits In Table I.
                TABU I
                                     \
t A nmml average o(
! mailmum dally air
temperature* 
SO.O-S3.7 	
M.S-S8.3 	
68.4-63.8
M.9-708 	
70 7-711.2
79.3-905 	
y
Recommended Control LUnlU
(Fluoride concentration* In mj/i)
Lower
0. 
0.8
O.g
0.7
07
04
Optimum
l.J
1.1
10
0 
0.8
0.7
Upper
I
o. sL
 > Based on temperature data obtained for a mlnlmu J
of five years.                           /

   (ill) In addition to the  sampling re-
quired by paragraph  (a) of this section,
fluoridated  and  defluoridated supplies
shall be  sampled  with sufficient  fre-
quency to determine  that the desired
fluoride concentration is maintained.
 72.206 . Radioactivity.

   (a)  Sampling.  (1) The  frequency of
sampling and analysis for radioactivity
shall be  determined by the reporting
agency  and  the certifying  authority
after  consideration  of  the  likelihood
of  significant  amounts  being present,
Where  concentrations of Ra-226  or
8r-80 may vary  considerably, quarterly
samples composited over a period of three
months are recommended.   Samples for
determination  of gross activity  should
be taken and analyzed more frequently.
   (2) As Indicated In |72.205(a).  data
from acceptable sources may be used to
Indicate  compliance with these require-
ments.
   (b)  Limits.  (1) The effects of human
radiation exposure are viewed as harm-
ful and  any unnecessary   exposure  to
ionizing  radiation  should   be avoided,
Approval of  water supplies containing
radioactive materials shall be based upon
the Judgment that the radioactivity In-
take  from  such  water  supplies  when
added to that from all other sources Is
not likely to result in an Intake greater
than the radiation protection guidance '
  'The Federal  Radiation Council, In It*
Memorandum for the President, September 
13.  1061. recommended that "Boutin*  con-
trol of useful application* of radiation and
atomic energy should be *uch that expected
                                                                                                              2-3

-------
Tuetday, March 6, 1962
         FEDERAL  REGISTER
                                 2155
recommended by. the. Federal Radiation
Council and .approved by  the President.
Water supplies shall be approved with-
out  further  consideration  of  other
sources of radioactivity  Intake  of  Ra-
dlum-226  and  Strontlum-90 when the
water  oontalna  these  substance* in
amounts not exceeding 3 and 10 p/ic/llter,
respectively.  When these concentrations
are exceeded, a water  supply  shall be
approved  by  the certifying authority If
surveillance of  total Intakes of  radio*
activity from  all sources  Indicates  that
such Intakes are within the limits  rec-
ommended  by'  the  Federal  Radiation
Council for control action.
  (2) In the known absence' of Stron-
tlum-90 and alpha emitters, the water
supply Is acceptable when the gross  beta
concentrations do not exceed 1,000  MMC/
liter.  Oross beta concentrations In ex-
cess of 1,000 Mpo/liter shall be grounds for
rejection  of supply  except  when more
complete analyses Indicate that concen-
trations of  nuclidea  are  not likely to
cause exposures greater than the Radia-
tion Protection  Guides as approved by
average exposures of suitable samples of an
exposed population group will not exceed the
upper value of Range II (20 *c/day of Ra-
dium- * and 200 **c/day of Strontlum-BO)."
   At   i i U taken here to mean a negligi-
bly Eina . traction of the above specific limit*,
where the limit for unidentified alpha emit-
ters U taken as the listed limit for  Radlum-
236.
the President on recommendation of the
Federal Radiation Council.
| 72.207  Recommended analytical
    methods.
  (a)  Analytical  methods to determine
compliance  with the  requirements of
these  Standards shall be those specified
In Standard Methods for the Examina-
tion of Water and Wastewater. Am.  Pub.
Health Asaoc., current edition and those
specified as follows:
  (1)  Barium: Methods for the Collec-
tion and  Analyses  of  Water Samples,
Water Supply Paper  No. 1454.  Rain-
water, F. H.  ft  Thatcher.  L.  L.,  U.S.
Geological Survey, Washington, D.C.
  (2)  Carbon   Chloroform  Extract
(CCE): Manual for Recovery and Iden-
tification  of   Organic  Chemicals In
Water, Mlddleton, F. M, Rosen, A. A.,
and Burttschell,  R. H., Robert A.  Taft
Sanitary Engineering Center, PHS,  Cin-
cinnati, Ohio.
  (3)  Radioactivity: Laboratory  Man-
ual   of  Methodology,  Radlonucllde
Analyses  of  Environmental  Samples,
Technical  Report  R59-6.  Robert A.
Taft Sanitary  Engineering Center, PHS,
Cincinnati, Ohio,  and Methods of Radio-
chemical Analysis, Technical Repo-t No.
173. Report  of  the  Joint  WHO-FAO
Committee,  1959, World Health Organi-
sation.
  (4)  Selenium:   Suggested  Modified
Method for  Colorimetrlc Determination
of Selenium  la  Natural Water, Magln.
O. B., Thatcher, L. L.. Rettlg.  8., and
Levlne, H.. J. Am. Water Works Assoc.
52. 1109 (1000).                   J
  (b> Organitmt of  the coliform group.
All  of the detail* of techniques In  the
determination of bacteria of this group,
Including  the selection and preparation
of apparatus and media, the  collection
and  handling of samples and the Inter-
vals and conditions of storage allowable
between collection  and examination of
the water  sample, shall be In accordance
with Standard Methods for the Exami-
nation of  Water and Wastewater,  cur-
rent edition, and the procedures shall be
those specified therein for:
  (1) The Membrane Filter Technique
Standard  Test, or
  (2) The Completed Test, or
  (3) The Confirmed Test, procedure
with brilliant green lactose bile  broth,'
or
  (4) .The Confirmed Test, procedure
with Endo or eosin methylene blue aear
plates.1
                                                                               (P.R,  Doc.
           83-2181; Filed,
              8:40 am.)
Mar. 8,  1983;
  The Confirmed Test Is allowed, provided
the value of this test to determine the sani-
tary quality of the specific water supply
being examined Is established beyond rea-
sonable  doubt  by  comparisons with Com-
pleted Tests performed on the same water
supply.
   2-4

-------
                                WATER QUALITY CRITERIA

                                        J.  W. Mandia*
The chemical analysis of water in a large part
determines the beneficial use of a given body
of water.  The beneficial uses  include water
supplies for drinking,  industry, irrigation,
stock and \\ildlifc and fish and  aquatic life.

Thr chemicals present and physical state of
\vator\vlricb effect its use include:  suspended
solids,  dissolved solids,  temperature, hard-
ness, phenol, cyanides,  nitrates, sulfates,
zinc,  copper, iron,  lead,  nickel,  manganese,
magnesium,  selenium,  and boron.
I  SUSPENDED SOLIDS

A  Source

   In natural waters, suspended solids consist
   normally of erosion silt, organic detritus
   and plankton.

15  Effects On Beneficial Uses

   1   Domestic  water supplies

      The 10G2 PHS drinking water standards
      do not specify limiting concentration for
      suspended solids.  It is controlled by
      the limits on turbidity,  5 units, and
      total  solids (500 mg/1).   It has been pro-
      posed thai for drinking water of ideal
      quality,  suspended matter should be
      limited to 0. 1 mg/1 or less.

   '.'.  Industrial water supplies

      Suspended solids cause  foaming in
      boilers, incrustation on equipment ex-
      posed to water.  They are undesirable
      in \\aler for textile industries, paper
      and pulp,  beverages,  dairy products,
      cooling systems and power plants and
      \\ater for  steel manufacturing.

    i  Irrigation water

      Paperboard mill wastes  containing
      240 mg/1 of suspended solids have been
       successfully used for spray irrigation
       of alfalfa.

    4  Fish and aquatic life

       a  Suspended solids may kill fish and
         shellfish and various aquatic fauna
         by clogging the gills and respiratory
         passages.

       b  Suspended solids blanket the stream
         bottom, killing eggs, young and
         food organisms and destroying
         spawning beds.

       c  They screen out light (turbidity).
         It is recommended that all cellulose
         pulps and sawdust be excluded from
         streams.

       d  It is also recommended that mineral
         suspended solids be so finely divided
         as to pass through a 1000-mesh
         screen, and that the stream bottom
         not be blanketed to a  depth of more
         than one-quarter inch.
II   DISSOLVED SOLIDS

 A  Source

    Dissolved solids consist mainly of carbon-
    ates, bicarbonates, chlorides, sulfates,
    phosphates and possibly nitrates of calcium,
    magnesium, sodium and potassium, with
    traces of iron and manganese.

 B  Effects On Beneficial Uses

    1   Domestic water supplies

       PHS drinking water standards specify
       that the total dissolved solids should not
       exceed 500 mg/1.  This limit was set
       primarily on the basis of taste thres-
       holds.  Higher  concentrations may be
       consumed without harmful physiological
       effects.
 Chemist, DWS\PC Training Activities, SEC.  Reviewed December 1965.
\\ .(-<>. (.. J 1. H4
                                                                                       3-1

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                                                                    Water Quality Criteria
 2  Industrial water supplies

    Dissolved solids cause foaming in boil-
    ers and interfere with clearness, color,
    taste of many finished products.

 3  Irrigation water

    It has been considered that 1000 mg/1
    is a concentration which approaches the
    limit for  best crop growth.  Irrigation
    waters  in California have  been classi-
    fied according to salt content as follows:
                        Concentration mg/1

                            175 or less

                            175 -   525

                            525 -  1400

                           1400 -  2100

                           2100 or more
Classification

 Excellent
 Good
 Permissible
 Doubtful
  Injurious


   4  Stock and wildlife

      A maximum permissible concentration
      of dissolved solids in water of 2500 rng/l
      has been recommended.

      In Montana,  livestock standards are;

      Good            2500  - 3500 mg/1

      Poor             3500 - 4500 mg/1

      Unsatisfactory    4500 mg/1 over

   5  Fish and aquatic life

      The blood of freshwater fishes has an
      osmotic pressure approximately equal
      to six atmospheres or about 7000 mg/1
      as sodium chloride.

      In practical  pollution work, any  effluents
      with an osmotic pressure  greater  than
      six atmospheres, may be  expected to be
      deleterious  to freshwater  fish.

      Fish in waters  of low salinity cannot
      survive  sudden exposure to high salin-
      ities,  such as those resulting from dis-
      charge of oil well brines.
       Dissolved solids may influence the
       toxicity of heavy metals and organic
       compounds to fish and other aquatic life
       because of the antagonistic  effect of
       hardness metals.

    6  Summary

              Use         Dissolved Solid Mg/1

       Domestic Water Supply    1000  mg/1

                                  700  mg/1

                                 2500  mg/1

                                 2000  mg/1
Irrigation

Stock watering

Freshwater fish
III  HARDNESS

 A Source

    Hardness in water may be caused by the
    natural accumulation of salts from contact
    with soil and geological formations,  or it
    may enter from direct pollution by indue -
    trial wastes.

  R Effects On Beneficial Uses

    1  Domestic water supplies

       In good water,  the total hardness is
       usually below 250 mg/1.  Hardness
       above 500 mg/1 is considered unsuit-
       able for general domestic purposes.
       The  major detrimental effect of hard-
       ness is ecomonics.

       The  annual cost of cleansing agents for
       a family of five,  doubles  as the hardness
       increases from zero to 375 mg/1.  It
       has  been found that the savings for soap,
       syndets, scouring coumpounds, bleaches,
       were $1. 15 per capita per year for each
       100  mg/1 reduction in  hardness.

    2  Industrial water

       Excessive hardness is undesirable in
       water for laundries, carbonated bever-
       ages, metal finishing,  dyeing and textile,
       food, paper and pulp,  etc.
3-2

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                                                                      Water Quality Criteria
    3  Irrigation

       Hardwater is superior to soft water for
       irrigation.

    4  Fish and aquatic life

       In hard waters, toxic metals may be
       less dangerous.
2  Industrial water supplies

   a  Water for barley malting should have
      a temperature of about 12C.

   b  Water temperature for use in dairy
      factories should be 16C or less.

   c  Water temperature for use in steel
      mills should be below 24C.
IV  TEMPERATURE

 A  Source

    Temperature changes in bodies of water
    may result from natural climatic phenomena
    or from the introduction of industrial
    wastes.  Temperature is important and
    sometimes critical for many uses of water.

    Increased temperature may cause decreas-
    ed oxygen capacity, increased oxygen de-
    mand,  putrefaction of sludge deposits, and
    growth of sewage fungus.  Stream temper-
    ature may also be increased by irrigation.

    Increases in temperature of return water
    of from 100 to 20C have been reported.

 B  Effects On  Beneficial Uses

    1   Domestic water supplies

       a Water temperature of 10C is usually
         satisfactory for drinking purposes.
         Temperatures of 15C or higher are
         usually  objectionable.

       b The efficiency of water purification
         and treatment is  better in warm
         rather than in cool water.

       c Chlorination is more effective in
         summer than in winter.

       d The alum dose,  however, required
         to reduce the color of raw water was
         observed to be  as much as two times
         greater at 14 - 24C than at 8  - 14C.

       e Bactericidal effects of disinfectants
         are generally increased by an increase
         in temperature of water.
   d  Streams have lost their value for
      cooling purposes as the water temp-
      erature rises as much as 27C
      during the course of discharge and
      reuse of the water by  many indust-
      ries in succession.

   e  Warm water causes corrosion in
      pipe lines and cooling systems.

3  Irrigation water

   Below 10C,  water weeks grow very
   sparsely; between  10  - 15C growth
   is prolific.

4  Fish and aquatic life

   a  Warm temperatures reduce solu-
      bility of dissolved oxygen, increases
      metabolism, respiration and oxygen
      demand of fish.

   b  Toxicity of many substances is
      intensified as the temperature rises.

   c  There is  a maximum temperature
      that each species of fish can tolerate.

   d  ORSANCO has recommended that
      waste discharges be so controlled
      that the temperature of receiving
      water not be raised  about 34C at
      any one place and not  above 23C at
      any place during months of December
      through April, and not be raised at
      all in streams suitable for trout
      propagation.
                                                                                        3-3

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Water Quality Criteria
V  PHENOL

A  Source

   Phenolic wastes arise from the distillation
   of wood, from gas works,  coke ovens,  oil
   refineries,  chemical plants, sheep dips
   and from human and animal refuse.

B  Effects  On Beneficial Uses

   1   Domestic water supplies

      PHS  drinking water standards limit the
      concentration of phenolic compounds to
      0.001 nig/1 because of the tastes re-
      sulting from the action  of chlorine on
      phenolics in water.

   2  Industrial water supplies

      Phenol is deleterious in many of the
      food  and beverage industries and may
      cause obnoxious tastes  and odors.

   3  Irrigation

      Phenol in irrigation water is not  consid-
      ered to be deleterious to crops.

   4  Stock and wildlife

      Appreciable concentrations  of phenol
      are not toxic to animals.

   5  Fish and aquatic life

      a  Information relating to pure phenol
         indicates that  24, 48 and 96 hour
         TL m concentrations are  in the gen-
         eral range of 10 -20  mg/1 at 2QOC.
         Phenol appears to act as a nerve
         poison,  causing too  much blood to
         get to the gills and to the heart cavity
         of the fish.

      1)  Threshold responses to phenol occurs
         in the vicinity of 1.0 mg/1.

      c  Chlorophenols produce a bad taste in
         fish flesh even at concentrations far
         below lethal or toxic doses.
    6  Summary

          Supply

       Domestic
       Irrigation
       Livestock
Phenol Concentration

     0.001 mg/1
    50.0   mg/1
  1000.0   mg/1
       Fish and Aquatic Life   0. 20   mg/1
VI  CYANIDES

  A Source

    Cyanide occur in effluents from gas works
    and coke ovens, from the scrubbing of
    gasses  at steel plants, from, metal clean-
    ing and electroplating processes and from
    chemical industries.  HCN is largely an-
    dissociated at pH values of 8 and less.

  B Effects On Beneficial Uses

    1  PHS drinking water standards set a
       recommended limit of 0.01 mg/1 and a
       mandatory limit of 0. 02 mg/1.  The
       odor threshold for HCN  in water is
       0.001 mg/1.  The CN ion is changed
       rapidly to the relatively non-toxic
       sulfur compley (SCN) thiocyanate in the
       liver.

    2  Industrial water  supplies

       No information regarding industrial
       water.

    3  Irrigation

       No information regarding effects of
       cyanide on irrigation water.

    4  Fish and aquatic life

       a  The  toxicity of CN" is affected by
          pH and temperature - a rise of  10C
          produces a two to three-fold increase
          in the rate of lethal action.
  3-4

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                                                                         Water Quality Criteria
           Nickel may complex with cyanide to
           reduce lethality,  but zinc and
           cadmium cyanide complexes are
           exceedingly toxic.

           Cyanide inhibits oxidase responsible
           for the transferring of oxygen from
           the blood.
VII  NITRATE

  A  Source

     In spite of their many sources, nitrates
     are seldom abundant in natural surface      VIII
     waters for they  serve as an essential fertil-
     izer for all types of plants from phytoplank-
     ton to trees.   Photosynthetic action is
     constantly utilizing nitrates and converting
     them to organic nitrogen in plant cells.

     In ground waters (absence of photosynthesis)
     excessive and deleterious concentrations
     of nitrates are often found.

  B  Effects On Beneficial Uses

     1   Domestic  water supplies

        PHS recommended a limit of 45 mg/1
        nitrates, NO  (10 mg/1 NO   - N).  It
        has been widely recommended that water
        containing more than 10 mg/1 of nitrate
        nitrogen should not be  used for infants.

        Nitrates are  rated among the poisonous
        ingredients of mineralized waters,  with
        potassium nitrate being more poisonous
        than sodium nitrate.  Excess nitrates
        cause irritation of the  mucous linings of
        the gastrointestinal tract and bladder.

     2  Industrial water supplies

        Nitrates and  free nitric acid at concen-
        trations of 15 to 30 mg/1 render water
        harmful for various industrial purposes.

     3  Irrigation

        Nitrates are  desirable for their fertiliz-
        ing value.
   4  Stock and wildlife

      Special attention should be paid to the
      concentration of nitrates in stock
      waters, especially when total salt con-
      centration exceeds 570 to 1000 mg/1.

   5  Fish and aquatic life

      By increasing plankton growth and the
      development of fish food organisms,
      nitrates indirectly foster increased
      fish production.
   SULFATES

A  Source

   Sulfates occur naturally in waters, partic-
   ularly in the Western United States, as a
   result of leachings from gypsum and other
   common minerals.  It occurs as the final
   oxidized stage of sulfides, sulfites and
   thiosulfates.

   Iron pyrite FeS may be leached from
   abandoned  coal mines  and the sulfide ions
   converted in surface streams to sulfates.

   Sulfates may be discharged in numerous
   industrial wastes such as those from
   tanneries,  sulfate-pulp mills,  textile mills.

B  Effects On Beneficial Uses

   1  Domestic water supplies

      The PHS 1962 drinking water standards
      recommend 250 mg/1.

   2  Industrial water supplies

      Sulfates increase the corrosiveness of
      water toward concrete.

   3  Irrigation

      a Sulfates are somewhat less toxic
        than  chlorides in irrigation waters.

      b Sulfates can cause the precipitation
        of calcium and may be toxic to plants.
                                                                                          3-5

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 Water Quality Criteria
         The sulfates present in excellent
         irrigation waters is less than 192
         mg/1 and in water unsuitable for
         irrigation, over 960  mg/1.

    4  Stock and wildlife

      Cattle that drank water  containing 3590
      mg/1 and 2104 mg/1 of sulfate died.  A
      threshold  limit of 1000 mg/1 has been
      suggested.

    5  Fish and aquatic life

      In the  U. S. 95% of the waters that
      support good game fish  contain less than
      90 mg/1 sulfate.

    6  Summary

      It appears that the following concentra-
      tion of sulfates will not  be detrimental
      for the indicated beneficial use:
        Domestic Water Supply    500 mg/1

        Irrigation                 200 mg/1

        Stock Watering            500 mg/1
         physiological effects upon man
         except at very high concentrations.

      b  At a concentration of 30 mg/1 zinc
         gives a milky appearance and causes
         a greasy film on boiling.

   2  Industrial water supplies

      Zinc-bearing water should not be used
      in acid drinks like lemonade,  because
      zinc citrate and other organic  zinc
      compounds that will result may be
      poisonous.

   3  Irrigation

      Small amounts of zinc are needed for
      nutrition by most crops, but toxicity
      results when concentration exceeds a
      very low level.

   4  Fish and aquatic life

      It is toward fish and aquatic organisms
      that zinc exhibits its greatest toxicity.
      In soft water,  concentrations  of zinc
      ranging from 0.1 to 1.0 mg/1 have been
      reported to  be lethal.
IX  ZINC

 A  Source

    Zinc occurs abundantly in rocks and ores.
    It is used extensively for galvanizing,  in
    alloys, for electrical purposes, in print-
    ing plates,  for dye-manufacturing.  Zinc
    salts are used in paint pigments, cosmet-
    ics, pharmaceutics, dyes, insecticides.

    In zinc mining areas, zinc has been found
    in natural waters in concentrations as high
    as 50 mg/1 in effluents from metal-plating
    works.

 B  Effects On  Beneficial Uses

    1  Domestic water  supplies

      a  The taste threshold for zinc occurs
         at about  5  mg/1.  Zinc has no adverse
X  COPPER

/\  Source

   Copper salts occur in natural surface
   waters only in trace amounts,  up to about
   0.05 mg/1 so that their presence is gener-
   ally the result of pollution.  Copper salts
   are used in textile processing, tanning,
   electroplating,  insecticides and fungicides.

B  Effects On Beneficial Uses

   1  Domestic water supplies

      The limiting  factor in domestic water
      supplies  is taste.  Threshold concen-
      trations for taste have been generally
      reported in the range of  1.0 -  2.0 mg/1
      of copper, while as much as 5 -7.5
      mg/1 makes the water completely un-
      drinkable.
  3-6

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                                                                       Water Quality Criteria
     2  Industrial water supplies

       In food-preserving industries, copper
       causes undesirable color reaction,
       forming tannates and sulfides.  Traces
       of copper in metal-plating baths affect
       the smoothness and brightness of the
       metal deposits.

     3  Irrigation

       Minute quantities of copper are bene-
       ficial or essential for plant growth.

     4  Fish and aquatic life

       The sulfate of copper and zinc,  copper
       and cadmium are synergistic in their
       toxic effect of fish.  Copper is concen-
       trated by plankton by factors 1000 to
       5000.  Copper  concentrations as low as
       0. 1 to 0. 5 have been reported toxic to
       bacteria and other micro-organism.
       Copper  concentrations as low as 0.01
       to 0. 5 mg/1 have interferred with BOD
       determinations.
    5  Summary

               Use
         Domestic supply

         Irrigation
         Fish and aquatic life

          Freshwater
          Seawater
Recommended
Copper Limit
1.0 mg/1

0. 1 mg/1


0.02  mg/1
0.05  mg/1
XI  IRON
 A Source
    In addition to corrosion products, natural
    water may be polluted by iron-bearing
    industrial wastes; pickling operations,
    acid mine drainage. Ferrous ions are
    readily oxidized in natural surface waters
    to the ferric condition and form insoluble
    hydroxides.  In well-aerated waters,  the
    concentration of iron is seldom high.  In
    ground  waters, the pH and Eh may be such
    that high concentration of iron remain in
    solution.
                     B  Effects On Beneficial Uses

                        1   Domestic water supplies

                           The taste threshold of iron in water
                           has been given as 0. 1 mg/1 FeSO.  and
                           0.2 mg/1 Fe2(S04)3

                        2   Industrial water supplies

                           0.1 to 0. 2 mg/1 of iron recommended.

                        3   Irrigation

                           It is generally of little importance  in
                           irrigation practice.
XII LEAD

    A  Source

       The characteristics of water,  soft or hard,
       that appear to be conducive to lead - sol-
       vency include comparative absence of
       calcium and bicarbonates, low pH, high
       dissolved oxygen and high nitrate content.
       Owing to the fact that  the carbonate and
       hydroxide are insoluble and the sulfate is
       only sparingly solube,  lead will not remain
       long in natural waters.

    B  Effects On Beneficial  Uses

       1  Domestic water supplies

         Lead is a cumulative poison.   It tends
         to be deposited in bone.  The PHS
         mandatory limit for lead is 0, 05 mg/1.
         The U.  S, Government has also estab-
         lished a tolerance of lead in food at
         7 mg/kg,  more than 100 times  the
         limit for drinking water.

       2  Industrial water supplies

         Traces  of lead in metal-plating baths
         will affect the smoothness and bright-
         ness of deposits.

       3  Irrigation

         Lead is apparently  toxic to plants.
                                                                                        3-7

-------
   Water Quality Criteria
      4  Stock and wildlife

         It is not unusual for cattle to be poisoned
         by lead in water.  Chronic lead poisoning
         among animals has been caused by 0. 18
         mg/1 of lead in soft water; 0. 5 nig/1 of
         lead is the maximum safe limit for lead
         in water  for animals.

      5  Fish and aquatic life

         In water  containing lead salts, a film of
         coagulated mucus,  first forms over the
         gills, and then over the whole body of
         the fish.   The death of the fish is caused
         by suffocation due to this obstructive
         layer.  Calcium in a concentration of
         50 mg/1 has destroyed the toxic effect
         of 1. 0 mg/1 of lead.

         The dissolved content of surface waters
         should be restricted to  0. 1 mg/1 for
         drinking  water and for fish and aquatic
         life.
XIII  NICKEL

    A Source

      Many nickel salts are highly soluble in
      water and since they are used in metal-
      plating works they may be discharged to
      surface or ground waters.

      Metallic nickel does not merit serious con-
      sideration as  a water pollutant, but nickel
      ions may be detrimental to beneficial  uses.

    B Effect On Beneficial Uses

      1  Domestic water supplies

         Toxicity of nickel to man is believed to
         be very low.

      2  Irrigation

         Nickel is extremely toxic to  citrus
         plants.
     3  Stock and wildlife

        Nickel appears to be less toxic to fish
        than copper or zinc.

        Nickel combines readily with cyanide
        to form a nickel-cyanide complex that
        is relatively stable.  In acid waters,
        however, the complex breaks down and
        releases HCN.
XIV   MANGANESE

   A  Source

      Like iron it occurs in the divalent and
      trivalent form.  The chlorides,  nitrates
      and sulfates are highly soluble in water;
      but the oxides,  carbonates  and hydroxides
      are only sparingly soluble.

      For this reason, manganic or manganous
      ions are seldom present  in natural surface
      waters in concentrations above 1 mg/1.

      In ground water subject to reducing con-
      ditions, manganese can be  leached from
      the soil and occur in high concentration.

   B  Effects On Beneficial Uses

      1   Domestic water supplies

         PHS drinking water standards set a
         recommended limit of manganese of
         0. 05 mg/1.   This limit is based on
         esthetic and economic considerations
         rather than physiological hazard.

         It causes unpleasant tastes, deposits
         on food during cooking,  stains and
         discolors laundry and plumbing fixtures.

      2   Industrial water  supplies

         Excessive  manganese is undesirable in
         water for use in many industries in-
         cluding textiles,  dyeing, food processing,
         etc.

-------
                                                                        Water Quality Criteria
     3  Irrigation
       Manganese is essential for plant growth,
       apparently as an enzyme activator.
     4  Stock and wildlife
       Manganese is important in the nutrition
       of livestock being closely related to that
       of calcium, phosphorus,  iron, copper.
     5  Fish and aquatic life
       The permanganates are  much more toxic
       to fish than the manganous salts.
u se
                             Concentration of
                                Manganese
         Domestic water supply    0.05 mg/1
         Industrial water supply   0.05 mg/1
         Irrigation                0.50 mg/1
         Stock and wildlife        10.0  mg/1
         Fish and aquatic life      1.0  mg/1

XV MAGNESIUM
 A Source
    One of the most common elements in the
    crust of the earth is magnesium, about
    2. 1% of earth's crust.  With the exception
    of the hydroxide at high pH values,  its
    salts are very  soluble.  Its carbonate will
    dissolve to the extent of 100 to 300 mg/1.

 pH
  X  10     at 18C
   Solubility of
Magnesium ion,  Mg
7
10
11
1200 moles/1
1. 2 moles/1
0.012 moles/1
28,800 g/1
28.8 mg/1
0. 288 mg/1
 B Effects On Beneficial Uses
    1     Domestic water supplies
          At high concentrations, magnesium
          salts have a laxative effect.
                                      2  Industrial water
                                         Industry
                                         Brewing
                                         Soda pulp
                                         Sugar making
                                         Textile manufacturing
                                 Limit of
                                   Mg
                                 30 mg/1
                                 12 mg/1
                                 10 mg/1
                                  5 mg/1
XVI  SELENIUM
   A  Source
      Selenium is  used in a variety of industrial
      applications, such as pigmentation in
      paints, dyes and glass production and in
      electrical apparatus.  Selenium is highly
      toxic to iflan^ symptoms^ are similar to
      tho s e_o j
                                   B Effect On Beneficial Uses
                                      1  Domestic water supplies
                                         PHS drinking water standards has a
                                         mandatory limit of 0. 01 mg/1.
                                      2  Industrial water
                                         No information
                                      3  Irrigation
                                         The classification of irrigation water
                                         based on selenium concentration is as
                                         follows:
                                      Irrigation
                                        class
                                      low
                                      medium
                                                       high
                                      very high
                                                                       Selenium
                                                                       mg/1
                                  Remarks
                                                                      0. 00-0. 10  no plant toxicity
                                                                      0.11-0.20  usable, but with
                                                      0.21-0.50
                     over 0. 50
                                                        long term accum-
                                                         ulation
                                                         toxic accumu-
                                                         lation in plants
                                                         non-usable under
                                                         any condition
                                                                                         3-9

-------
   Water Quality Criteria
      4  Stock and wildlife

         Selenium poisoning causes..''alkali
         dise_agG_a.^Ii.n-rl-s.ta.ggEJZg- " It occurs
         naturally among  cattle,  sheep,  horses,
         pigs, in both chronic and acute form.

         In water 0.4 to 0.5 mg/1 of selenium,
         it is believed to be non-toxic to cattle.
         Selenium content of feed is a more
         critical factor.

      5  Fish and aquatic life

         It is believed that selenium is passed up
         through the food  chain to the fish which
         accumulate this  element in the liver in
         lethal concentrations.
  2  Irrigation

    Boron is  an essential element in the
    nutrition  of higher plants, yet concentra-
    tions in excess of 0. 5 mg/1  may be
    deleterious for certain crops.

  3  Stock and wildlife

    The lethal dose of boric acid for animals
    varies  from 1.2 to 3.5 grams per kg of
    body weight.
   4  Fish and aquatic life

      Boric acid can be toxic.
XVII   BORON

    A  Source

       Boron occurs as sodium borate (borax) or
       as a calcium borate in mineral deposits
       and natural waters of Southern California
       and in Italy.  Boric acid and boron salts
       are used extensively in industry for weather
       proofing wood,  fire proofing fabrics and
       manufacturing glass and porcelain.

    B  Effects On Beneficial Uses

       1 Domestic water supplies

         Boron in drinking water is not  generally
         regarded as a hazard to human beings.
REFERENCES

1  Standard Method for the Examination of
     Water and Wastewater.  llth Edition.
     1960.

2  Water Quality Criteria.  McKee and Wolf.
     2nd Edition.   The Resources Agency of
     California.  State Water Quality Control
     Board,  Sacramento,  California.
      3-10

-------
                        STATISTICAL ANALYSIS OF CHEMICAL DATA

                                         J. A.  Bell*
  I  DEFINITIONS

  A The single values which can be computed
    from a series of observations  and which
    summarize the information contained in
    these observations are called statistics.

  B Statistical analysis is a mathematical
    method for drawing conclusions from the
    results of experiments.
 II  THE CONCEPTS OF NORMAL DISTRI-
    BUTION AND CENTRAL TENDENCY

 A In a group of results, the plot of the
    magnitude of the measurements against
    the frequency of their occurrence de-
    scribes the Gaussian or normal dis-
    tribution curve.
          Magnitude of Measurements
Figure 1. NORMAL DISTRIBUTION CURVE
                                         (1)
                                                  Figure 2.  ALKYL BENZENE SULFONATE
                                                    WATER SURFACTANT NO. 2 -  1963
                                                                ( 57 Results)
      One of the assumptions most frequently
      made  in statistics problems is that the
      observations describe this normal
      curve.

      Moderate departures  from normality
      do not seriously affect the validity
      of many of the statistics based on
      normal distributions.

      a  An example of a  normal distribution
         curve drawn from  an Analytical
         Reference Service  (ARS) study.
                                                           .35    .40   .45   .50
                                                               RESULTS  (mg I)
.55   .60   .65
                                                  B  The tendency of observations to cluster
                                                     at some particular location on the scale
                                                     of measurement used is called  the
                                                     "central tendency. "
                                                     1
                                                         The statistic most commonly used to
                                                         measure this central tendency is the
                                                         arithmetic mean or average.

                                                         a  The formula for the mean is:

                                                         where    E  X.  =  X  +X.. + ...+ X
                                                                 n = number of observations
                                                         The second measure, known as the
                                                         median, is simply the middle value
                                                         of a distribution,  that is,  the quantity
                                                         above which half, and below which the
                                                         other half of the data lie.

                                                         If N data are  ranked in their order of
                                                              .^  ,   .,     ,.   .  .,    N + 1th
                                                         magnitude, the median is the  s
*Former Statistician,  Analytical Reference Service, Training Program.  Revised by  R.T.
Statistician, Analytical Reference Service, Training Program. Reviewed December 1965.
                                                                                          Cope,
 ST. 22b. 11.65

-------
 Statistical Analysis of Chemical Data
       value.  If the number of data is even,
       then the numerical value of the median
       is the value midway between  the two
       data nearest the middle.
       ~,
     / The median is less influenced by extreme^
     (^values in a distribution than the mean.    J

    3  Another measure of central tendency
       is used in more  specialized applications.
       The antilog of the mean of the logarithms
       of a set of data is called the geometric
       mean.  It is most often used  for data
       whose  causes  behave  exponentially,
       rather than linearly.  One example is
       the growth of bacteria.  The  geometric
       mean  is numerically equal to the Nth
       root of the  product of the  N data, but
       computation is most easily done by
       way of logarithms.
 Ill THE MEASUREMENT OF THE DISTRI-
    BUTION OF RESULTS OR VARIABILITY

 A The Standardized Normal Curve
  -5-4-3-2-10    1    2   3    4    5
Figure 3. STANDARD NORMAL DISTRIBUTION*1'
     1  The equation of the normal curve is:
       Y  =
where  cr  =  standard deviation of the
            distribution

       (i  s  mean of the distribution

       X  =  the abscissa, the measure-
            ment or score marked on
            the horizontal axis.

       Y  = the ordinate,  the height of
            the curve corresponding to
            an assigned value of X

2  The standardized normal curve has
   [i "  0, a  1; therefore, its  equation
       Y  =
3  The characteristics of a normal curve
   are:

   It is symmetric around the mean.

   It extends without limit to the left and
   right and approaches the x axis rapidly
   as we move from the mean; but it
   never reaches the x axis.  (X would
   have to equal + )

   The total area under the curve is  1.

4  The mean fixes the location  of the
   center of the curve with reference to
   the x axis.

5  The standard deviation  describes  the
   spread or distribution of data along
   the x axis.

   a  The formula for standard deviation
      is:

 4-2

-------
                                                   Statistical Analysis of Chemical Data	
      b  The variance -  cr  (or) S-
B  Formulas for Standard Deviation

   1  For an infinite population and for a
      sample.

      a  For an infinite population
               s (x.  - p.)
                                        _ 2
        The sum of the squares, 2(Xi - X)
        from the mean of a sample is less   _
        than the sum of the squares, ^(X^ (j.) ,
        from the mean of an infinite population.
        Therefore,  a smaller denominator
        ( n-1) is used and the  formula is:
                  (X.  - X)
                   (n - 1)~
        For an actual sample s is used to de
        note standard deviation, and X, the
        mean; cr  is used to denote standard
        deviation and \i, the mean,  only in
        the ideal case when an infinite popu-
        "lation is available.
          The range as a measure of
          variability.

          Despite the existence of a computa-
          tional formula for the standard
          deviation, the easiest way to obtain
          a measure of dispersion of a set of
          data is to find the difference between
          the maximum and the minimum  data
          in the set.  This  simple measure is
          appropriately termed the range.
          Obviously the range does not make
          full use of the information  contained
          in the data,  since only two of the data
          are taken into account.  The range
          is however reasonably efficient
          compared to s when the number of
          data is  10 or less. Thus the range
          is an extremely handy measure of
          variability for small samples
          (N< 11).
IV  COMPUTATIONAL EXAMPLES OF
    CENTRAL TENDENCY AND VARIABILITY

 A Computation of the mean.  Consider the
    following simple set of data.
   2   For use on a calculator

      a  Although the defining formula  for
        the standard deviation gives insight
        into its meaning, an algebracially
        equivalent ^omputational formula
        makes computation much easier for
        any normal distribution:

          ,     nZ X.2  - (S X.)2
          ^  _       i          i
                   n (n - 1)
        Using this formula it is necessary
        merely to array the data in a
        column, construct another column
        of squared data,  and find the sums
        for both columns ( note that sum X^
        does NOT equal (sum X.)2) .
    First, let us calculate the mean.  The
    sum of the data is 8,  so the mean equals
    sum X
      N      "

 B Next, the median.  First, rank the data,
    thus, 0,  1,  3,  4.  Since there is an even
    number of data, the median will lie between
    the two middle data,  and the median is
    2.0.

 C Let us now recall that the geometric mean^
    is best calculated by means of logarithms.

       log   4 =  0.602
       log   1 =  0.000
       log   3   0.477
       log   0 =  does  not exist; therefore
                  we cannot calculate the geo-
                   metric mean of these data.
                                                                                        4-3

-------
Statist leal Analysis of Chemical Data
   If the 0 datum were a  1 instead,  the sum
   of the logs would be 1.079, and the average
   logarithm 0.270, which yields a geometric
   mean of 1. 86.

D Now let us calculate statistics of variability
   for our original set of data.

   1  The range.  Since the  size of this data
      sample  is small, the range is a useful
      measure of variability, and its  calcu-
      lation here is exceedingly simple:
      Range =4-0 = 4.

   2  The standard  deviation.  First, let us
      try to apply the  definitional formula.
      We array the  data in a column,
                                        ,2
      data

       4
       1
       3
       0

   sum X

       X
       deviations

          +2
          -1
          +1
          -2
(X. - X)

   4
   1
   1
   4

10 =  X.
        i
=  2
              10
      Now, the computational formula,
                   ,2
                  X.
       4
       1
       3
       0
   sum X.
       16
        1
        9
        0
       26
               2          2
       N sum X  - (sum X) __
       ~~  N (N - 1)
                    4(26) - 64 _ H)
                       4(3)     "  3
      Here the differences in difficulty of com-
      putation between the methods are not so
      marked as they would be for a larger set
      of data.
 normal distribution curve for which
 M-  - 0 and a  -  1.

 We can measure the area and the number
 of ff 's within which X% of the area of the
 normal curve is contained.

 Therefore,  we can say for an interval of
 a given number of o-'s  on the standardized
 normal curve, which contains X% of the area
 of the curve,  in the same interval of o-'s on
 the frequency vs. magnitude curve, X% of
 the results  will be contained.

 For a normal distribution the interval
 /
 ';    M.  + lo-    contains 68. 3% of the area
 /               under the  normal curve
     H  + 2cr    contains 95.5% of the area
                under the  normal curve
     H  + So-    contains 99. 8% of the area
                under the  normal curve
VI  PARAMETERS USING STANDARD
    DEVIATION

 A Confidence  Limits

    1  Definition

       Confidence limits are the end-points
       of the range within which we would
       expect to find the true mean with a
       given probability.
                    2  The formula:

                          C.L.  =  X +
                         t s
                       //n"1
                       where X = the mean
                             s  = standard deviation

                             n  = number of observations

                             t  = is the value for a given pro-
                                  bability in Student's t tables. *
                                  (Table 1)
V   USE OF THE STANDARDIZED
    NORMAL CURVE
 The plot of results of an ideal experiment by
 frequency vs.  magnitude gives the standardized
                                        *If a table other than the one given in this
                                        outline is used,  check carefully as to which
                                        column gives a desired confidence  level.
 4-4

-------
                                                            Statistical Analysis of Chemical Data
                   TABLE 1.   PERCENTAGE POINTS OF THE t-DISTRIBUTION*
\
\^,
V**
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
40
60
120
OO
ompute
ction, "
QC
0.50
^
1.00000
0.81650
0.76489
0.74070
0.72669
0.71756
0.71114
0.70639
0.70272
0.69981
0.69745
0.69548
0.69384
0.69242
0.69120
0.69013
0.68919
0.68837
0.68763
0.68696
0.68635
0.68580
0.68531
0.68485
0.68443
0.68405
0.68370
0.68335
0.68304
0.68276
0.68066
0.67862
0.67656
0.67449

0.25

2.4142
1.6036
1.4226
1. 3444
1.3009
1.2733
1.2543
1.2403
1.2297
1.2213
1.2145
1.2089
1.2041
1.2001
1. 1967
1. 1937
1. 1910
1. 1887
1. 1866
1. 1848
1. 1831
1. 1816
1. 1802
1. 1789
1. 1777
1. 1766
1. 1757
1. 1748
1. 1739
1. 1731
1. 1673
1. 1616
1. 1559
1. 1503
	 	
0. 10

6. 3138
2.9200
2.3534
2. 1318
2.0150
1.9432
1.8946
1.8595
1.8331
1.8125
1.7959
1.7823
1.7709
1.7613
1.7530
1.7459
1.7396
1.7341
1.7291
1.7247
1.7207
1.7171
1.7139
1.7109
1. 7081
1. 7056
1.7033
1.7011
1.6991
1.6973
1.6839
1.6707
1.6577
1.6449
d by Maxine Merrington from "Tables
Biometrika, 32
(1941), pp.
168-181,
0.05
12.706
4. 3027
3. 1825
2.7764
2.5706
2.4469
2. 3646
2.3060
2.2622
2.2281
2. 2010
2. 1788
2. 1604
2. 1448
2. 1315
2. 1199
2. 1098
2. 1009
2.0930
2. 0860
2. 0796
2.0739
2.0687
2.0639
2. 0595
2.0555
2.0518
2.0484
2.0452
2.0423
2.0211
2.0003
1.9799
1.9600
0,025
25.452
6.2053
4. 1765
3.4954
3. 1634
2.9687
2.8412
2. 7515
2.6850
2. 6338
2.5931
2.5600
2.5326
2.5096
2.4899
2.4729
2.4581
2.4450
2.4334
2.4231
2.4138
2.4055
2. 3979
2. 3910
2. 3846
2.3788
2. 3734
2.3685
2. 3638
2. 3596
2. 3289
2.2991
2.2699
2.2414
0.01
63.657
9.9248
5.8409
4.6041
4.0321
3.7074
3.4995
3. 3554
3.2498
3. 1693
3. 1058
3.0545
3.0123
2.9768
2.9467
2. 9208
2.8982
2.8784
2.8609
2.8453
2.8314
2.8188
2.8073
2.7969
2. 7874
2.7787
2. 7707
2.7633
2.7564
2. 7500
2. 7045
2.6603
2.6174
2.5758
0. 005
127.32
14.089
7.4533
5.5976
4.7733
4.3168
4.0293
3.8325
3.6897
3.5814
3.4966
3.4284
3.3725
3.3257
3.2860
3.2520
3.2225
3. 1966
3. 1737
3. 1534
3. 1352
3. 1188
3. 1040
3.0905
3.0782
3.0669
3.0565
3.0469
3.0380
3.0298
2.9712
2.9146
2.8599
2.8070
 by permission of Professor E. S. Pearson.
   A description of this table is given in Section 4.54.  Where necessary, interpolation should
 be carried out using the reciprocals of the degrees of freedom.  The function  120 jv is  con-
 vie nt for this purpose.
**v - (n-1)  (Ref. 1)
                                                                                        4-5

-------
  Statistical Analysis of Chemical Data
  B Coefficient of Variation

    1  Definition

       This is the standard deviation expressed
       as a percentage of the mean, i.e., it
       tells what percent the  standard deviation
       is of the  mean.

    2  The formula:
       Coefficient of variation = v = 100


       where X  =  mean
              s  =  standard deviation
X
                 If  T  =  the true value

                    X  =  the value obtained
                          expe rimentally

                    E  =  the error

               Then T  =  X  + E

                 If  E  =  O, then T = X and the measure-
                          ment is accurate
               2  Precision is a measure of the repro-
                 ducibility of the measurement or how
                 closely the  measurements correspond
                 to one another
VII THE CONCEPTS OF ACCURACY
    AND PRECISION

  A Definitions

     1  Accuracy is the correctness of a
       measurement or how  closely the result
       corresponds to the true value.
               3 In the following graph the observations
                 were fairly precise but not accurate:
                                               IRON
                                     AMOUNT ADDED  0.62 MG/L
                               AVERAGE AMOUNT RECOVERED  0.44 MG/ L
                                         AMOUNT ADDED
                  MEAN
               mill
mi IIII
                        11111111"
     012
                LEGEND
                 ORTHO-PHENANTHROLINE
                0 BIPYRIDINE
                Q TRIPYRIOINE
                m BATHO PHENANTHROLINE
                B THIOCYANATE
                a THIOGLYCOUC ACID
                D SPECTROGRAPH
                D NOT SPECIFIED
                11111111111111111111111111111 M 11111111 M i M  1111111M11111
  4-6
                                         LABORATORY NUMBER

                                            Figure 4

-------
                                                              Statistical Analysis of Chemical Data
VIII SIGNIFICANCE
A  Definition

   Significance tests are tests by which we
   can determine the  relationship between,
   or the effect of,  a  number of factors.
                                                      Ana-
                                                      hst
                                                                M
                                                       A  10 +0  +0  +0 1
                                                       H  10 -1  +0  -Q 1
                                                       C  10+1  +0  +0 1
                                                                           Method
                                                                               2
10  +0  -2 -0 2
10  -1  -2 +0 I
10  +1  -2 +0 2
                                                                                        I'  C
                                                                                              W
                                                                                                   K
10  +0  +2 +0
10  -1  +2 -0 1
10  +1  +2 -0 1
  B  Two Significance Tests
     1  Analysis of variance (ANOVA)

        a  Definition:  ANOVA is a technique
           by which it is possible to isolate
           and estimate the variances contri-
           buting to the total variance of an
           experiment.
        b  An example of its use - 3 analysts
           each running 3 different methods
           of analysis without replication.

           X..  =  X  + C. +  M. +  E..
            i]          J      i     1J


Analyst
A
B
t:
Method sum
Method average
TABLE ;

1
10 1
8 9
11 1
30 1
10 03
3
Method
2
7 8
7 1
9 2
24 1
8 03

1
3
12 0
10 9
12 9
35 8
11 93

An
Sum
29 9
26 9
33 2
90 0
10 0

Jll>St
Aver-
9 97
8 97
11 07

     where    X-  = the result of any chemist
                   investigating any method

              X  = the true average
              C. = the chemist's  average error

              M. = the method average error

              E. = experimental  error
                                                                      TABLE  4
                                                                     ANOVA TABLE
                                                          Sourer of
                                                          variance

                                                       Between methods
                                                       Between amih ^tb
                                                       Error
                                                                          Degrees    Sum    Mean
                                                                         of freedom  squares   square
          22 82
          6 62
          0 10

          29 M
 11 41
  3 31
  0 025
                                                                                            4-7

-------
Statistical Analysis of Chemical Data
                                       TABLE  5*

                          CRITICAL VALUES OF F AT 5% LEVEL

f2
Denominator
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
fi Numerator

1
161
18.5
10. 1
7.71
6.61
5.99
5.59
5.32
5. 12
4.96
4.84
4.75
4.67
4.60
4.54

2
200
19.0
9.55
6.94
5.79
5. 14
4.74
4.46
4.26
4. 10
3.98
3.89
3.81
3.74
3.68

3
216
19.2
9.28
6.59
5.41
4.76
4.35
4.07
3.86
3.71
3.59
3.49
3.41
3.34
3.29

4
225
19.2
9. 12
6.39
5. 19
4.53
4. 12
3.84
3.63
3.48
3.36
3.26
3. 18
3. 11
3.06
J.
5
230
19.3
9.01
6.26
5.05
4.39
3.97
3.69
3.48
3.33
3.20
3. 11
3.03
2.96
2.90

6
234
19.3
8.94
6. 16
4.95
4.28
3.87
3.58
3.37
3.22
3.09
3.00
2.92
2.85
2.79

7
237
19.4
8.89
6.09
4.88
4.21
3.79
3.50
3.29
3. 14
3.01
2.91
2.83
2.76
2.71

8
239
19.4
8.85
6.04
4.82
4. 15
3.73
3.44
3.23
3.07
2.95
2.85
2.77
2.70
2.64

9
241
19.4
8.81
6.00
4.77
4. 10
3.68
3.39
3. 18
3.02
2.90
2.80
2.71
2.65
2.59

10
242
19.4
8.79
5.96
4.74
4.06
3.64
3.35
3. 14
2.98
2.85
2.75
2.67
2.60
2.54

12
244
19.4
8.74
5.91
4.68
4.00
3.57
3.28
3.07
2.91
2.79
2.69
2.60
2.53
2.48

16
17
18
19
20
21
22
23
24
25
30
40
60
120
o
4.49
4.45
4.41
4.38
4.35
4.32
4.30
4.28
4.26
4.24
4. 17
4.08
4.00
3.92
3.84
3.63
3.59
3.55
3.52
3.49
3.47
3.44
3.42
3.40
3. 39
3. 32
3.23
3. 15
3.07
3.00
3.24
3.20
3.16
3. 13
3.10
3.07
3.05
3.03
3.01
2.99
2.92
2.84
2.76
2.68
2.60
3.01
2.96
2.93
2. 90
2.87
2.84
2.2
2.80
2.78
2.76
2.69
2.61
2.53
2.45
2.37
2.85
2.81
2.77
2. 74
2.71
2.68
2.66
2.64
2.62
2.60
2.53
2.45
2.37
2.29
2.21
2.74
2.70
2.66
2. 63
2.60
2.57
2.55
2.53
2.51
2.49
2.42
2.34
2.25
2. 18
2. 10
2.66
2.61
2.58
2. 54
2.51
2.49
2.46
2.44
2.42
2.40
2.33
2.25
2. 17
2.09
2.01
2.59
2.55
2.51
2.48
2.45
2.42
2.40
2. 37
2.36
2.34
2.27
2. 18
2. 10
2.02
1.94
2.54
2.49
2.46
2.42
2.39
2.37
2.34
2.32
2.30
2.28
2.21
2. 12
2.04
1.96
1.88
2.49
2.45
2.41
2. 38
2.35
2. 32
2. 30
2.27
2.25
2.24
2. 16
2.08
1.99
1.91
1.83
2.42
2.38
2.34
2.31
2.28
2.25
2.23
2.20
2. 18
2. 16
2.09
2.00
1.92
1.83
1.75
 #This table is reproduced with the permission of Professor E. S.  Pearson from Merrington,  M.,
 Thompson,  C. M.   "Tables of percentage points of the inverted beta (F)  distribution, " Biometrika,
 Vol.  33 (1943),  p.  73.    (Ref. 2)

-------
                                                        Statistical Analysis of Chemical Data
                                        TABLP; 6*

                          CRITICAL VALUES OF  FAT 1% LEVEL
fi Numerator
f2
Denominator
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

1
4052
98.5
34. 1
21.2
16. 3
13.7
12.2
11.3
10.6
10.0
9.65
9. 33
9.07
8.86
8.68

2
5000
99.0
30.8
18.0
13.3
10.9
9. 55
8.65
8.02
7.56
7.21
6.93
6.70
6.51
6.36

3
5403
99.2
29. 5
16.7
12. 1
9.78
8.45
7. 59
6.99
6.55
6. 22
5.95
5.74
5.56
5.42

4
5625
99.2
28.7
16.0
11.4
9. 15
7.85
7.01
6.42
5.99
5.67
5.41
5.21
5.04
4.89
i
5
5764
99. 3
28.2
15.5
11.0
8.75
7.46
6.63
6.06
5.64
5. 32
5.06
4.86
4.70
4.56

6
5859
99.3
27.9
15.2
10.7
8.47
7. 19
6.37
5.80
5.39
5.07
4.82
4.62
4.46
4.32

7
5928
99.4
27.7
15.0
10.5
8.26
6.99
6. 18
5.61
5.20
4.89
4.64
4.44
4.28
4. 14

8
5982
99.4
27.5
14.8
10.3
8. 10
6.84
6.03
5.47
5.06
4.74
4.50
4.30
4. 14
4.00

9
6023
99.4
27.3
14.7
10.2
7.98
6.72
5.91
5.35
4.94
4.63
4. 39
4. 19
4.03
3.89

10
6056
99.4
27.2
14.5
10. 1
7.87
6.62
5.81
5.26
4.85
4.54
4.30
4. 10
3.94
3.80

12
6106
99.4
27. 1
14.4
9.89
7.72
6.47
5.67
5. 11
4.71
4.40
4. 16
3.96
3.80
3.67

16
17
18
19
20
21
22
23
24
25
30
40
60
120
OO
8.53
8.40
8.29
8. 19
8. 10
8.02
7.95
7.88
7.82
7.77
7.56
7.31
7.08
6.85
6.63
6.23
6. 11
6.01
5.93
5.85
5.78
5.72
5.66
5.61
5.57
5. 39
5. 18
4.98
4.79
4.61
5. 29
5. 19
5.09
5. 01
4.94
4. 87
4. 82
4.76
4. 72
4.68
4. 51
4. 31
4. 13
3.95
3.78
4.77
4.67
4. 58
4.50
4.43
4.37
4.31
4.26
4.22
4. 18
4.02
3.83
3.65
3.48
3.32
4.44
4.34
4.25
4. 17
4. 10
4.04
3.99
3.94
3.90
3.86
3.70
3.51
3. 34
3. 17
3.02
4.20
4. 10
4.01
3.94
3.87
3.81
3.76
3.71
3. 67
3.63
3.47
3.29
3. 12
2.96
2.80
4.03
3.93
3.84
3.77
3.70
3.64
3.59
3. 54
3.50
3.46
3. 30
3. 12
2.95
2.79
2.64
3.89
3.79
3.71
3.63
3.56
3.51
3.45
3.41
3.36
3.32
3. 17
2.99
2.82
2.66
2.51
3.78
3.68
3.60
3.52
3.46
3.40
3.35
3. 30
3.26
3.22
3.07
2.89
2.72
2.56
2.41
3.69
3.59
3.51
3.43
3.37
3.31
3.26
3.21
3. 17
3. 13
2.98
2.80
2.65
2.47
2.32
3.55
3.46
3.37
3.30
3.23
3. 17
3. 12
3.07
3. 03
2.99
2.84
2.66
2. 50
2.34
2. 18
* This table is reproduced with the permission of Professor E.S.  Pearson from Merrington, M.,
Thompson, C. M.  "Tables of percentage points of the inverted beta (F)  distribution, " Biometrika,
Vol. 33 (1943,1 p.  73.
                                                                                         4-9

-------
 Statistical Analysis of Chemical Data
    2  The t test

       a  Definition:  This is a special case
          of the ANOVA for use in the com-
          parison of 2 averages.

       b  It can be used in the following cases:

       Example 1 If two chemists analyze a
                  substance and we wish to
                  know if one is getting results
                  significantly lower than the
                  other.

       Example 2 If we wish to know whether,
                  in the above example, their
                  results can be  considered
                  as coming from the same
                  population.
IX  CONTROL CHART TECHNIQUE

 A Purpose: for testing of data readings to
    determine whether they show a change  in
    the conditions being measured, or whether
    they represent only chance fluctuations in
    the readings, one can apply the properties
    of the normal curve.  For a well-established
    set of criterion data,  a frequently used set
    of control limits is plus and minus three
    standard deviations.   That is, special
    attention is given to data readings which
    lie outside these limits in order to inves-
    tigate further whether the conditions
   under which the original data were taken
   have changed. Since the limits of three
   standard deviations on either side of the
   mean include 99.7 percent of the area
   under the normal curve, it is very unlikely
   that a reading outside these limits is  due
   to the conditions producing the criterion
   set of data.  The purpose of this technique
   is to separate the purely chance fluctuations
   from the other causes of variation.

B  Example: If a long series of observations
   of an environmental measurement yields
   a mean  of 50 and a standard deviation of
   10,  then we will wish to set up our  control
   limits as 50 plus and  minus thirty,  that is,
   plus and minus three  standard deviations,
   or from 20 to 80.  So for example,  a value
   of 80 will suggest  that the underlying condi-
   tions have changed, and that a large number
   of similar observations at this time would
   yield a  distribution of results with  a  mean
   different  larger   from 50.

C  Technique:

   This process of determining whether a
   value represents  a significant change  is
   closely  related to the use of control charts.
   Often in setting up control limits it is
   necessary to divide the available data into
   subgroups  and calculate the mean and
   standard deviations of each of these groups,
   making  careful note of the conditions pre-
   vailing  under each subgroup.
                                            random variations
                  +3
                   mean
                   -3
                        process out
                        of control,
                        investigation
                        needed
                                    Sequential data readings

                                  Figure 5.  CONTROL CHART
   4-10

-------
                                                          Statistical Analysis of Chemical Data
   In the collecting of data for setting up con-
   trol limits,  the time sequence can be im-
   portant,  for the data in a time series may
   reveal some non-random pattern of data.
   It is apparent  that as much information as
   possible  should be ascertained about the
   causes and conditions operating during the
   period of collecting data for the establish-
   ment of control limits.  Generally we will
   wish the  conditions during this period to
   be  normal, "  or as much in control as
   possible.

   In the situation where one takes readings
   of  some  environmental quantity, the
   appearance of  data beyond the control limits
   might suggest  the starting of a new grouping
   of data in order to ascertain further whether
   the  underlying environmental variable has
   changed.

D  Flexibility:

   It should  be kept in mind that the limits of
   plus and  minus 3 standard deviations are
   traditional rather than absolute.  They have
   been found through experience to be very
   useful in  many control situations,  but each
   experimenter must decide what limits will
   probably  work best for his purposes by
   determining what levels of probability he
   will need to  use for acceptance and rejection.
   More detailed discussions of the establish-
   ment of control limits can be found in
   references 1 and 4.
REFERENCES

1  Bennett,  C.A.,  and Franklin, N. L.
      Statistical Analysis in Chemistry
      and the Chemical Industry.  John
      Wiley & Sons, Inc.,  New York.  1954.

2  Bauer, E. L.  A Statistical Manual for
      Chemists. Academic Press,  New
      York.  1960.

3  Fraser, D.A.S.  Statistics: An Introduction.
      John Wiley & Sons, Inc., New York. 1960.

4  Dixon, W. J.,  and Massey, F. J.  Intro-
      duction to Statistical Analysis.   McGraw-
      Hill Book Co., Inc.,  New York.   1951.

5  ASTM Manual on Quality Control of Ma-
      terials.  American Society of Testing
      Materials,  Philadelphia.  January 1951.
                                                                                     4-11

-------
                       QUALITY CONTROL OF CHEMICAL ANALYSES

                                    Betty Ann Punghorst*
 I   INTRODUCTION

 In  any type of analytical work the analyst
 should ask the question "how well am I doing"
 or "am I getting the right results. "  It is not
 enough that these questions should be continu-
 ally asked, but they should also be continually
 answered.  The use of a systematic approach
 to  answering these questions is known as a
 quality control procedure.  It will be  the pur-
 pose of this discussion to point out some of
 these procedures which can be applied in the
 chemistry laboratory.

II   FUNDAMENTAL CONCEPTS

 Before presenting quality control procedures
 it is necessary to understand the concept of
 accuracy and the factors influencing it - known
 as  errors.

 A  Accuracy

    For results to be accurate (i.e.,  close to
    the true value) they must be both precise
    and unbiased.  The relationship among
    precision, bias and accuracy is shown in
    Figure 1.

    1  Precision

      The precision of results  is the degree
      of agreement between values obtained
      under substantially the same conditions.
      In other words,  it is a measure of the
      degree to which results "check. "
      Precision is influenced primarily  by
      indeterminate errors (see below).  It
      can be stated that if a reasonable pre-
      cision cannot be obtained by a method,
      accuracy can never be obtained.

    2  Bias

      Bias is introduced into a set  of  results
      obtained  under substantially the same
      conditions when the sample mean
      (average of the results) deviates
      considerably from the true mean. Bias
      is introduced primarily by determinate
      errors (see below) which introduce a
      constant error into the data.  For ex-
      ample, an analyst obtains precise re-
      sults in the determination of iron in
      water (1,  10 phenanthroline).  However,
      his results are far from the  true value
      because he introduced bias by reading
      the absorbance of the solutions at 450
      mp. instead of 510 m|j. (the maximum
      absorbance).

B  Error

   The variation pattern of a series of results
   of a chemical analysis has two main com-
   ponents  - that produced by "assignable
   causes" and that produced by "chance
   causes."

   1   Determinate error

      Determinate errors are those which can
      be given an "assignable cause. "  There
      are several kinds of determinate errors.

      a  Instrumental errors

        An error of this type could be due to
        a buret  which is incorrectly calibrated.

      b  Method  errors

        This is  the most common type of
        error arising due to the presence  of
        interferences in the sample.  An error
        of this type also occurs when  a method
        is not applicable to the material being
        analyzed.

      c  Personal errors

        These errors are attributable to
        individual mistakes made by the
        analyst.
-Chemist, DWS&PC Training Activities SEC.  Reviewed December 1965.
CH.8.8.64                                                                             5-1

-------
Quality Control of Chemical Analyses
             Inaccurate
       Imprecise and Biased
             Inaccurate
        Precise, but  Biased
              Inaccurate
      Unbiased,  but  Imprecise
              Ace urate
       Precise  and  Unbiased

  PRECISION BIAS AND ACCURACY
              FIGURE!
    2  Indeterminate error (random error)

       Even when all determinate errors  are
       eliminated, every replicate analysis
       will not give the exact same value.  In-
       determinate error, then,  is that which
       is attributable to "chance causes. "
       Indeterminate errors, or perhaps the
       better nomenclature would be  indetermi-
       nate variations in results, are something
       with which we have to live.  Fortunately,
       these indeterminate variations conform
       to the laws of statistical distributions.
       A measure of their magnitude is obtained
       by the standard deviation(s).
Ill  QUALITY CONTROL PROCEDURES

 It is the purpose of a quality control program
 to detect all determinate errors in analyses
 so that subsequent steps can be taken to
 eliminate them. Consequently  it is first
 necessary to obtain an estimate of the inde-
 terminate error by calculating  the standard
 deviation  of the analysis.

 A  Calculation of Standard Deviation

    Formula (1) can be found in  any statistics
    book and is convenient if one wishes to take
    the time to run  many analyses on the same
    sample.  However,  it is more practical
    for the chemist to use data accumulated
    over a period of time  on different samples.
    In this situation formulas (2) and (3) are
    applied.
                                                 fj-**x
                                                 i  r Replicate results on the same sample:
                                                     (1)  s
           X.  =
             1

           X
                      (X. - X)'

                       n -~1
value of single result

average of results on
same sample

number of results
  5-2

-------
                                                    Quality Control of Chemical Analyses
 Example: Table  1 contains a set of 5-day
          BOD results obtained on a
          synthetic  sample containing
          150 mg/1  of glucose and 150 mg/1
          glutamic acid.  (Note:  A 1%
          dilution was  used in the actual
          test.)  Calculate the standard
          deviation  of these results.
       X =  192 mg/1
       n =  36.0
(X.-X)  =  58,200
                         Example:  Table 3 contains a set of %
                                    nitrogen results obtained on
                                    unknown organic compounds.

                                    Calculate the standard deviation.
                                    z(x. -XT  =
                                                                  n - k  =
                                                                           .2401
          -
                :, 200
                35
       s  =  41 mg/1


2  Duplicate results on different samples


   (2)  s  =!/" W    (See reference 4,
                        page 654)
                2k
       d  =  difference between duplicates

       k  =  number of samples
Example: Table 2 contains a set of
          phosphate results obtained on
          aqueous samples in the range
          100 - 200 mg/1.  Calculate the
          standard deviation of these
          results.
3  Duplicate and triplicate results on
   different samples
   (3)
                  - k
(See reference 5,
 page 73)
                                                                         =  . 104%
                      B Establishment of Rating System

                         Now that an estimate of indeterminate
                         error has been made, it becomes necessary
                         to submit periodic check samples for
                         analysis in order to estimate determinate
                         error.  In the laboratory where analysts
                         are performing routine analyses,  it is
                         then possible to establish a rating system
                         to check the analyst (personal error).  One
                         laboratory (see reference 6) has  established
                         such a system in the following way:

                         1  Three percent of all analyses  done
                            are check samples with known values.

                         2  Penalties  are assigned to analysts
                            according to the following norms:

                            a  One penalty for any value obtained
                               on a check sample which is between
                               0. 8 and 1. 6 of one standard
                               deviation.

                            b  Two penalties for any value obtained
                               on a check sample which is between
                               1.6 and 2.4 s.

                            c  Six penalties  for any value  obtained
                               on a check sample which is between
                               2.4 and 3.2 s.

                            d  Twenty-four penalties for any value
                               obtained on a check sample which is
                               outside 3. 2 s.
                                                                                    5-3

-------
Quality Control of Chemical Analyses
                                        Table 1

      SAMPLE:           150 mg/1 glucose + 150 mg /I glutamic acid (1% dilution)
      DETERMINATION:  5-day Biochemical Oxygen Demand
X.
1
100 mg/1
117
125
132
142
147
153
160
165
165
167
173
178
189
190
196
196
197
X. - X
i
-92 mg/1
-75
-67
-60
-50
-45
-39
-32
-27
-27
-25
-19
-14
- 3
- 2
4
4
5
(X. -X)2
i
8464 (mg/1)2
5625
4489
3600
2500
2025
1521
1024
729
729
625
361
196
9
4
16
16
25
X
i
198 mg/1
199
200
200
204
210
211
212
215
223
224
227
229
238
247
250
259
274
X. - X
i
6 mg/1
7
8
8
12
18
19
20
23
31
32
35
37
46
55
58
67
82
(X. - X)2
i
36 (mg/1)2
49
64
64
144
326
361
400
529
961
1024
1225
1369
2116
3025
3344
4489
6724
       Data taken from Water, Oxygen Demand Report (July,  1960),  Analytical Reference
       Service, Training Program,  R. A.T.  Sanitary Engineering Center, Cincinnati, Ohio.
  5-4

-------
                                                       Quality Control of  Chemical Analyses
    SAMPLE:
    DETERMINATE
Aqueous        ae            RANOE: 10-200 m*'1
Phosphate (Lucerna, Conde, and Prat Method)
Sample
A

B

C

D

E

F

G

H

I

J

K

Mg/1






!
1.
1!
1!
1!
1'
1!
1
1
1
1
1
1
1
1
1
PO^
B
4
2
3
5
8
6
8
7
a
0
6
5
6
7
6
2
1
7
8
6
7
d
6

0

3

0

1

4

1

1

1

1

1

d3
36

0

9

0

1

16

1

1

1

1

1

Sample
L

M

N

0

P

Q

R

S

T

U

V

Mg/1 P04"3
170
175
118
118
181
161
181
181
168
169
168
170
151
151
161
160
165
165
143
146
130
130
d
5

2

0

0

1

2

0

1

0

3

Q

d2
25

4

0

0

i

4

0

1

0

9

0

     Data obtained fro
                    n Frank Schickner, Proctor and Oamble Company.
                                   Table 3*
SAMPLE: Unknown Organic Compounds
DETERMINATION- % Nitrogen (Kjeldahl)
Sample
A

B

C

D


E


F



G

H


I

%N
16.48
16.46
16.50
16.49
16.72
18. 57
17.52
17.80
17.63
16.31
16.30

16.40
16.31
16.35

17.56
17.54
14.96
14.66

19. 15
18.89
X
16.47

16.50

16.65

17.58


16. 31


16.35



17.55

14.81


19.02

V*
.01
.01
0
.01
.07
.08
.06
.02
.05
0
.01

.05
.04
0

.01
.01
. 15
. 15

. 13
. 13
(V*,2
.0001
.0001
0
.0001
.0049
.0064
.0036
.0004
.0025
0
.0001

.0025
.0016
0

.0001
.0001
.0225
.0225

.0169
.0169
Sample
J

K

L

M


N


o


P

Q


R


%N
13.93
13.56
10. 34
10. 19
17. 16
17. 13
15.01
15.05

12.44
12.70
12.73
14.37
14.36

11.85
11.85
14.79
14.70
14.70
17. 19
17. 14

RANGE
* i
13.75

10.27

17. 15

15.03


12.62


14.37


11.85

14.73


17. 17


: 10%-20%
-Jf
18
19
07
08
01
02
02
02

. 18
08
11
0
01

0
0
.06
.03
.03
.02
.03

2
.0324
.0361
.0049
.0064
.0001
.0004
.0004
.0004

.0324
.0064
.0121
0
.0001

0
0
.0036
.0009
.0009
.0004
.0009

*Data obtained from Frank Schickner, Proctor and Gamble Company.
                                                                                       5-5

-------
Quality Control of Chemical Analyses
   3  Analysts are then rated according to
      the following formula:
      (4)  Rating  = 100 -
                            D
      p =  number of penalties assigned to
           analyst
      D  =  number of determinations done by
           analyst
The expected rating for an analyst
has been set at 89.4.  In other words,
an analyst is expected to receive a
certain number of penalties due to the
inherent  indeterminate error in
analyses.  Table  4 shows an example
of the rating system.

Penalties are divided between analyst
if more than one  analyst is responsible
for a determination.
                                          Table 4*

                     ACCURACY     BIWEEKLY   June 22 - July 3, 1964
                       .   ,       Number of     _   ....     _ ,.
                       Analyst   . .     .          Penalities   Rating
                           J    determinations
A
B
C
D
E
F
G
H
I
J
K
L
M
N
0
P
Q
R
S
T
U
Total
.00
.00
.00
1.00
2.00
.00
.00
1.00
7.50
3.00
.00
1.00
.00
.00
.00
.00
2.00
.00
.00
1.50
5.00
24.00
.00
.00
.00
.00
.00
.00
.00
.00
1.50
1.00
.00
1.00
.00
.00
.00
.00
.00
.00
.00
.50
.00
4.00
.00
.00
.00
100.00
100.00
.00
.00
100.00
96.60
94.33
.00
83.00
.00
.00
.00
.00
100.00
.00
.00
94.33
100.00
97. 16
                       Data obtained from Frank Schickner, Procter
                       and Gamble Company.
  5-6

-------
                                                       Quality Control of Chemical Analyses
    5  If a value for a check sample falls out-
      side 2.4 standard deviations,  an inves-
      tigation is made to  see if the variation
      is due to some determinate error.

 C  Other Quality Control  Procedures

    1  Internal standards can be used to check
      method errors.

    2  Analysis of a sample for a desired con-
      stituent by two or more methods that are
      entirely different in principle (gravimetric
      and volumetric) may aid in the estimation
      of error.

IV  SUMMARY

 The elementary concepts of accuracy and
 error are presented.  Quality control pro-
 cedures for the detection of determinate
 errors  are discussed.

 REFERENCES

 1   Allan,  Douglas H.  Statistical Quality Con-
    trol. Reinhold Publishing Corporation.
    New York. 1959.
2  American Society for Testing Materials.
      ASTM Manual on Quality Control of
      Materials.  Special Technical
      Publication 15-C. 1951.

3  Bauer, E.L.  A Statistical Manual for
      Chemists.  Academic Press.  New
      York.  1960.

4  Bennett,  Carl A.,  and Franklin, Norman
      L.  Statistical Analysis in Chemistry
      and the Chemical Industry.  John Wiley
      & Sons, Inc. New York. 1954.

5  Mickley,  Harold S., Sherwood, Thomas
      K., and Reed,  Charles E.  Applied
      Mathematics in Chemical Engineering.
      McGraw-Hill Book Company.  New York.
      1957.

6  Schickner, Frank A. Personal Communi-
      cation. The Proctor & Gamble
      Company,  Miami Valley Laboratories,
      Research and Development Department.
      P.O.  Box  39175. Cincinnati, Ohio
      45239.
                                                                                     5-7

-------
                   CRITERIA FOR SELECTION OF ANALYTICAL METHODS

                                        J.  W. Mandia*
 I   THE PROBLEM

 The multiple use concept of water resources
 necessitates selection of analytical methods
 not presently found in Standard Methods for
 Examination of Water and Waste-water,
 llth edition,  1960.  For example, for the
 analysis of organic pollutants, in particular
 pesticides, there are no standard methods
 in existence.

 What guidelines can we  use to investigate a
 pollutional problem in a body of water,  where
 we are forced to seek chemical methods out-
 side of traditional standard methods?
II   GUIDES FOR SELECTION OF AN
    ANALYTICAL METHOD
   C  Analytical Skill Required

      1  Analytical instruments

         a  Spectrophotometer

         b  Infrared

         c  Gas chromatography


      2  Competence of personnel

         a  Operate instrument  required for
           analysis of pollutant.

         b  Interpret results of  analysis;
           sensitivity, precision,  accuracy,
           range,  etc.
 A  Legality of Method

    1   Method must be officially recognized
       by some chemical professional
       organization.

    2   Status of method must be specified.


 B  Chemical Entity Involved

    1   Concentration of chemical pollutant
       estimated in order to select analytical
       range of procedure.

       a  Macrochemical procedures:
         volumetric, gravimetric

       b  Microchemical procedures:
         spectrophotometric, colorimetric


    2   Method should be pollution  oriented.

       a  Clean-up procedures

       b  Significant interferences
 III   OFFICIAL ORGANIZATIONS AND
      MANUALS OF METHODS FOR CHEMICAL
      ANALYSES
  .1
--"/A  The Associations of American Public
      Health, American Waterworks and the
      Water Pollution Control Federation
      jointly publish the Standard Methods for
      the Examination of Water and Wastewater.

      1  Status of methods in the Manual
        Standard Methods

        a  Methods designated "Standard" -
           these methods have been extensively
           studied and accepted as applicable
           within the limits of sensitivity, pre-
           cision,  and accuracy recorded.

        b  Methods designated "tentative" -
           methods which are still under
           investigation and have not yet been
           fully evaluated.

      2  Updating Standard Methods

        a  The job of checking a promising
           method is assigned to  one or more
           laboratories comprising a subcommittee.
*Chemist, DWS&PC Training Activities, SEC.  Reviewed December  1965.
CH. MET. 22. 11.64                                                                       6-1

-------
Criteria for Selection of Analytical Methods
      b If preliminary findings are encourag-
        ing, further checking is made in
        additional laboratories.

      c If the method is generally agreed to
V^      be  applicable, it is admitted into
o'       Standard Methods on a tentative basis.


B> The American Society for Testing Materials
   was founded in 1898 as a national tech-
   nical society.  It  is composed of some 87
   main technical committees with almost
   2000 subcommittees.

   1  Committee D-19 publishes a manual on
      Industrial "Water and Industrial
      Wastewater.

      a The manual lists 21 chemical para-
        meters and concentrations as water
        quality tolerances which if exceeded,
        may be deleterious to  the industry's
        product or operation.

      b Quality is defined as a relative term
        that depends upon desired use.

      c Pollution is defined as that condition
        of water in  which the concentration of
        contaminants interferes with a down-
        stream use of the water.

   2  Status of methods in ASTM Manual

      a Referee methods

        These methods  are employed when
        extremely accurate analyses have
        to be performed due to narrow
        tolerance ranges.  Special considera-
        tion is given for the elimination of
        interferences.

      b Nonreferee methods

        These methods  are employed when
        extreme accuracy is not required
        and usually when interferences are
        at a minimum.  These methods are
        usually easier and more rapid than
        the referee methods.
'C" The U.S.  Geological Survey - Water
   Quality Branch

   The Geological Survey has the responsi-
   bility for  measuring and evaluating water
   moving through that portion of the hydro-
   logic  cycle between the time the water
   from  the atmosphere reaches the earth's
   surface and the time it is returned to the
   atmosphere.

   The Water Quality  Branch of the Water
   Resource Division  determines and
   approves  the chemical and physical
   characteristics of the Nation's water
   resources.  The  branch publishes the
   manual "Collection and Analyses of Water
   Samples.  "

   1  The manual is prepared under the
      immediate supervision of the Chief of
      the Chemical Quality Section of  the
      Water  Quality Branch.

   2  Analytical  Methods are based largely
      on experience of survey chemists.

   3  The manual has an extensive and
      detailed description of water sampling
      procedures for both surface and
      ground water.

   4  The manual has excellent recommenda-
      tions for preservation of samples for
      analysis of various chemical constitutents.

   5  The procedures listed first in each
      group  of methods is generally preferred
      because of its applicability to most
     ^water  samples.

 D -The Association  of Official Agricultural
   Chemists (AOAC)

   This organization is not concerned
   particularly with methods of water
   analyses, but it is  vitally interested in
   analytical methodology which may be
   employed in water analyses.
6-2

-------
                                                   Criteria for Selection of Analytical Methods
 *  1  Function of AOAC

       AOAC is the professional organization
       of state and federal scientists devoted
       to developing,  testing and approving
       methods for analysis of fertilizers,
       feeds,  pesticides,  foods, drugs,
       cosmetics and other materials related
       to agricultural pursuits.

       a Many food industries as well as the
         Public Health Service are members
         of the organization.

       b AOAC was founded in 1884 and was
         organized by state  and federal
         chemists.
    2  Status of methods

       AOAC methods are designated as
       "official, " "first action" and
       "procedures."

       a  Official methods are those endorsed
         and recommended by the organization.

       b  "First action" are those methods
         which after an initial collaborative
         study, show a suitable degree of
         accuracy and reproducibility.  By
         labeling a method "first action" an
         opportunity is provided for those
         interested in the method to study  it
         further before its final adoption as
         "official.  "

       c  "Procedures" are well established
         techniques,  such as sampling and
         preparation of sample, which are
  (      difficult to study collaboratively.

''\
 E  Handbook for the U. S. Salinity Laboratory
    Staff

    The organization is an agricultural research
    service, and is a  collaborative effort
    among eleven Agricultural Experiment
    Stations in western states.

    1   Method of analyses

       a  Irrigation water analysis is the
         major topic of the handbook.
      b  Special parameters such as residual
         sodium carbonate,  sodium absorp-
         tion ratio and soluble sodium per-
         centage are explained.


    2  Pertinent analyses

      a  Total dissolved solids

      b  Boron

      c  Alkalinity and hardness
IV  THE JOINT COMMITTEE ON UNIFORMITY
    OF METHODS OF WATER EXAMINATION

 A  Organization of JCUMWE

    1  ASTM Committee D-19

    2  Standard Methods Committee of APHA,
      AWWA, and WPCF

    3  U.S.  Geological Survey Water Quality
      Branch


 B  Functions of JCUMWE

    1  JCUMWE reviews the methods of water
      examination published by member
      organizations for the purpose of obtain-
      ing uniformity in sampling, testing,
      reporting test data,  terminology and
      in application.

    2  JCUMWE provides a mechanism for the
      exchange of information on these  matters
      by member organizations.


 REFERENCES

 1   Manual on Industrial Water and Industrial
      Wastewa'ter.  ASTM.  2nd Ed.  1962.

 2   Standard Methods for the Examination of
      Water and Wastewater.  llth Ed.   1960.

 3   Methods for Collection and Analysis  of
      Water Samples.  Geological  Survey.
      Water - Supply Paper 1454.  1960.

 4   U.S.  Salinity Laboratory Agricultural
      Handbook.   No.  60.   1954.
                                                                                        6-3

-------
                              DISSOLVED OXYGEN DETERMINATION

                                        James W.  Mandia*
 I   APPLICATIONS

 A  Quality of Surface Waters

    In determining the sanitary condition of
    surface waters, the DO is often the most
    important single criteria.  The effect of
    oxidizable wastes on streams, the evalu-
    ation of water condition for fish and other
    organisms,  and the  progress of self-
    purification, all can be measured by DO
    determinations.

 B  Biochemical Oxygen Demand Tests

    OxidJZah|e Wpgtog ar-o gonci-^lly

 C Waste Treatment Control

   Aerobic treatment  systems are most
   efficient when dissolved oxygen levels are
   carefully maintained.  Frequent measure-
   ment of DO is necessary for adequate
   control.  The efficiency of this type of
   treatment may be measured by changes
   in
II  ANALYTICAL METHODS

 A Chemical

   The Winkler method, developed in 1888,
   is the basis for routine chemical determin-
   ation of DO.   The presence of certain
   commonly occurring interferences require
   modification of the original method.

   In recent years,  other chemical methods
   using various reduced dyes have been
   proposed.  None of these have found wide
   acceptance since they are more difficult
   and less precise than the modified Winkler
   method.
   1  Winkler method

      a  Reactions

        The basic procedure involves the
        oxidation of manganous hydroxide
        (Mn++) by the oxygen in the water:
(1)
(2)
(5)
      MnSO4 + 2KOH ~~ Mn(OH)2 + K2SO4
      2Mn(OH)2 + O2  2MnO(OH)2
        The manganous hydroxide is a white
        flocculant precipitate which changes
        to light brown when oxidized.  Since
        the reaction with the oxygen  must
        occur on the surface of the floe
        particles, physical mixing at this
        point is important.

        When manganic hydroxide is acidified,
        manganic sulfate is formed:
(3)   |MnO(OH)2 + 2H2SO4  Mn(SO4)2 + 3H2O
        In the presence of iodide, the man-
        ganic salt acts as an oxidizing agent,
        releasing free iodine:
                                                  (4)   JMn(SO4)2 + 2KI-- MnSO4 + K2SO4 + I2
        The iodine, which is stoichiometri-
        cally equivalent to the DO of the
        sample,  is titrated with thiosulfate:
          2Na2S2O3  2Na2S4O6
        For convenience,  the alkali in
        equation 1 and the iodide in equation
        4 are combined into a single alkaline-
        iodide reagent.

     b  Interferences

        The whole system of reactions
        shown above is stoichiometric and
        interdependent:
 *Chemist, DWSPC Training Activities,  SEC.

 CH. O. do. 18b. 12.65
                                      7-1

-------
Dissolved Oxygen Determination
      THIO = I2 = Mn(SO4)2 = MnO(OH)2 = O2
        The dissolved oxygen present in the
        sample initiates a series of oxidation
        reactions.  All  reagents, except the
        final titrant, are in excess. The
        presence of interfering materials
        may seriously affect the accuracy
        of the  determination.  Oxidizing
        agents other than oxygen may produce
        similar reactions,  yielding high
        values (positive interference).  Con-
        versely,  reducing agents may inhibit
        the oxidation of the manganous hydrox-
        ide or reduce the free iodine,  produ-
        cing low results (negative interfer-
        ence).

        There are three significant interfering
        substances often found in natural
        waters.   These are nitrite  ion, fer-
        rous iron, and organic matter.  In
        addition to these,  polluted waters
        and  sewage may contain surfactant
        compounds (from household deter-
        gents) which partially obscure the
        endpoint of the thiosulfate titration.

        Nitrite

        Nitrite ion is formed by the biological
        degradation of proteinaceous  mater-
        ials.  It is therefore present  in nearly
        all natural waters.  In the Winkler
        reaction, nitrite ion becomes nitrous
        acid,  releasing iodine:
         2 HNO2 + 2HI  12 + 4H2O + N2O2

                                    I
         4 HNO2   O2 + 2H2O + 2N2O2
         The continual release of iodine pro-
         duces very high apparent DO values.
         When nitrite ion is present at a    !
         concentration of only 5 mg/1,  the   f
         positive DO error may amount to
         three times the true DO.

         Because nitrite is so common in DO
         sarnples71he Winkler procedure is
         customarily modified to remove this
         interference.  The Alsterberg
nxodiiea4ion,  incorporating sodium
azide in the, alkaline-iodide, reagent,
is very effective,  requires-no extra
manipulation,  and is therefore- the.. -
method of choice for all samples,
unless additional modification is
required. The azide converts the
nitrite ion to gaseous nitrogen com-
pounds which are evolved from the
sample:
(1)
NaN
                          HN3
(2)  HN3 + HNO2 N2 + N2O + H2O
Ferrous Iron

In many areas, the soils and rock
formations contain appreciable
quantities of ferrous  iron.  When the
formations are leached by ground and
surface waters, ferrous iron concen-
tration  in the receiving streams may
reach 100 mg/1.  The iron, being in
the reduced state (Fe++) may react
with the DO in the water,  causing
depletion.  When the  sample is
analyzed by the Winkler method, the
ferrous iron reduces the free iodine,
causing additional negative interfer-
ence.  Studies have shown that 1 ppm
Fe++ causes an error of -0. 14 mg/1
in the apparent DO.

When ferrous
   ^sample, the Rideal-Stewart
modification musFbe used.  The pro-
cedure consists of a preliminary
oxidation of the iron with acid per-
manganate,  removal of the excess
permanganate with oxalate, followed
by the Winkler (azide) procedure.
Ferric iron, often present in the
original  sample and produced in the
R-S oxidation,  is removed from
reaction by  complexing with potas-
sium  fluoride.

Organic  Matter

To support living organisms in water,
organic matter must be present.  In
clean, unpolluted waters,  the organic
  7-2

-------
                                                               Dissolved Oxygen Determination
 material is well stabilized and in
 relatively low concentration.
 Domestic sewage and many industrial
 wastes, however,  contain large
 amounts of organic matter.  In the
 Winkler procedure,  interference
 occurs at high pH,  and also after
 acidification.  Some organic com-
 pounds hydrolyze in the presence of
 alkali,  with accompanying oxygen
 demand.  At the pH  used  in the first
 stage of the Winkler procedure,  many
 organic materials will remove part
 of the  DO by hydrolysis.  Later,
 when acidification releases iodine,
 organic materials may exhibit an
 "iodine demand" much like the fa-
 miliar chlorine demand.  Both of
 the interferences produce a DO that
 is lower than the true value.  When
 1000 ppm of an organic compound
 was added to a tap water  sample,
 the determined DO value  was  reduced/
\3 mg/1.

 Since both the hydrolysis and  the
 iodine demand are time-dependent,
 i. e. ,  do not occur instantaneously,
 the effect of the interferences can
 be reduced by shortening the  period
 at which the organic matter is held
 at high pH,  and the time in which
 free iodine is present.  The Theri-
 ault_ _m odif ic a t ion^qr__Shor t, .WjnMe,,r
 method, consists of the Alsterberg
 procedure,  accomplished as rapidly
 as possible.  Thus the customary
 settling is eliminated and the  solution
 is titrated immediately upon acidi-
 fication.  Speed of manipulation is
 important, since the shorter  the
 elapsed time, the  less the interfer-
 ence.  Even with rapid execution of
 the procedure, some hydrolysis  and
i iodine demand occurs,  so that at
jjbest the error is reduced rather than
! eliminated.
Ill  SAMPLING FOR CHEMICAL DETERMINA-
    TION OF DISSOLVED OXYGEN

 A Effect of Light

    1  Algae react to the presence or absence
       of light.
                                                      2  Sunlight is used in production of oxygen
                                                         by algae.

                                                      3  Darkness creates a net demand for
                                                         oxygen by algae.

                                                      4  Sunlight might bring about changes in
                                                         test procedures by photochemical
                                                         reaction.

                                                   B  Effect of Temperature

                                                      1  Temperature is recognized as a factor
                                                         affecting the dissolved oxygen of a
                                                         sample.

                                                      2  Biological action is greatly reduced
                                                         at lower temperature.

                                                      3  Icing preserves samples.

                                                   C  Chemical Treatment of Sample

                                                      1  lodined, acid-azide fixed and untreated
                                                         samples all  showed the most  consistent
                                                         results when samples had been  iced,
                                                         and  stored not more than 6 hours on
                                                         ice under dark conditions.

                                                      2  Icing of untreated samples merits
                                                         consideration, provided that samples
                                                         are  kept in the dark and  that there is
                                                         minimal delay between sample col-
                                                         lection and laboratory testing.
IV  ELECTROCHEMICAL METHODS

 A Theoretical Concepts

    The polarographic method of analysis has
    been employed in the determination of DO,
    with good success.   Modifications of the
    basic instrument are commercially avail-
    able.  In the case of certain industrial
    wastes, the polarographic method yields
    better precision than standard wet chemi-
    cal procedures.

    The polarographic determination of DO is
    based on the reduction of oxygen at the
    small polarizable electrode.  Oxygen mole-
    cules are reduced in two steps, as shown
    in the following equations:
                                                                                          7-3

-------
Dissolved Oxygen Determination
   (1)

   (2)
O2 + 2H2O + 2e" " H2O2 + 2OlF[
        2e"
   These reactions produce a polarogram
   having two distinct plateaus.  Measure-
   ments of the diffusion current on the first
   plateau,  involving the first reaction,  are
   generally made at 0. 3 - 0. 6 Volts vs.SCE.
   Since a prominent maxima occurs in this
   range,  maxima suppression, by the addi-
   tion of surface active organics or strong
   electrolyte,  is necessary.

   In Figure 1 the standardization curves for
   the polarograph using the Winkler pro-
   cedure are shown.  The  applied voltage
   is set at  0. 4 Volts vs. SCE  which is about
   half of the distance between the 0. 3 and
   0.6  Volts plateaus and known concentrations
   of dissolved oxygen are recorded in milli-
   meters of curve height.
B  Theory of Polarographic Method

   1  Electrode assembly - Dropping
      Mercury Electrode (DME)

      Because  of the possibility of changes
      in DO content with siphoning,  the
      electrode assembly is generally designed
      to fit into the sample bottle or reaction
      vessel,  rather than into a standard
      polarographic cell. The saturated
      calomel electrode,  (SCE) currently
      used as a reference electrode, must
      be small to permit entry into the sample
      bottle.  Since changes in temperature
      would affect the DO concentration, the
      bottle is  generally not placed in a
      thermostated bath,  but instead a small
      thermometer is included in the assembly
      and the actual temperature noted
      (Figure 2).
   Traditionally,  polarographic techniques
   have utilized the dropping mercury
   electrode; most analyses are still per-
   formed with this system.  However, in
   the  determination  of DO, particularly
   in long term studies such as BOD rate
   curves and continuous  recording,  large
   quantities of mercury  are required.
   In addition,  the solubility of  mercury
   in water,  though very small,  can con-
   tribute significant toxicity where sensi-
   tive organisms are present.

   The DME is not reliable for  use in
   flowing streams due to the  distortion
   of the  drops by wave action.

2  Noble metal electrodes

   Because  of the difficulties mentioned
   above, the substitution of solid metal
   electrodes for the DME has  been
   studied  repeatedly.  In many analyses,
   the  rotating platinum electrode  has
   certain  advantages.  In amperometric
   titrations especially, it  has performed
   very well.  Current values are much
   higher with the solid electrodes, giving
   greater  sensitivity.  For determination
   of DO, however,  the results have been
   disappointing.  During electrolysis the
   adsorption of decomposition products
   onto the platinum surface alters  the
   electrode behavior  to such an extent
   that accurate current measurements
   are impossible.   Various systems  for
   intermittent brushing of the electrode
   or  electrical removal  of the "poisoning"
   substances have not been satisfactory.

3  Platinum DO electrode

   A new electrode system, suggested by
   Clark and  modified by Dr. John Kan-
   wisher at the Woods Hole Oceanographic
   Institute, offers possibilities for  reliable
   DO measurements with a solid platinum
   electrode.  The fundamental reaction is
   similar to that involving the DME or the
   rotating  electrode, but several signifi-
   cant changes in design are incorporated.
   A platinum disc,  1-3 cm.  in diameter,
   constitutes the cathode surface.   The
   anode is a silver-silver oxide reference
   electrode with a mixture of N/2 KC1 and
7-4

-------
                                                          Dissolved Oxygen Determination  	
      N/2 KOH,  forming the salt bridge.  The
      surface of  the platinum is  covered by a
      thin film of polyethylene, which is held
      in place by a retaining ring.  A  thin layer
      of the electrolyte is trapped between the
      platinum and the plastic film (Figure 3).

      In use the polyethylene film is  imper-
      meable  to ions but  is relatively per-
      meable to gaseous oxygen.  Thus the
      electrode poisoning encountered with
      bare metallic electrodes is avoided.
      Since  ions  do not reach the platinum
      surface,  the electrode characteristics
      remain constant.   Current  from this
      electrode can be fed to an indicating
      microammeter for  immediate reading
      or to a suitable recorder for  contin-
      uous use.

      Two factors require careful control:
      (1) the electrode is very sensitive to
      changes in  temperature,  the current
      increasing  about 5% for each 1 increase
      in temperature.  The use of a thermis-
      tor in the circuit to compensate for
      temperature effects is being  studied.
      (2)  Since the electrode is not rotating,
      the sample must flow across  the elec-
      trode face.   Increasing the  sample
      stirring from quiescence to vigorous
      stirring results in a 30% change in
      current.

      The behavior characteristics and de-
      sign factors of this  new electrode are
      being studied at the Sanitary Engineer-
      ing Center.  Field tests are in progress
      to determine  the applicability to auto-
      matic  recording of DO changes.

C  Applications of the Polar ographic Method

   The polarographic method has been
   studied extensively in an attempt to over-
   come the limitations of the Winkler
   method.  A variety of industrial  waste
   samples were  investigated and good re-
   sults were obtained in  the presence of
   sewage, heavy metals, dairy and laundry
   wastes.  The method has been applied  to
   the BOD determination as well as reaera-
   tion studies.
V
The polyethylene-covered electrode offers
promise for both laboratory and field
determinations.  The problems of tempera-
ture control and water movement are
currently being studied in several
laboratories.

EXAMPLES OF DISSOLVED OXYGEN
PROBES
A  The Beckman Oxygen Sensor

   The Beckman oxygen sensor system con-
   sists of a gold cathode, a silver anode, a
   temperature compensating thermistor,  a
   source of polarizing voltage, an amplifier
   and a means of read-out (Figure 4).

    A platinum cathode and silver anode
    oxygen sensor was an earlier Beckman
    model (Figure 5).

    1 The anode and cathode are electrically
      connected by a conductive gel of cellu-
      lose base potassium chloride,  and both
      elements  are  separated from the sam-
      ple to be measured by a gas permeable
      membrane 
-------
Dissolved Oxygen Determination
                                                                                     7-6

-------
                                                         Dissolved Oxygen Determination
           SCE*-
                        Thermometer
                  -DME
Figure 2.  ELECTRODE ASSEMBLY FOR
          DO DETERMINATION

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                              Figure 4.  THE BECKMAN OXYGEN
                                            SENSOR
                                                               OXYGEN ELECTRODE
      L-Platinum Disk
                             Silver Ring
Electrolyte Layer
     Figure 3.  DISSOLVED OXYGEN
              ELECTRODE
                                                         GLASS
                                                                             AMPLIFIER
                                                                                 mOlECTWI CASi
                                                       ELECTROLYTE
                                                                     MEMMANE

                                                                    Figure 5
                                                                                          7-7

-------
Dissolved Oxygen Determination
   7  For convenience, the direct use of
      parts per million in dissolved oxygen
      measurements has  often been employed.
      Some workers regard percent saturation
      as the more meaningful consideration.

   8   In order to read the correct oxygen con-
      centration accurately and continuously,
      a fresh representative sample must be
      maintained at the tip of the oxygen sen-
      sor at all times during measurement.
      Rate  of oxygen diffusion is  so slow that
      it is unable to replenish even the minute
      quantity consumed by the sensor.

   9   Calibrating the oxygen sensor for ppm
      dissolved oxygen measurements may be
      accomplished by one of several methods:

      a   Grab sample method  - correlation of
         oxygen analyzer  with Winkler method.

      b   Saturation technique - this involves
         bubbling of air or oxygen through
         water sample until saturation is
         reached and then setting the  oxygen
         analyzed to read either ppm oxygen
         or 100% saturation.

      c   Air calibration - since the partial
         pressure of oxygen (160 mm) is the
         same in air as it is in a 100% air
         saturated liquid, the  oxygen analyzer
         can be calibrated simply by drying
         off the tip of the  oxygen sensor and
         setting the instrument to read  100%
         saturation.

B  Yellow Springs Instrument  Company Probe
   Model 51 Oxygen Meter

   1   Performance data,  oxygen meter
      (Figure  6)
      a Range

        0-25 ppm DO
        0 - 50% DO saturation at 760 mm

      b  Accuracy

         With direct calibration the error is
         less than 1/2% saturation or 0. 25 ppm.
   "O" RING
  MFM8RANE
    ANODE	m
     con       IU-J-
          The YSI Oxygen Probe

             Figure 6

   c  Readability

      0. 2% saturation or
      0. 1 ppm

   d  Response time

      90% of reading in 10 sec. dependent
      on temperature and oxygen level.

   e  Temperature range of Og measurement.
      5 to 45C.

   f  Battery life
      500 hrs.

2  Performance data,  temperature probe

   a  Range 0 -  50C

   b  Accuracy + 1. 5C

   c  Readability 0. 2C

3  Readings below surface of water:

   a  Instrument can be calibrated to read
      directly in % saturation of Oxygen.

   b  If the measurement is to be made
      below the surface of the water, the
      pressure of the water must be taken
      into consideration because the amount
      of dissolved oxygen is related to the
      total pressure of the layer of water
      being analyzed.

   c  Automatic pressure -  compensation
      for sample depth can be effected by
      calibration chamber design.
 7-8

-------
                                                        Dissolved Oxygen Determination
 4   Calibration

    Whenever possible,  calibration should
    be performed at the  same temperature
    as the measurements (Figure 7).

    a  Assemble stopper (3) onto probe (4).
                   10
                Figure 7

          The Direct Calibration Method
   b  Insert probe-stopper assembly into
      top of calibration chamber (5).

   c  Insert stopper (6)  into bottom of
      chamber (5).

   d  Chamber is filled  with air, and con-
      nected to tube (1).  The pressure is
      equalized in chamber at sample
      depth.  Oxygen in  air is measured at
      temperature  of sample.

5  Measurement

   a  Transfer probe stopper from chamber
      (5) to ring (7).
      b  Twist handle to induce flow past
         membrane.

   6  Theory of measurement of YSI oxygen
      probe.

      a  The cathode  is a gold ring imbedded
         in a lucite block.

      b  The anode is a silver coil recessed
         in the center well.

      c  The interior is filled with a solution
         of KC1.

      d  A thin teflon membrane  is stretched
      ^across the end of the sensor.
    ^ff^"^  - ' -S"ai.,w

  >   e  When a suitable polarizing voltage
  {      is applied across the cell, oxygen
   \     will react in the  cathode causing a
         current to flow through the cell.

C  The Galvanic Cell DO Analyzer (Figure 8).

   A lead anode-silver cathode galvanic
   couple.
                             To Microommerer

                             Plastic Casting
                            Plastic Collar
                             Polyethylene
                              Membrane

                               Lens Paper
                            Lead Anode

                            Silver Cathode
      THE GALVANIC CELL OXYGEN ANALYZER
                  Figure 8
                                                                                       7-9

-------
Dissolved Oxygen Determination
   1  Lead is selected as the anode because
      its electrode potential is sufficiently
      negative to cause spontaneous oxygen
      reduction without externally supplied
      voltage.

   2  KOH is the electrolyte.

      a  Residual current is small.

      b  Lead ions are  soluble.

      c  A clean anode  surface is maintained.

   3  Electrode reaction

      a  Cathodic reaction

         O2 + 2H2O + 4e 	^ 4 OH"

      b  Anodic reaction

         pb + 4OH"	^ pbC>2 + 2H2O + 2e

   4  The salt effect

      When the analyzer is  used in water
      samples, a correction factor may have
      to be applied to the  cell sensitivity.

      a  If the oxygen analyzer probe is cali-
         brated in a salt solution identical
         to the salt solution being investigated,
         no correction factor is needed.
        A correction need not be made for the
        "salt effect" in waters having a
        dissolved solid of less than 500 mg/1.
D  Calibration Practice at SEC

   In the water quality surveys, SEC workers
   calibrate all DO probes daily,  using the
   Alsterberg Modification of the  Winkler
   procedure as the standard of comparison./
REFERENCES

1  A Dissolved Oxygen Primer.  Beckman
      Bulletin 7015.  Beckman Instrument,
      Inc.  Fullerton, California.  1962.

2  Precision Scientific Co.  Technical
      Bulletin TS-68850.  Precision Scienti-
      fic Company.  Chicago, Illinois.

3  Instructions for  YSI Model 51 Oxygen
      Meter.  Yellow Springs Instrument
      Company.  Yellow Springs, Ohio.

4  Standard Methods  for the Examination of
      Water and Wastewater.  APHA, AWWA,
      WPCF.   llth ed.  1960.

5  Porges, R.  Dissolved Oxygen Determina-
      tions for Field  Surveys.  WPCF 36,
      1247.   1964.
 7-10

-------
                                LABORATORY PROCEDURES
     J
     DISSOLVED OXYGEN

         D. G.  Ballinger*
I WINKLER METHOD - AZIDE MODIFICATION
A Reagents

   1  Manganous sulfate solution - 364 g
      MnSO4H2O in distilled water, filter,
      dilute to 1 liter.

   2  Alkaline-iodide-azide reagent - 700 g
      KOH and 150 g KI in 950 ml distilled
      water.  Dissolve 10  g NaNs in 40 ml
      distilled water.  Add to alkaline-iodide
      solution with constant stirring.

   3  Sulfuric acid, concentrated

   4  Starch indicator

   5  Sodium thiosulfate solution - 0.025 N

B Procedure:

   1  To a full sample bottle,  with the tip of
      each pipette below the  surface of the
      sample,  add 2 ml manganous sulfate
      solution and 2 ml alkaline-iodide-azide
      reagent.

   2  Replace the  stopper,  rinse under
      running water and mix by inverting
      4-5 times.  Allow  the  precipitate to
      settle.  Repeat the inverting and
      settling.
      With the tip of the pipette
      face of the sample,  add 2
      trated sulfuric acid.
=ibove/the sur-
   Concen-
      Stopper the bottle, rinse under running
      water and mix to dissolve the precipi-
      tate.

      By means of a 200 ml volumetric flask,
      properly  modified, transferj!0_3jnl of
      the treated sample to a 500 ml Erlen-
      meyer flask.
                     6  Titrate with 0. 025 N THIO to a pale
                        straw color, add 2 ml starch indicator
                        and continue titrating to the disappear-
                        ance of the blue color.

                   C Calculation

                     Because of the addition of reagents,  a por-
                     tion of the sample in the bottle has been
                     displaced.  To compensate for this loss
                     of sample, the volume of treated sample
                     titrated must be adjusted as follows:
                           vol. of sample bottle
                                                     X 200
                     vol. of bottle - ml of reagents

                                   = vol.  of sample titrated
                     for the above procedure:
                          300 "
                        300  - 4
              X  200 = 203 ml
   Since the sulfuric acid displaced sample
   which had been beoxygenated by previous
   reaction,  the 2 ml of acid does not enter
   into the correction. When 203 ml of the treated
   sample is titrated with 0. 025 N thio:

       1 ml 0.025 N thio  1  mg/1 DO

II  RIDEAL-STEWART MODIFICATION

A   Reagents

    1  Potassium permanganate  solution -
      6. 39 KMnO4 in 1 liter distilled water.

    2  Potassium oxalate solution - 2 g
                   in 100 ml distilled water.
                      3  Potassium fluoride solution - 40 g
                         KF 2H2O in 100 ml distilled water.

                      4  Manganous sulfate solution  - 364 g
                         MnSO4H2O in distilled water, filter,
                         dilute to 1 liter.
*In Charge, Chemistry, Technical Advisory and Investigations Section, DWSPC, SEC.
December  1965.
                                                      Reviewed
CH.O.do. 19.8.59
                                                        7-11

-------
Dissolved Oxygen Determination
   5 Alkaline-iodide-azide reagent - 700 g
     KO4 and 150 g KI in 950 ml distilled
     water.  Dissolve  10 g NaNs in 40 ml
     distilled water, add to alkaline-iodide
     solution with constant stirring.

   6 Sulfuric acid,  concentrated

   7 Starch indicator

   8 Sodium thiosulfate solution - 0.025 N

B  Procedure

   1 To a full sample bottle, with the tip of
     each pipette below the surface of the
     sample, add 0.7 ml concentrated sul-
     furic acid,  2 ml potassium fluoride
     solution, and 1 ml potassium permanga-
     nate  solution.

   2 Replace the stopper,  rinse under run-
     ning  water,  and mix by inverting 4-5
     times.  If a violet color does not persist
     after mixing,  add more permanganate
     solution in 1 ml increments until the
     color persists for 5 minutes.

   3 With the tip of the pipette below the
      surface of the sample, add potassium
     oxalate solution in 0. 5 ml increments
     until the  sample is free of permanga-
     nate  color.  Note: place sample in dark
     for a few minutes after each addition
     of oxalate.  Avoid excess oxalate by al-
     lowing sufficient  time for decolorization.

   4 When the sample is free of permanganate
      color, with the tip of each pipette below
     the surface of the sample, add 2 ml man-
      ganous sulfate solution and 3 ml alkaline-
      iodide-azide reagent.If a precipitate
      does not form, add an additional ml of
      alkaline-iodide-azide reagent.
      Replace the stopper, rinse under run-
      ning water, and mix by inverting 4-5
      times.  Allow the precipitate to settle.
      Repeat the inverting and settling.

      With the tip of the pipette above the
      surface of the sample, add 2 ml cone.
      sulfuric acid.
   7  Stopper the bottle, rinse under running -
      water,  and mix to dissolve the precipi-
      tate.

   8  By means of a 200 ml volumetric flask,
      properly  modified, transfer 206 ml of
      the treated sample to a 500  ml Erlen-
      meyer  flask.

   9  Titrate with 0.025 N thio to a pale
      straw color, add 2 ml starch indicator
      and continue titrating to the disap-
      pearance of the blue  color.

C  Calculation

   Because of the addition  of reagents, part
   of the sample in the bottle has  been dis-
   placed.  To compensate for this loss  of
   sample, the volume of treated  sample
   titrated must be adjusted as follows
       vol. of sample bottle
                                 X 200
   vol.  of bottle - ml of reagents
                = vol.  of sample titrated
   In the above procedure, a total of 9. 2 ml
   of oxygen-bearing sample was displaced
   by reagents.
         300
     300 - 9.2
                X  200 = 206 ml
   Note: If more than the prescribed amount
   of any of the reagents is required, the
   volume of treated sample for titration
   must be adjusted.

   When the correct volume of treated sample
   is titrated with 0.025 N thio:
                                                        1 ml 0. 025 N thio % 1 mg/1 DO
III THERIAULT (SHORT WINKLER)
   MODIFICATION

A Reagents

   Same as for Azide modification
7-12

-------
                                                           Dissolved Oxygen Determination
B  Procedure

   The Theriault modification consists of the
   Alsterberg modification,  but performed
   as rapidly as possible.  The usual settling
   of the precipitate is omitted and the
   titration is performed immediately after
   the sample has been acidified.
C  Calculation

   The calculation and reporting of results
   for the Theriault modification are the
   same as for the  Winkler Method -
   Azide modification.
                                                                                       7-13

-------
                                 POLAROGRAPHIC ANALYSIS

                                        D. G. Ballinger*
 I   INTRODUCTION

 A  Historical Background

    The polarographic method was first de-
    scribed by Heyrovsky, at Charles Universi-
    ty in Prague, in 1922.  Using the electro-
    chemical laws postulated by Nernst  Prof.
    Heyrovsky developed the principles and
    instrumentation for the current-voltage
    relationships and called the method "po-
    larography". Most of the  concepts and
    design factors have remained unchanged
    to the present time.

    The earliest polarographic instruments
    were a recording type, using photographic
    paper to trace the polarograms.  The
    electrode systems were nearly identical
    to those in use today.

 B  Utility

    The polarographic method, with its as-
    sociated procedures,  is one of the most
    sensitive analytical techniques available.
    It is widely used in research as well as
    in routine analysis.  Since the method is
    relatively new, refinements in technique
    and application are continually appearing.
II  THEORETICAL BASIS

 A  Electrolysis

    Polarography is defined as the electroly-
    sis of a minute fraction of a solution
    around a small easily polarizable elec-
    trode.  The electrolysis is confined to
    that part of the solution which is in con-
    tact with the surface of the small elec-
    trode,  while the body of the solution re-
    mains unchanged.  For purposes of this
    discussion, a polarized electrode is one
    which adopts the potential externally im-
    posed on it, with no change in current.

    The most familiar forms of electrolysis are
    those involved in electroplating baths, or
   in the production of gases at electrodes.
   In all electrolysis,  the chemical reactions
   which occur at the electrodes are  the re-
   sult of the flow of electrons from the ex-
   ternal source  of voltage.  In the galvanic
   cell or battery,  however, chemical re-
   actions in the  cell produce a flow of
   electrons, which is current.

   Consider the case of two platinum elec-
   trodes suspended in a well-stirred solu-
   tion of copper  sulfate.  When an increas-
   ing external voltage is applied, no reaction
   occurs until sufficient electrons are
   available to  reduce  the copper ions;
Cu++
+ 2 e"
= Cu
   When this potential has been reached,  the
   copper ions will "plate out" on the cathode.
   If current measurements are made and the
   current-applied EMF is plotted, the curve
   will appear as:
  Current
                	  Applied EMF 	*-

   After the decomposition potential E^ is
   reached, the reaction follows a straight
   line, the slope being dependent on Ohm's
   Law.  This linear relationship will con-
   tinue until all the copper ions in the solu-
   tion are reduced, since the stirring will
   bring all the ions to the electrode  surface.

B  Limiting Current

   Now consider a similar case, where one
   of the electrodes is very small and the
   other large, and the solution is not stirred.
   Under these conditions, the current will
*In Charge, Chemistry,  Technical Advisory and Investigations Section, DWSPC, SEC.
CH.MET. 12a. 12.65
                                       7-14

-------
Polarographic Analysis
    rise until the concentration of Cu++ ions
    at the surface of the small electrode
    approaches zero. In such a quiescent
    solution,  ions can only reach the elec-
    trode by diffusion.  Further increase in
    applied potential will not increase the
    current linearly, since the  current  is
    now limited by the supply of cupric  ions.
    In fact, the magnitude of the current will
    depend  upon the rate  of diffusion of  ions
    to the electrode surface. A plot of the
    current-voltage curve would appear as:
 Current
                           Limiting
                            Current
                 E
    When the concentration of ions at the
    electrode surface approaches zero, the
    concentration gradient across the inter-
    face approaches a constant.  The value
    of this constant is a function of the con-
    centration of ions in the body of the solu-
    tion.  Under such condition, the  small
    electrode is said to be "concentration
    polarized, " i.e., the  current flowing is
    limited by the concentration gradient of
    a specific ion at the electrode surface.
    In the polarographic method the small
    polarizable electrode  is usually a mer-
    cury drop falling from a capillary.  The
    capillary is selected to yield a new drop
    every 3-5 seconds.  With  each new drop
    a new electrode  surface is provided,
    eliminating all deposition  products from
    the previous electrolysis.  Each drop is
    an exact replicate of its predecessor,
    making the electrode characteristic re-
    producible.

C  Quantitative Use

    The limiting current is actually the sum
    of three separate componentS:the residu-
    al  current, the migration current, and
the diffusion current.  The residual cur- f
rent is the result of electrochemical re-
action at the surface of the small elec-
trode, independent of any specific ion
reaction.   The residual current is nor-
mally very small and is proportional to
applied EMF.  The migration current is
the result of electrostatic  forces  which
cause a flow of positive ions toward the
cathode and negative ions toward  the
anode.  The ions are said  to "migrate"
toward the opposing electrode.  If a large
excess of inert electrolyte is present  in
the sample, the electrical resistance  be-
tween the electrodes is very small and
the current is carried entirely by the  ions
of the inert electrolyte.  However, since
the electrons may reach the electrode
surface only by diffusion,  the current
which flows is very small  and is actually
dependent upon the rate of diffusion.

The diffusion current is the result of
diffusion of the ions into the electrode -
solution interface.   The rate of diffusion
is controlled by the concentration gradient
between the ions at the surface of the
electrode and those in the body of the
solution (Fig. 1).
    CONCENTRATION GRADIENT
             AT D. M. E.
               Figure 1
 7-15

-------
                                                           Polarographic Analysis
Since the effect of the migration current
is negligible and the residual current is
constant at a specific applied EMF, the
diffusion current alone may be considered.
As indicated above,  the diffusion current
is controlled by the concentration gradient,
which is in turn a function of the concentra-
tion of test  ions.  Measurement of the dif-
fusion current  will yield a value directly
proportional to the concent ration in the body
of the solution.  Thus the use of thepolaro-
graph as a quantitative instrument requires
the application of a definite potential and
the measurement of the resulting current.
Figure 2 shows a polarogram of copper
solution at four different concentrations.
Note that the wave height (current) is
directly proportional to the concentration
of copper  in each solution.

In quantitative analysis with the polaro-
graph, the current-concentration relation-
ship  is determined on a series of standard
                            of known concentration.  A calibration
                            curve is constructed and a proportionality
                            factor is calculated, using the equation:
                                     C  =  K  (D  -
                               where:
                                     C   = concentration

                                     K   = proportionality factor

                                     D   = Diffusion current at
                                           C concentration

                                     D   = Diffusion current at
                                      o
                                           O concentration

                            For subsequent determinations of unknown
                            samples, the diffusion current is measur-
                            ed at the same applied EMF and  under the
                            same  conditions  and the concentration
                            calculated from the proportionality.
                    WAVE HEIGHT AT VARIOUS CONCENTRATIONS
                                                    RESIDUAL CURRENT
               O.I
0.2    0.3    0.4    0.5    0.6    0.7
     Figure 2.  NEGATIVE POTENTIAL
              VOLTS VS.  SCE
                                                                                      7-16

-------
Polarographic Analysis
D Qualitative Use

   The decomposition potential E^, at which
   electrode reaction begins, is effected by
   the concentration of reducible ions. How-
   ever the half-wave potential, (the potential
   at which the current is equal to one-half
   of its limiting value) is independent of con-
   centration and specific for the particular ion
   being reduced. It may therefore be used for
   qualitative determination.  Et can be de-
   termined graphically,  as shown in Fig.  3.

   Tables of half-wave potentials are avail-
   able in the literature and are helpful in
   the identification of unknown ions.   From
   these data, the composition  of a mixture
   of several ions may be determined.  The
   polarogram of such as mixture is shown
   in Fig.  4.  Since the supporting electrolyte
                          influences the half-wave potential, the
                          proper electrolyte must be specified.
                      Ill  INSTRUMENTATION

                       A Circuitry

                          As shown in the circuit diagram, Fig. 5,
                          the polarographic instrument has:

                          1  a source of EMF, generally 0-3 volts

                          2  a voltameter for measuring the EMF

                          3  a variable resistance for controlling
                             the applied EMF

                          4  a sensitive galvanometer for measur-
                             ing the resultant current

                          5  a cell, consisting of two special elec-
                             trodes.
                               GRAPHIC DETERMINATION
                               OF HALF-WAVE POTENTIAL
                    0.
0.2    0.3    0.4    0.5    0.6    0.7    0.8
  Figure 3.  NEGATIVE POTENTIAL
           VOLTS,  VS. SCE
09
1.0
7-17

-------
                                                               Polarographic Analysis
Most instruments also incorporate ad-
ditional circuits for reversing polarity,
selecting galvanometer range, or auto-
matically recording the current-voltage
curves. Regardless of the complexity
or cost of polarographic instruments have
the five basic components shown above.
B  Cell
#

   Figure 6 illustrates the electrode as-
   se'mbly normally used in polarographic
   work.  The mercury level, which must
   be held constant, is controlled by the
   leveling bulb.  The cell contains the
                             ^ POLAROGRAM OF MIXTURE
                               NEGATIVE POTENTIAL
                              IP  VOLTS VS. SCE
             0.5  0.6   0.7  0.8   0.9   1.0  1.1   1.2  1.3   1.4  1.5   1.6
                                                                                  7-18

-------
Polarographic Analysis
 B ~^-::-
   TYPICAL POLAROGRAPHIC CIRCUIT
                  Figure 5

   dropping mercury electrode and a reference
   electrode, generally saturated calomel,
   connected by means of a salt bridge.

C  Variables Influencing the Diffusion
   Current

   A study of the relationship of cell design
   to current produced has shown that  the
   current is influenced by several variables:

   1 Size of the mercury drop- the amount
     of current flowing is proportional to
     the surface area of the drop. Therefore,
     drop size must be constant for quanti-
     tative work.  Changes in  capillary size
     or length or in static pressure on the
     mercury will influence the size of the
     drop.

   2 Drop time - For reproducible results
     the life of each drop should be 3-5
     seconds.  Shorter drop time will cause
     stirring action around the electrode;
     longer time will permit interference
     from vibration and adsorption of de-
     composition products.  Drop time is
     affected by capillary characteristics,
     electrolyte composition and concentra-
     tion, applied potential, and pressure on
     the mercury.

   3 Temperature - Changes in tempera-
     ture affect the drop time  and size of
     the mercury drop, the migration cur-
     rent, the rate  of diffusion,  and the
      adsorption of decomposition products.
      Normally the cell and sample are im-
      mersed in a thermostated water bath
      to control temperature fluctuations.
      Where  the sample must be analyzed
      without temperature control, a small
      thermometer is incorporated in the
      electrode assembly and suitable tem-
      perature correction calculated.  Tem-
      perature coefficients have been found
      to be approximately 1. 5% change in
      current for each 1 change in tem-
      perature.

   4  Oxygen Interference - For most polaro-
      graphic determinations it is necessary
      to remove dissolved oxygen from the
      sample.  Oxygen produces a very
      prominent polarographic  wave over
      the region 0.1 - 1.8 volts vs.  SCE.
      Removal of the oxygen is accomplish-
      ed by the addition of alkaline sodium
      sulfite  solution or by bubbling an inert
      gas such as  nitrogen through the sam-
      ple.

   5  Reference Electrode - In  order to
      accurately control the applied  potential
      a reference  electrode must form one
      of the half-cells in the electrode as-
      sembly.  Generally a saturated calomel
      electrode is used.  To prevent a shift
      in the half-wave potential the SCE
      should  be large and the salt bridge
      must have a low resistance junction.

E  Commercially Available  Instruments

   1  Manual Instruments - requiring the
      manual control of the  applied voltage
      through a rheostat.  These are non-
      recording instruments, so that polaro-
      grams  are developed manually from
      galvanometer readings.

      Sargent Model III - Uses  1. 5 v dry
      cells as a source of EMF. Current is
      indicated on a 300 mm. curved scale.
      A moving coil galvanometer measures
      current over a wide range. This instru-
      ment is versatile, yet has accuracy
      comparable  to more expensive models.
      It is suited to routine laboratory analysis
7-19

-------
                                                         Polarographic Analysis
         Wire
      Leveling
        Bulb
                                Glass Bulb
	Mercury
    Level
      Plastic Tubm
                                             Gloss Tubing
                                                Plastic Tubing
                                                      --Wire
ELECTRODE  ASSEMBLY
                                                         Rubber
                                                           Cap
           Glass


           Saturated
           Colonel Electrode
                        Capillary
                                                    Glass
                                                	Sample
                               Figure 6
                                                                           7-20

-------
Polarographic Analysis
      and may be adapted to rotating elec-
      trodes.   . .. $475.

      Fisher Electropode - A compact, self-
      contained manual instrument.   The cell
      and electrode assembly are mounted on
      the  front of the cabinet, but may be dis-
      mounted for use in a water bath or
      special  cell.  The galvanometer as-
      sembly  is rugged enough to make the
      instrument portable.    . . . $615.

      Recording Instruments - these auto-
      matically apply an increasing  potential
      at a constant rate.  The movement of
      the  chart recorder is synchronized
      with the voltage divider so that the cur-
      rent -  voltage curves are correctly
      plotted.

      Sargent Model XXI - a pen recording
      instrument,  providing maximum ver-
      satility.  The polarogram is recorded
      on roll type chart.  A good instrument
      for research in electrochemical re-
      actions.    ...$2580.
      Sargent Model XV - a good instrument,
      having all the necessary features at a
      reasonable price.  This polarograph
      can be adapted to the use of the Micro-
      range Extender (Sargent) yielding sen-
      sitivities to 0. 0001 ua/mm.  . . . $1585.
REFERENCES

1  Kolthoff, I. M., and Lingane,  J. J.  Polaro-
      graphy.   Interscience Publishers.   New
      York.  1952.

2  Muller, O. H.  The Polarographic Method
      of Analysis.  Journal of Chemical
      Education.  Eaton, Pa.   1941.

3  Meites, Louis.  Polarographic Techniques.
      Interscience Publishers.  New York.
      1955.

4  Milner, G. W. C.  The Principles and
      Applications of Polarography and Other
      Electroanalytical Processes.  1957.
7-21

-------
                                                                                S_r> /
                                                                                &   py &)
           POLAROGRAPfflC DETERMINATION OF DISSOLVED OXYGEN FOR BOD
                                          N.  C. Malof*
 I  EQUIPMENT

 A Recording Polarograph, /vith dropping
    mercury electrode (approximately 3 sec-
    onds) and saturated calomel electrode.

 B Sample bottle,  125 ml glass stoppered.
 II  REAGENTS

 Electrolyte -  dissolve 0. 375 g methyl red
 and 0. 2 g KOH in 50 ml distilled water.  Add
 18. 75 g KC1 and  dilute to 100 ml with distilled
 water.
Ill  SAMPLE PROCEDURE

 A Instrument

    1  Turn instrument on and allow approx-
       imately 20 minute warm-up.

    2  Check instrument  (daily) as described
       in Part C.

    3  Check sample temperature.  Should be
       19-2lC.

    4  Add  0. 5 ml electrolyte, below surface
       of sample.  Stopper with rubber stopper
       and mix.

    5  Set instrument:
       Sensitivity 0. 020    Range 0 to -1 volts

    6  At 0 Applied voltage, adjust recorder
       pen to 10 mm line on chart with dis-
       placement  control.

    7  Set Applied voltage to 40%.  Allow pen
       deflection to  stabilize until peak heights
       are equal.

    8  Set Applied voltage to 0.

    9  Measure total mm peak height and
       subtract 10 mm.
   10  Using calibration table,  calculate DO
      in mg/1.  Repeat steps 3 to 10 for
      each sample.

 B Standard Curve and Calibration Table

   1  Prepare a series of at least 10 samples
      having a range of DO values from
      1-9 mg/1 by bubbling nitrogen gas
'  '   through tap water.

   2  Fill duplicate  bottles,  using 125 ml gas
      stoppered bottle for polarographic
      determination and standard BOD bottle
      for Winkler method.

   3  Determine peak height on each standard,
      as in steps  3-8 in Sample Procedure.

   4  Determine DO by Winkler method on
      corresponding bottles.

   5  Plot peak height vs Winkler DO on
      linear graph paper.

   6  Using method  of least squares, find
      equation for line of best fit.

   7  Using equation of best fit, prepare a
      table for converting mm peak height to
      mg/1 DO.   This table is only valid for
      the electrodes and mercury height used,
      and for  the  sample  temperature at
      which the peak heights were measured.

 C Daily Instrument Check

   1  After approximately 20 minutes warm-
      up, turn Operation  control to Release
      Chart position.

   2  Check standardization by holding
      "Standardization" control first to Volt-
      age,  then to Current, observing pen
      travel.   Pen should  move slowly to left
      on Voltage and on Current.  If necessary,
      adjust pen travel with appropriate
      controls.
 #Chemist,  Technical Advisory and Investigations Section, DWSPC, SEC.

 CH.O.do.27a. 12.65                                                                    7-22

-------
Polarographic Determination of DO jor BOD
   3  Turn Cell control to Rs (standard
      resistor) .

   4  Set Voltage Range to 0 to - 1 volts,
      Voltage Applied toj) and sensitivity to
      0.020.

   5  Adjust pen to 10 mm line on chart with
      displacement control.

   6  Turn Operation control to Record and
      place pen on paper.

   7  Turn Voltage Drive control to 0 to 100%.

   8  Pen should trace a straight line, sloping
      sharply to left.
      For sample, adjust mercury height to
      mark, check to see that mercury is
      flowing in regular drops.  Turn Cell
      control to Normal Polarity.
IV  LABORATORY EXERCISE FOR
    BOD PROCEDURE

    Place  1 liter of effluent into 4 liter bottles,
    add 3 liters of dilution water (25% dilution).
    Mix and aerate with diffuser and syphon
    into 10 large (300 ml) DO bottles  and 5
    small  (125 ml) bottles.

  Run initial Winkler DO on large DO  bottles
  and incubate the other  8 bottles.  Run initial
  polarograph DO on  1 small bottle and incubate
  the other 4 bottles.   Run Winkler and polaro-
  graph DO according to the following schedule:
  Plot Summation (S) of each Winkler DO
  determination (ADO) obtaining a 7-day BOD
  curve.  Determine k rate by the Moment's
  method using a time (t) of 7 days.  Repeat
  plot and calculations for polarograph DO
  determinations.
                                               DAYS
                              Initial  Wed.  Thurs.  Fri.  Sat.  Sun.  Mon.  Tues.
Day
Bottles
iWinkler
Bottles

Polarograph
0
2



1
2



2
2



3456
2222



7
2



 7-23

-------
                        DISSOLVED OXYGEN PROBE LABORATORY

                                       N. C.  Malof*
I  CALIBRATION OF DISSOLVED
   OXYGEN PROBE

A  Precision Scientific

   1  Prepare duplicate DO samples and run
      one of them by the Winkler Method.

   2  Place a stirring bar in other bottle and
      set it on magnetic stirrer.

   3  Check thermistor by turning  large knob
      on meter to "temperature adjustment".
      Turn needle to 40C on meter with
      smaller "temperature adjustment" knob.

   4  Measure temperature of  sample with
      thermistor.

   5  Remove thermistor from bottle and
      insert probe.  Turn on magnetic stirrer
      to 1/2 or 3/4 speed being careful not to
      cause air bubbles.

   6  Turn knob to "oxygen"  and read  "ua" on
      2 scale.

   7  Divide  "ua" by Winkler DO value and
      this gives the sensitivity coefficient

                      ua
                ^     DO

   8  To determine DO of unknown sample,
      divide ua by .


               D0  =   f

      This meter is not temperature com-
      pensated and does not read direct DO in
      mg/1.  A new sensitivity coefficient (4>)
      must be calculated for  each temperature
      and calibration should be checked every
      day.
                                                 B Yellow Springs, Inc.

                                                    1  Prepare duplicate DO samples and run
                                                       one of them by the Winkler Method.

                                                    2  Place a stirring bar in other bottle and
                                                       set it on a magnetic  stirrer.

                                                    3  Check thermistor by turning knob to
                                                       read "red line" and then using adjust-
                                                       ing screw, set needle to  red line on
                                                       meter face.

                                                    4  Measure temperature of sample with
                                                       thermistor.

                                                    5  Remove thermistor from bottle  and
                                                       insert probe.  Turn  on magnetic stirrer
                                                       to 1/2 or  3/4 speed being careful not to
                                                       cause air bubbles.

                                                    6  Turn knob to "read"  and adjust meter
                                                       to same DO value as Winkler.  The
                                                       meter is now direct  reading in mg/1
                                                       DO.

                                                       This meter  is not temperature com-
                                                       pensated but does read directly  in mg/1
                                                       DO.  A temperature  factor must be
                                                       applied at other temperatures.

                                                       The calibration of this probe should be
                                                       checked daily.

                                                 C Weston and Stack, Inc.

                                                    1  Prepare duplicate DO samples and run
                                                       one of them by the Winkler Method.

                                                    2  Check the thermistor by turning knob
                                                       on front of meter to  "temperature". Push
                                                       "temperature check" button on left
                                                       side of case and needle should read
                                                       50C.  If not,  turn "temperature adjust-
                                                       ment" screw on right side of case.
*Chemist,  Technical Advisory and Investigations Section,  DWSPC, SEC.
CH.O. do.lab. 2. 12.65
                                                                                       7-24

-------
Dissolved Oxygen Probe Laboratory
      Insert probe into bottle making sure that
      micro-switch on side of probe closes
      and that vibrator on probe is moving.
      Read temperature by turning knob to
      "temperature".

      Turn knob to "DO 1-mult"1" and set
      needle to read same value as  Winkler
      DO.  The meter is now direct  reading
      in mg/1  DO at any temperature.

      This meter is temperature compensated
      and will read directly in mg/1  DO.  A
      calibration check should be performed
      daily.
REFERENCES

J  Precision Scientific Co.  Technical Bulletin
      TS-68850.  Precision Scientific Compan:
      Chicago,  Illinois.

2  Instructions for Y.S.I. Model 51 Oxygen
      Meter.  Yellow Springs Instrument
      Company, Yellow Springs, Ohio.

3  Instruction for Weston and Stack Model
      300 Dissolved Oxygen Probe.  Weston
      and Stack, Inc., Newtown Square,
      Pennsylvania.
7-25

-------
,  3
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3.  ij

                          // c^
                                                       /32_
                                                           7.9
                                                                                  .)
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                                            -c- 3

-------
                                 BOD TEST PROCEDURES
                                      D.G. Ballinger*
I  DIRECT METHOD

A  Application

   With relatively clean surface waters the
   BOD may  be determined by incubation of
   the undiluted sample for the prescribed
   time interval.  This method is applicable
   only to those waters whose BOD is less
   than 8 mg/1.  If the waste is known to be
   lacking in proper biota the seeding pro-
   cedure in  III should be used.

B  Procedure

   1  Fill three 300 ml glass  stoppered bottles
      with the sample,  making sure that no
      air bubbles are entrapped and that the
      bottles are filled to overflowing before
      inserting the stoppers.

   2  Determine the DO concentration on one
      of the bottles by the appropriate Winkler
      modification.  This concentration is
      reported as  "initial DO".

   3  Incubate the two remaining bottles at
      20 C in complete darkness.  The in-
      cubated bottles  should be water-sealed
      by inversion in  a tray of water or by
      using a special  water-seal bottle.

   4  After 5 days of  incubation,  determine
      the DO on the two bottles.  Average
      the DO concentration  of the duplicates
      and report as "Final DO".
    5  Calculation

      Initial DO - Final DO = 5 day BOD in
      mg/1.
II   DILUTION METHOD - UNSEEDED

 A  Application

    Where the BOD of the sample is greater
    than 8 mg/1,  the  sample must be diluted
    to a concentration which will yield a DO
    depletion less than that amount in 5 days.
    Suggested dilutions are shown in the table
    below:

    If the waste is known to be lacking in
    proper biota the seeding procedure in III
    should be used.

 B  Procedure - Bottle Dilution  Technique

    1  Using an assumed or estimated BOD
      value as a guide, calculate the appro-
      priate factors  for a range of dilutions
      to cover the  desired depletions.  De-
     j3jJaonJutxj^^Apfie,LiQ. -. 90% qf the
      initial DO  will give the most reliable
      results.
                        ____
      less than J^mg/1 or_inore,thanm8^mg/l
      may not be reliable.  At leasf three  ^^
      dilutions in duplicate should be  used.

      Accurately measure the required amounts
      of sample into 300 mlglass stoppered bottles.
Type of Waste
Strong Industrial Waste
Normal Sewage
Treated Effluents
Polluted Surface Waters
Estimated 5 day BOD
500 - 5000
100 - 500
20 - 100
5-20
Dilution
0.1- 1%
1 - 5%
5 - 25%
25 - 100%
*In Charge, Chemistry, Technical Advisory & Investigations Section, DWS&PC, SEC.
December  1965.
                                   Reviewed
CH. O. bod. 43a. 8.63
                                       3-1

-------
BOD: Test Procedures
      Fill the bottles completely with dilution
      water (Standard Methods l*h Edition
      page &c&T.               \ "
      Using the appropriate Winkler modifi-
      cation, separately determine the DO
      concentration of the waste and the di-
      lution water and calculate the "initial
      DO".  If the waste represents 1% or
      less of the total volume,  or it is known
      to have a DO of practically zero, the
      calculation should be based on the DO
      of the dilution water.

      Incubate the bottles at 20C in complete
      darkness.  The incubated bottles should
      be water-sealed by inversion in a tray
      of water or by using a special water-
      seal bottle.

      After 5 days of incubation determine the
      DO on the bottles. Average the DO con-
      centration of the duplicates and report
      as "Final DO".
   7  Calculation:

   (Initial DO - Final DO) X
300
                           ml waste per bottle

                     = 5 day BOD in mg/1

C  Procedure - Cylinder Dilution Technique

   1  Using an assumed or estimated  BOD
      value as a guide,  calculate the factors
      for a range of dilutions to cover the
      desired depletions.  Depletion in the
      range of 40 - 90% of the initial DO will
      give the most reliable  results.  Dilutions
      showing final DO less than 1 mg/1 or
      more than 8 mg/1 may not be reliable.
      At least three dilutions in duplicate
      should be used.

   2  Into a one liter graduated cylinder (or
      other similar container)  measure ac-
      curately the required amount of sample
      to give one liter of diluted waste. Fill
      to one liter mark with  dilution water
      (Standard Methods, 'ilth  Edition, page
      319).  Carefully mix by stirring, avoid-
      ing the entrapment of air bubbles.
                    3  Siphon the mixture from the cylinder
                       into three 300 ml glass stoppered bot-
                       tles, filling the bottles to overflowing.

                    4  Determine the DO concentration on one
                       of the bottles by the  appropriate Winkler
                       modification and record as "Initial DO".

                    5  Incubate the two remaining bottles at
                       20C in complete darkness.  The  incu-
                       bated bottles should  be water-sealed by
                       inversion in a tray or by using a special
                       water-seal bottle.

                    6  After 5 days of incubation, determine
                       the DO on the bottles.  Average the DO
                       concentration of the  duplicates and re-
                       port  as "Final DO".
                    7  Calculation

                    (Initial DO - Final DO) X
                                  1000
                                             ml sample used

                                       = 5 day BOD in mg/1
III DILUTION METHOD - SEEDED

 A  Application

    Many industrial wastes are sterile, due to
    their chemical composition or the manu-
    facturing process involved.  These wastes
    must be seeded with the proper type  and
    number of  organisms to obtain correct
    BOD values.  The seed may be stale do-
    mestic sewage, stream water, or an accli-
    mated culture complex.

 B  Procedure

    1  Calculate the percentage of seed re-
       quired to produce at least 0. 6 mg/1
       5 day BOD.

    2  Calculate the proper waste  dilutions as
       in II  B or II C above.  Reduce the con-
       centration of waste sufficiently to allow
       for the seed depletion.

    3  Measure the required  amount of waste
       as directed in II B or II C.

-------
                                                                  BOD:  Test Procedures
\  Add approximately half of the required
   amount of dilution water to the sample.
   This is necessary to assure that the
   concentrated waste does not exert a
   toxic effect on the seed organisms.

5  Measure the calculated amount of seed
   into the  bottle or  cylinder and fill with
   dilution water. Siphon into bottles  if
   using the method  in II C.

6  Calculate (n-B-4) or determine (II-C-4)
   the initial DO.

7  Incubate the bottles at  20C in complete
   darkness.  The incubated bottles should
   be water-sealed by inversion in a tray
   of water or by using  a  special water-seal
   bottle.

8  After 5 days of incubation,  determine
   the DO on the bottles.  Average the DO
   concentration of the duplicates and re-
   port as  "Final DO".

9  Calculations
                                         /
   Seed Correction

   The value applied as a seed correction
   is obtained by determining  the BOD of
   the seed itself.  Either the Direct Method
   (I-B) or the Dilution  Method (II-B or H-C)
   may be used, depending upon the strength
   of the seed material.   It is essential that
   enough seed is used to produce normal
   demand.   Generally, a depletion of 3-6
   mg/1 in 5  days indicates satisfactory de-
   oxygenation.  The following formula is
   used for the seed correction:
Depletion in
seed correction X
bottle
%seed added to sample
% seed used for seed
   correction deter.
               =  Seed Correction

   BOD Calculation

   (Initial DO - Final DO - Seed Correction)"

   X Dilution Factor = BOD,  - of the Waste
  Example:

    Data

      Waste dilution used               2%

      Seed cone, used                0.4%

      Seed correction cone.             3%

      Initial DO                      9.0%

      Final DO                      3.0

      Seed correction depletion       6. 8

    Seed Correction

      6.8X^1 = 0.9 mg/1
             O

    BOD Calculation

      K9.0 - 3.0) - 0.9JX 50

      =  255  mg/1 5 day BOD


IV IMMEDIATE OXYGEN DEMAND

 A  Application

    In certain industrial wastes reducing agents
    such as sulfites, sulfides, or ferrous iron
    will cause an immediate chemical demand
    on the DO.  In order to arrive at the true
    biochemical demand it is necessary to
    differentiate between the two demands.

 B  Procedure

    1  Prepare additional duplicate bottles of
      each of the dilutions used in the standard
      BOD test.

    2  Determine the initial DO as directed
      above.

    3  Incubate the  immediate demand bottles
      for 15 minutes.

    4  Determine the final DO on these bottles
      and calculate the 15 minute depletion.
      Record as "Immediate Oxygen Demand".
                                                                                     8-3

-------
BOD: Test Procedures
    5  Calculation

       Total Demand - Immediate Demand
                     = 5 day BOD


 V  PRECISION OF THE TEST

 Precision of the BOD Test depends upon the
 precision of the DO determinations involved
 and the reproducibility of the biological activi-
 ty in the individual bottles.   Standard deviation
 of the test has been calculated  as 0.07  - 0. 11
 ml of oxygen demand titrated.  That  is, the
 individual BOD value is correct to approxi-
 mately
                    0.09	
        Decimal Fraction of Sample Used


VI  REAERATION  METHODS

 A Application

    Because  the dilution method does not re-
    produce the waste concentrations  which are
    found under natural conditions, some inves-
    tigators advocate incubation of the undiluted
    sample with periodic  reaeration when de-
    pletion has  reduced the DO to approximately
    1.0 mg/1.

 B Procedures

    1  Elmore Method

       A relatively large volume of the sample
       is stored in an unsealed bottle.  Small
                                                       bottles are withdrawn in sets of 5 or
                                                       more,  sealed,  incubated, and the DO
                                                       determined at appropriate intervals.
                                                       When the DO concentration in the
                                                       smaller bottles reaches 1.0 mg/1 a
                                                       new set is withdrawn from the large
                                                       unsealed bottle.

                                                    2  Orford Method

                                                       The deoxygenation is carried out in a
                                                       large sealed  jug from which samples
                                                       for DO are withdrawn at appropriate
                                                       intervals.  To  maintain the waste level
                                                       and a sufficient DO in the jug, additional
                                                       waste is added from a second open
                                                       container.

                                                 C Advantages and  Limitations

                                                    1  All dilution water problems are elimi-
                                                       nated in these methods.

                                                    2  The limitations imposed by the limited
                                                       solubility of oxygen are removed.

                                                    3  The test is generally more representative
                                                       of stream conditions.

                                                    4  Toxicity is not readily apparent, and
                                                       may escape detection.

                                                    5  In spite of the greater range, the methods
                                                       are restricted to rather low BOD (<50
                                                       mg/1 5 day BOD).
5-4

-------
                                                      BOD:  Test Procedures
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-------
BOD: Test Procedures












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-------
                           EFFECT OF SOME VARIABLES ON BOD

                             D. G.  Ballinger and J. W. Mandia*
I  TIME

A  Importance

   An examination of the basic BOD equation,
   y =	L (1__- 10~K"i), and the resultant ex-
   ponential curve, will emphasize the im-
   portance of time in the  oxidation reaction.
   The amount of oxidizable material  react-
   ing at time "t" depends upon the time in-
   terval between the beginning of the reaction
   and time "t".  Obviously,  the  longer the
   elapsed time, the  more nearly complete
   the reaction, but  the percentage of avail-
   able material involved in unit  time is con-
   stant throughout the whole period of
   oxidation.

B  5 Day BOD

   In the interest of standardization of the
   test procedure, the 5 day interval has been
   selected as the  elapsed time.  At 5 days
   the initial lag period often encountered has
   been passed and the reaction has attained
   its normal rate.  However,  the  oxygen
   demand at 5 days is only a part  of the total
   demand of the waste material; it is mere-
   ly a reference point on the oxidation curve.
   -L iTC VcLLUG ODTSLltlGQ Lt 3 Cl3.yS IjQUSX uG 1H""
   terpreted in light of the velocity constant
C  Determination of Constants

   When y values are obtained at equal time
   intervals during the  oxidation reaction,
   these values may be used in the determi-
   nation  of the constant "k" and "L".  To
   insure  accurate  demand values, it is es-
   sential that the time intervals be carefully
   controlled.  This is  especially true  of the
   early periods, when a few hours may pro-
   duce large changes in demand.

D  Complete Oxidation

   Theoretically, the time required for com-
   plete satisfaction of the BOD is infinitely
   long.
                                                                          -IH-
                                                            y  =  L(l - 10 Kt)

                                                     when   y =  L, the quantity 1-10

                                                                 -kt
                                                     therefore: 10    =0 and t = 
                                        = 1
    The practical time for complete oxidation
    can be determined experimentally.   For_
    domestic sewage morethan 100 days is
    necessary; for some industrial waste ma-
    terials a much longer period may be
    required.

II   TEMPERATURE

 A  Effect on Oxidation Rate

    Temperature is one of the important con-
    trolling factors in  any biological system.
    In the BOD reaction, changes in tempera-
    ture produce acceleration or depression
    of the rate of oxidation.  Figure 1 shows
    the  changes in the  value of k at temper-
    atures from 0  - 25C.

 B  Test Temperature

    In the BOD test procedure an arbitrary
    temperature must  be selected, in order
    that the test may be reproducible.  Though
    a wide temperature range exists under
    natural conditions, 20C has been chosen
    as  representing the median temperature.
    Incubation of the test containers at  20C
    for the whole period is now accepted
    practice.

 C  Temperature  Correction

    When it is necessary to calculate the rate
    of oxidation at a temperature other  than
    20  , the following  relationship may be
    used:
                           - T2>
*In Charge, Chemistry,  Technical Advisory & Investigations Section,  DWS&PC, SEC,  and
Chemist,  DWS&PC Training Activities,  SEC.  Reviewed December 1965.
CH. O.bod. 42a. 8.65
                                      3-7

-------
BOD:  Effect of Variables
                  5   M   15   30   35
                    DEGREES C

                  'k WITH CHANGE IN TEMPERATURE
where;
      k = velocity constant at temperature T-^

      k0 = velocity constant at temperature T0
       &                                   &
      9 = temperature coefficient, for which
          Streeter and Phelps obtained the
          value 1.047.
                                                 HI pH

                                                  A Effect on BOD

                                                    The organisms which accomplish the bio-
                                                    chemical oxidation of organic matter are
                                                    acclimated to a narrow pH range.  The
                                                    normal range for these organisms is pH
                                                ^ ,' 6.5 - 8. 3.  Outside this range, the rate
                                                    oif ISidation is depressed.  Figure 2 illus-
                                                    trates the 5 day BOD values obtained from
                                                    pH 4. 5 -  9.0.

                                                  B Adjustment of Concentrated Samples
    When wastes are more acid than pH 6, 5
    or more alkaline than pH 8. 3, adjustment
    to pH 7. 2 is necessary before reliable BOD
  1  values can be obtained.
 C  Dilution Samples

    In the dilution technique, the Formula C
 JL dilution water is buffered at pH 7. 2.  To
  '  insure proper pH control, the sample-di-
    lution waterrmixfure"should be checked.


IV  ESSENTIAL MINERAL NUTRIENTS

 A  Importance

    In 1932 Butterfield investigated the role of
    certain minerals  in the biochemical oxida-
    tion of sewage and concluded that a balanced
                      pH   8
                     4   56   7   8   9   10

                     Time in Days

              Effect of Mineral Nutrients on BOD

-------
                                                                   BOD:  Effect of Variables
   mineral substrate was necessary for normal
   oxidation.  In addition, he found that the lack
   of adequate nitrogen and phosphorus pro-
   duced low BOD values.  (Figure 3)

   With some industrial wastes, the addition
   of nitrogen and phosphorus significantly
  ' increases the efficiency of BOD satisfaction.

B Standard Methods Dilution Water
   The dj.iu,ti.p.a
   test is designed to grpYide^ the essential
   mineral nutrients (including N and P) in
   approximately the concentrations found in
   rialuraTwafer.
V  MICROBIOLOGICAL POPULATION

A  Need for Complex Flora and Fauna

   The  work of Butterfield, Purdy, and
   Theriault in 1931 demonstrated that the
   biochemical oxidation process is accom-
   plished by a complex action involving bio-
   logical forms.  Their data is summarized
   by the graph in Figure 4.  Note that the
   highest BOD values were obtained when the
   normal mixed population was used.  Later
   studies have emphasized the need for an
   adequate mixed biota in  BOD evaluation.

B  Acclimatized Organisms

   Early investigations into the mechanism
   of the BOD dealt primarily with domestic
   sewage.  In this waste the organisms neces-
   sary for  oxidation are present initially in
   adequate numbers and variety.  Streams
   receiving domestic wastes are populated
   by biological forms which are able to readi-
   ly utilize the  organic matter as food.

   With the  expansion of industry in the past
   20 years, new and  complex waste materials
   were added to the receiving streams, cre-
   ating new environmental and nutritional
   conditions.  In most cases the receiving
   streams  have adapted to the new materials
   through the development of acclimated popu-
   lations.  With certain exceptions,  the or-
   ganisms  which exist in the stream at some
   distance below a particular industrial out-
   fall are those which are acclimated to the
   waste and can satisfactorily accomplish
   the biochemical oxidation of that material.

C  Seeding

   In the laboratory determination of the BOD,
   it is ess^nEariHaFWe "prgaijisiiii, present
   in the sample bottle during,.incubation be
   similar in type and numbers to those which
   will oxidize the waste unter natural con-
   ditions.  As indicated above,  dome Silt
   sewage and surface waters contain the
   proper biota.  Many industrial wastes, how-
   ever, are lacking in biological activity
   initially and the samples must be "seeded"
   with organisms before incubation in the
   BOD test.  The  selection of the proper
   seed is a prime requisite for accurate BOD
   evaluation.
                    All forms in river water
                    Mixed bacteria & plankton
                    Pure culture B. Aerogenes
                    Mixed culture bacteria
                    Pure culture B Aerogenes
                   5  6   7
                    Time in Days
          Effect of Biological Forms on Oxygen Depletion
                     Figure 4

-------
 BOD: Effect of Variables
D  Sources and Types of Seed
      Stale Sewage
      For waste samples having organic corny
      position similar to sewage, the most
      reliable seedis domestic sewage which
      has been stored at 20C for approximate-
      ly 24 hours. During the storage period
      the organisms typical of fresh sewage
      have been supercededby a population
      representative of the oxidation stage. In
      order to maintain an aerobic condition,
      it is sometimes necessary to aerate the
      sewage during the  storage period.

2  Stream Water

   The adaption of receiving water to in-
   dustrial effluents has been mentioned
   in C above.  Because of the acclimated
   organisms present below the outfall,
   such streams offer an excellent source
   of seed for the BOD determination. With
   few exceptions, carefully selected seed
   from the receiving stream will yield the
   highest BOD values.   When stream water
   is used for seed,  nitrification difficulties
   (Vn)  may increase.

3  Special Seed

   Occasionally, because of the exotic nature
   of the industrial waste,  it is necessary
   to artificially develop a culture complex
   which will oxidize the waste material.
   This is done by starting with a large va-
   riety of organisms (as in sewage)  and
   feeding the culture with gradually in-
   creasing amounts of  the waste until an
   acclimatization process has produced
   organisms especially adapted to utiliza-
   tion of the waste components. Such a
   culture is obviously an excellent seed
   for use in BOD tests on the particular
   waste.

   In waste treatment facilities, the same
   procedure is followed and similar accli-
   matization occurs.  Effluents from such
   installations can also be used as seed in
   the BOD test.
E  Quantity of Seed Required

   The amount of seed required to produce
   a normal rate of oxidation must be deter-
   mined experimentally.  The most frequent
   error is the use of insufficient seed.

   Figure 5 illustrates the work of Ludzack
   in the determination of satisfactory seed
   concentrations.  When 0.1% seed was
   used a definite lag period occurred.  In-
   creasing the seed concentration to 0. 2%
   eliminated the lag. Further increase in
   seed did not increase the oxidation rate.
   Obviously the concentrations used in this
   study would not necessarily apply to other
   wastes and other seed types.

   Calculation of the ratio of the 2-day and
   the 5 -day BOD values will indicate the
   proper quantity of seed.  The table in
   Figure 5 shows the 2/5  day ratio for each
   of the seed concentrations used.  When the
   0.1% seed was used a low ratio was ob-
   tained,  indicating a lag period.  When the
   proper quantity of seed was used (0. 2 &
   0. 5%) the ratio was higher and remained
   essentially constant.
                                                                T	1"
                                                                              5 DAY
                                                                              BOD
                                 2 DAY
                                 5 DAY
                                                                1   1   I    I   1   I   1  _-L.
                                                          I   ?   1   4   i    (-780   10
                                                                 DAYS INCUBATION @ ?0C
                                                         EFFECT OF SEED CONCENTRATION ON THE  B 0 D OF
                                                          GLUCOSE - GLUTAMIC ACID PRIMARY STANDARD
                                                                   HGURF 5
  8-10

-------
                                                                     BOD:  Effect of Variables
   The actual value of the 2/5 day ratio de-
   pends upon the k rate and is a. function of
   the biological  availability of the waste ma-
   terial.  It is therefore necessary to de-
   termine the proper seed concentration for
   the particular waste-seed combination to
   be used.

   As a rule of thumb for the seed concen-
   tration, at least 0. 6 mg/1 of the 5 day BOD
   should be due  to the seed inoculum. Larger
   seed demands are not objectionable but
   tend to reduce the amount of oxygen avail-
   able for the waste itself.

F  Algae

   When large numbers of algae are present
   in stream waters, they produce significant
   changes in the oxygen content.  Under the
   influence of sunlight oxygen is given off,
   while  during hours of darkness the algae
   utilizes oxygen in their respiration. These
   diurnal fluctuations in DO influence the
   BOD of the stream water.  In sewage sta-
   bilization ponds the BOD of the waste is
   satisfied primarily through the production
   of DO by algae.

   When stream samples containing algae are
   incubated in the laboratory the algae sur-
   vive for a time,  then die because of the
   lack of light.   Short term BOD determi-
   nations may show the influence of oxygen
   production by  the algae.  When the algae
   are dead they  contribute to the total or-
   ganic  content of the sample and increase
   the BOD.  Therefore samples incubated
   in the dark may not be representative of
   the deoxygenation process in the stream,
   since  the benefits of photosynthesis are
   lacking.  Conversely, samples incubated
   in the light,  under conditions of continual
   photosynthesis, will yield low BOD values.

   The influence  of algae in the BOD  is one
   of the most difficult variables to evaluate.
   More  research is needed to develop satis-
   factory methods for the accurate deternii-
   nation of BOD in the presence of large
   numbers of algae.
IV  TOXICITY

 A Effect

    Since satisfaction of the BOD is accom-
    plished through the action of micro-
    organisms, the presence of toxic sub-
    stances will result in depression  of the
    oxidation rate.  In many cases, toxicity
    will produce a lag period, until resistant
    organisms have evolved.  Figure 6  shows
    the effect of cyanide on the BOD curve.  A
    prominent lag period is exhibited in the
    2 ppm curve,  while at 10 ppm the lag ex-
    tends beyond the fifth day.

    Heavy metals  reduce biological activity
    and resistant organisms are seldom de-
    veloped.  The effect of copper and chromi-
    um are illustrated in Figure 7.
       012       34
                   Time in Days
         Kffect of Cyanide on BOD of Domestic Sewage
           (2% Sewage in Formula C Dilution Water)

-------
  BOD:  Effect of Variables
 B  Detection

    In laboratory determinations of BOD  the
    absence of toxic substances must be es-
    tablished before the results can be accepted
    as valid.  Comparison of BOD values for
    ranging dilutions of the waste will indicate
    the presence or absence of toxicity.  In the
    following table the calculated BOD for the
    dilutions show higher values in the more
    dilute concentrations.  It is apparent that
    toxicity is present and that it becomes
    less  with higher waste dilution, resulting
    in more complete oxidation.

                   Table I
Dilution
10%
5%
2%
1%
0.5%
Depletion
3.51
4.53
2.80
1.52
0.74
5 day BOD
35
91
140
152
148
VII NITRIFICATION

 A Mechanism

    The oxidation process,  as exemplified by
    the equation:
            y = L(l-10~kt)
    involves the oxidation of carbonaceous
    matter:
                   O
          C H O
           x  y z
C0
H20
    The constant k is normally high, giving
    nearly complete oxidation in a few days.
    When nitrogenous material is present its
    oxidation can be shown as:
                O2        O2
          NH    -  N0   -   N0
    The rate constant is usually less than in
    the case of the carbonaceous matter.
                        Under some circumstances these two oxi- "
                        dations can proceed simultaneously and
                        the resultant BOD curve will be a compo-
                        site of the two reactions.  Normally,  how-
                        ever, the nitrification stage will not begin
                        until the carbonaceous  demand has been
                        partially satisfied, yielding a curve simi-
                        lar to that in Figure 8.  Theriault suggested
                        that carbon dioxide, produced in the first
                        stage, is necessary for efficient oxidation
                        of the nitrogenous material.  Mathemati-
                        cally the reactions can be described by the
                        equation:

                        y =  L[ a (l-!0"kt) +  b (l-lo"kt)]

                     where:

                        a = high rate constant for  carbonaceous

                        b = low rate constant for nitrogenous

                       k1 = velocity constant for carbonaceous

                       k. = velocity constant for nitrogenous
                        Nitrification occurs most often in effluents
                        and streams which have undergone partial
                        oxidation of the waste components. In these
                        cases the total BOD (carbonaceous + nitro-
                        genous) is not representative of the degree
                        of treatment required.

                        Since nitrification represents a  demand
                        on the oxygen resources of the receiving
                        stream, it  should be recognized as part
                                  T	T
                                   1	r
                                                     -i	r
                                  EFCECT OF N.TO FICA^'ON 0^ B 0 D
                                         ^'CURE 8

-------
                                                                    BOD:  Effect of Variables
     of the total demand of the waste.  Because
     of the variable occurrence of the reaction,
     however, comparison of BOD values is
     usually restricted to the carbonaceous de-
     mand.

   B Detection and Measurement

     When nitrification takes place during the
     BOD incubation period, its presence can
     generally be detected by the characteristic
     shape of the  BOD curve (Figure 8).  A
     significant upward swing of the curve after
     initial rate has  been established is an indi-
     cation of nitrification.

     ,To determine the extent of nitrification it
    /is necessary to measure the concentrations
    / of ammonia, nitrite nitrogen,  and nitrate
   / nitrogen which corresponds to the BOD
   t  values obtained. Suitable correction for
   i
   \ these forms  of nitrogen will yield the true
   \ carbonaceous demand.
  C Inhibition

     The carbonaceous demand can be obtained
     by preventing the nitrification process.
     Because of the nature of the organisms
     which are  involved in the nitrogen reactions,
     inhibition may be accomplished by pasteuri-
     zation of the sample at 143op or acidifi-
     cation to pH 2-3  with subsequent neutrali-
     zation.
/Ill  EFFECT OF DILUTION

  When a series of dilutions are made on a
  BOD sample usually the results vary to the
extent that only an approximate BOD value
is obtained.

A  For example,  in Table 2, 1%,  2% and 4%
   dilutions were made on a sample.  The
   4% dilution became anaerobic before the
   end of 5 days.  The 5-day BOD of the 1%
   dilution was 270 and that of the 2% dilution
   was 245.

B  Statistically one value is more reliable
   than the othe r.
       Dilution

         1%
         2%
  DO

5.5 mg/1
3.3 mg/1
2.2 mg/1
   The difference of 1% dilution is 2. 2 mg/1.
   Therefore,  2. 2 X 100  = 220 mg/1 BOD.
   The calculated BOD of 220 mg/1 is closer
   to 245 mg/1 than to 270 mg/1 BOD; there-
   fore,  the 245  mg/1 BOD is considered the
   more valid BOD for this sample.
                 Table 2
   INTERPRETATION OF BOD DATA
Sample
Initial
Final:
1% dilution
2% dilution
4% dilution
DO
8.2

5.5
3.3
0. 0
Depletion
-

2. 7
4. 9
BOD
-

270
245
Complete! - 
                                                                                          3-13

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                    USE OF BECKMAN CARBONACEOUS ANALYZER FOR
                        DETERMINING ORGANIC CARBON IN WATER

                                     Robert T.  Williams
I  INTRODUCTION

A  History of Carbon Analyses

   In the wake of a rapid population growth,
   and the increasing heavy use of our
   natural waterways,  the nation,  and indeed
   the  TO rid, is presented with the acute
   problem of increased pollutional loads on
   streams, rivers and other receiving
   bodies. This has resulted in a growing
   awareness of the need to prevent the
   pollution of streams, rivers, lakes and
   even the oceans.  Along with this aware-
   ness has developed a desire for a more
   rapid and precise method of detecting and
   measuring pollution due to organic
   materials.

B  The Methods

   In the past, two general approaches have
   been used in evaluating the degree of
   organic water pollution.

   1   The determination of the amount of
       oxygen or other oxidants required  to
       react with organic impurities.

   2   The determination of the amount of
       total carbon present in these impurities.


 C  Oxygen Demand Analyses

   The first approach is represented by
   conventional laboratory tests for determin-
   ing Chemical Oxygen Demand (COD) and
   Biochemical Oxygen Demand (BOD).  One
   of the principal disadvantages of these
   tests is that they  are limited primarily to
   historical significance,  that is, they tell
   what a treatment plant had been doing,
   since they require anywhere from  two
   hours to five  days to complete.  Since  up
   to now no faster method has been available,
   traditional BOD and COD determinations
   have become accepted standards of mea-
   sure in water pollution control work even
   though they are essentially ineffective for
   process control purposes.

   Until the introduction of the Carbonaceous
   Analyzer,  all methods taking the second
   approach,  the total carbon method of
   evaluating water  quality,  also proved too
   slow.
II   THE ANALYSIS OF CARBON

 A  Pollution Indicator

    Now the carbonaceous analyzer provides
    a means to determine the total carbon
    content of a dilute water sample in approx-
    imately two minutes.  With proper sample
    preparation to remove inorganic carbonates,
    the instrument determines the total organic
    carbon content in the sample.

 B  Relationship of Carbon Analysis to BOD
    and COD

    This quantity varies with the structure
    from 27 percent  for oxalic acid through
    40 percent for glucose to 75 percent for
    methane. The ratio of COD to mg carbon
    also varies  widely  from  0. 67 for oxalic
    acid through 2. 67 for glucose to 5. 33 for
    methane. Representative secondary  sewage
    effluents have given a ratio of COD to
    carbon content of between 2. 5 and 3. 5
    with the general  average being 3.0.

    The BOD, COD and carbon  contents of
    these and some other representative
    compounds are summarized in the follow-
    ing table.
 *Leader, Analytical Services Group, Advanced Waste Treatment Research Program, Basic and
 Applied Sciences Branch, DWS&PC,  SEC.  Reviewed December 1965.
 CH. MET. 24.4. 65
                                       9-1

-------
 Use of Beckman Carbonaceous Analyzer
Sample
Stearic Acid - C 18H36O2
Glucose - CrH, 9OR
6126
Oxalic Acid - C2H2O4
Benzoic Acid - C~H,,O0
762
Phenol - CCH.O
6 6
Potassium Acid Phthalate
KHC H O
Salicylic Acid - C-HgO,,
Secondary Effluent, Clarified
n ii "
11 n 11
5 -Day
BOD-mg/mg
. 786
. 7 3
. 14
1.38
. 05 to 2. 1 de-
pending upon
concentration

.95
1. 25
13*
23*
4*
COD-
mg/mg
2.91
1.07
.18
1.97
2.36

1. 15
1. 60
67*
36*
% Carbon
76
40
27
69
77

47
61
21*
1 2-'-
7=:=
     cln units of mg/1
III  THE CARBON ANALYZER

  A Principle of Operation

    Basically the carbonaceous analyzer  con-
    sists of three sections - a sampling and
    oxidizing system,  a Beckman Model 315
    Infrared Analyzer, and a strip-chart
    recorder.
    Carbona( coin Aniilvzer schematic
     	N	oxygen carrier from cylinder  LJcoohnp fjn
   A micro sample (20 (j.1) of the water to be
   analyzed is injected into a catalytic com-
   bustion tube which is enclosed by an elect n<-
   furnace  thermostated at 950C.  The water
   is vaporized and the carbonaceous material
   is oxidized to  carbon dioxide (CO^)  and
   steam in a carrier  stream of pine oxyivn
   The oxygen flow carries the  steam and
   CO2 out of the furnace where the  steam ih
   condensed and the  condensate removed.
   The CO2,  oxygen and remaining water \apor
   enter an infrared analyzer sensiti/.od  to
   provide  a  measure  of CO2   The output of
   the infrared analyzer is recorded on a strip
   chart, after which, the curve produced can
   be evaluated by comparing peak height with
   a calibration curve based upon standard
   solutions.  Results are obtained directl\ in
   milligrams of carbon per liter.

B  Application
          (1)
   Results     show that the method is applicable
   for most,  if not all, water-soluble organic
   compounds -- including those that contain
   sulfur, nitrogen,  and volatiles.

   Nonvolatile organic substances can be
   differentiated from volatiles, such os
   carbon dioxide or light hydrocarbons,  by
  9-2

-------
                                                     Use of Beckman Carbonaceous Analyzer
   determination of carbon both before and
   after the sample solution has been blown
   with an inert gas.  Investigators at the
   Dow Chemical Company have reported' '
   a method to be used for the determination
   of the volatile constituents of a liquid
   sample.  The method involves the use of a
   diffusion cell and sampling of both the
   contained liquid and overhead vapor.  The
   combined values can then  be related to
   the carbonaceous material originally  in
   the liquid.

C  Sample Preparation

   The Carbonaceous Analyzer is often
   referred to as a total carbon analyzer
   because it provides a measure of all the
   carbonaceous material in  a sample, both
   organic  and inorganic.  However,  if a
   measure of organic carbon alone is de-
   sired, the inorganic  carbon content of
   the sample can be removed during sample
   preparation.

   1 Removal of inorganic carbon

     The simplest procedure for  removing
     inorganic  carbon from  the sample  is
     one of acidifying and blowing.  A few
     drops of HC1 per 100 ml of sample will
     normally reduce pH to  2 or less, re-
     leasing all the inorganic carbon as CO2-
     Five  minutes of blowing with a gas free
     of CC>2 sweeps out the CC>2 formed by
     the inorganic carbon.  Only the organic
     carbon remains in the sample and  may
     be analyzed without the inorganic inter-
     ference.

   2 Volatile carbonaceous  material

     If volatile carbonaceous materials  are
     present in the  sample,  the procedure,
     using a diffusion cell, must be followed
     since light hydrocarbons  would be  lost
     in the blowing process.

   3 Dilute samples

     If the sample is dilute (less than 100
     mg/liter carbon) and is a true solution
     (no suspended particles) no further
     preparation is required.
    4  Samples containing solids

      If the sample contains solids and/or
      fibers which are to be included in the
      determination, these must be reduced
      in size so that they will be able to pass
      through the needle which  has an opening
      of 170 microns (needles having larger
      openings may be obtained if necessary).
      In most cases, mixing the sample in a
      Waring Blender will reduce the particle
      size sufficiently  for sampling.
IV  PROCEDURE FOR ANALYSIS

 A  Interferences

    Water vapor resulting from vaporization of
    the sample,  causes a slight interference in
    the method.  Most of the water is trapped
    out by the air condenser positioned immed-
    iately after the combustion furnace.  How-
    ever,  a portion of the water vapor passes
    through the system into the infrared  de-
    tector and appears on the strip chart as
    carbon.  The water blank also appears on
    the standard calibration curve, and is
    therefore removed from the final calcu-
    lation.  In tests of solutions containing the
    following anions:  NO"  Cl",  SO"2, PO^3,
    no interference was encountered with con-
    centrations up to one percent.

 B  Precision and Accuracy

    The recovery of carbon, from standard
    solutions is__98T5_: 100. 5~percent^ The
    minimum detectable  concentration using
    the prescribed operating instructions is 1
    mg/1 carbon.  Generally,  the data are
    reproducible to +  1 mg/1 with a standard
    deviation of 0. 7 mg/1 at the 100 mg/1 level.
 V  APPLICATIONS

 Several of the many research and industrial
 applications of the Carbonaceous Analyzer
 are listed below:

 A  Determine the efficiency of various waste -
    water  renovation processes,  both in the
    laboratory and in the field.
                                                                                        9-3

-------
 Use of Beckman Carbonaceous Analyzer
 B  Compare a plant's waste outlet with its
    water inlet to determine the degree of
    contamination contributed.

 C  Monitoring a waste stream to check for
    product loss.

 D  Follow the rate of utilization or organic
    nutrients by micro-organisms.

 E  To detect organic impurities in inorganic
    compounds.
VI  ADVANTAGES OF CARBON ANALYZER

 A  Speed

    The Carbonaceous Analyzer's most
    important advantage is its speed of
    analysis.  One analysis can be performed
    in 2-3 minutes.  This speed of analysis
    brings about another advantage,  economy
    of operation.  Working with dilute  samples,
    one  man can run ten to twenty carbon
    determinations per hour.  This is  probably
    more than the number of COD or BOD
    tests that can even be started, much less
    completed,  in the same period of time.

 B  Total Carbon

    Another advantage is that the measure of
    carbon is a total one.   The oxidizing
    system of the analyzer brings about com-
    plete oxidation of any form of carbon.  No
    compound has been found to which  the
    method is inapplicable.
VII CONCLUSIONS

  The Carbonaceous Analyzer provides a
  rapid and precise measurement of organic
  carbon in both liquid and air samples.  It
  should be found useful for many research
  and  industrial  applications, a few of which
  have been mentioned.

  Because of its rapidity it may be found more
  useful than the more time-consuming BOD
  and  COD measurements for monitoring
  industrial waste streams or waste treatment
  processes.
  REFERENCES

  1  Van Hall, C. E. ,  Safranko, John and
       Stenger, V. A.  Anal. Chem. 35,
       315-9.  1963.

  2  Van Hall, C. E.,  and Stenger, V. A.
       Draft of Final Report - Phase I - Con-
       tract PH 86-63-94, Analytical Research
       Toward Application of the Dow Total
       Carbon Determination Apparatus to the
       Measurement of Water Pollution.

  3  Van Hall, C. E. ,  Stenger, V.  A.
       Beckman Reprint - R6215.  Taken from
       Paper Presented at the Symposium on
       Water Renovation, Sponsored by the
       Division of Water and Waste Chemistry.
       ACS in Cincinnati.  Jan. 14-16,  1963.
 9-4

-------
                           NUTRIENTS IN WATER - THE PROBLEM
                                       Michael E. Bender*
  I  INTRODUCTION

  A  Nutrients of importance include macro-
     nutrients:  those needed in large quantities,
     and micronutrients:  those needed in
     small amounts.

  B  These nutrients  are important because
     they promote biological responses which
     interfere with some  desired use of the
     water by man.

  C  Other factors (e.g. temperature, light)
     affect the use of these  nutrients and
     should be considered in an evaluation of the
     effects of nutrients upon the aquatic
     environment.
  B  Shelford's "law" of tolerance: survival
     of an organism can be controlled by the
     quantitative  or qualitative deficiency or
     excess with  respect to any one of several
     factors which may approach the limits of
     tolerance for that organism.

  C  Qio "law":   with a temperature increase
     of 10 degrees centigrade metabolic pro-
     cesses (rates) are approximately doubled.
IV  The process of photosynthesis is the
  fixation of the sun's energy with the pro-
  duction of organic matter by plants.

  A The general reaction is given below:
 II   Algae,  bacteria, and aquatic plants are
  the forms of life v/hich nutrients affect most
  directly.

  A  Algae are  of Several Types

     1  ^Phytoplankton are small  algae suspend-
       gd in the water and form the basis of
       productivity in the aquatic environment.

     2  Benthic algae are those forms anchored
       to substrates of rock and bottom
       materials.
  B Aquatic plants are of several types.  In
    general they may be referred to as rooted
    or floating forms.


    -ES-SRend tQ organic nutrieais_intr.odu.ae,cL
    into w.ater.  A_u|Qtrnphic ba.cteria may re-
    spond and grow due to inorganic nutrient
    sources.
Ill  BIOLOGICAL LAWS

 A Liebig's "law" of the minimum: the
    essential material available in amounts
    most closely approaching the critical
    minimum needed will tend to be the limiting
                                                         C0
  B  Chlorophyll contains basically C, O, H,
     N and Mg, and in general makes up
     about 5% of the dry weight of algal cells.
  V MEASUREMENT OF PHOTOSYNTHESIS

  A Oxygen production can be used as a
    measure of photosynthesis because for
    each mole of CO2 reduced to organic
    carbon one mole of free oxygen is liberated.

    1  The value of O2/CO2 has been found
       experimentally to be  1.25 rather than
       1.0.
 B CO2 Assimilation

    1  The CO2 taken up by algae does not all
       originate from the dissolved gas.   Some
       algae  can use bicarbonate directly as
       a source of carbon.

    2  Hence measurement of CO? uptake from
       water is  a  complicated problem which
       must consider pH,
       centrations.
HCO
    3'
and CO* con-
  *Former Biologist,  DWS&PC Training Activities,

  W.RE.ntr. 2. 12.63
 SEC.  Reviewed December 1965.
                                         10-1

-------
  Nutrients in Water - The Problem
  C  Fixation of Carbon-14

     1  The use of C*4 as a tracer of C
                12
                                         in
        plant metabolism and productivity
        estimation has been widely used since
        the early nineteen fifties.
                                          14
        In this method a known amount of C
        is added to the water  and after a period
        of time the proportion of C14 in the
        plant cells to C14 added  is found.  The
        amount of carbon assimilated is then
        estimated from the following equation.
        activity of
       phytoplankton
       activity of
     C14O*  added
(K)   =
total carbon
assimilated
total carbon
available
        Where K is a constant relating to the
        slower uptake of C^4.

        The total carbon available is deter-
        mined chemically.
  D  Uptake of Mineral Nutrients

     1  The measurement of depletion of
        nutrients in solution has been tried
        but found unreliable.
  E  Chlorophyll

     1  The quantity of chlorophyll present
        has been found to bear some relation
        to productivity but not a reliable one.
VI  Nutrients of signifance in the growth and
 production of algae and plants are discussed
 below.

  A  Carbon

     1  Sources

        a  Gaseous CO_
           co
   2  Effects of the removal of carbon upon
      the water

      a Lowered pH

      b Deposition of CaCO
                           
-------
                                                            Nutrients in Water - The Problem
        be the  limiting growth factor in these
        populations.
     Inorganic micronutrients - Many elements
     are needed in very small quantities by
     algal cells.   Some of these have a known
     function in algal metabolism;  others do
     not.

     1  Mg is a cation of major importance in
        the chlorophyll molecule.
   These interferences include taste and odor,
   filter clogging, and oxygen depletion which
   may result in fish kills and subsequent
   nuisance conditions.

B  Benefits derived from productivity include
   oxygenation and hence self purification in
   polluted areas. Increased biological
   populations result from increased pro-
   ductivity and this  may lead to increased
   numbers of desirable fish species.
     2  Co is known to be necessary for vitamin  yjjj  CYCLE OF NUTRIENTS
        B
          12'
     3  Mn is necessary for several enzyme
        systems.

     4  Mo, V,  Zn, and Cu are necessary but
        these  functions are not as well known.
A  Once nutrients enter a body of water they
   are cycled through a food chain.

B  Factors affecting this food  chain (e.g.
   toxicity,  removal) will affect the concentra-
   tion and distribution of the  nutrients.
  F Organic Micronutrients

     1  Some 40% of algae investigated have
        been shown to require vitamins.  The
        following breakdown of vitamins needed
        has been established for these algae:

        a  B12       80%

        b  Thiamine  53%

        c  Biotin     10%

     2  Algae can use many organic compounds
    /   as sources of N, C and  P,  The im-
    ;v   portance of these compounds in natural
     \  waters seems small.
VII  PROBLEMS AND BENEFITS DERIVED
     FROM ALGAL PRODUCTION

  A  The major problems occur from inter-
     ference with a desired use for water.
REFERENCES

1  Lewin, Ralph A.  Physiology and Bio-
      chemistry of Algae.  Academic Press.
      1962.

2  Odum, Eugene P.  Fundamentals of
      Ecology.  W. B. Saunders Co.  1959.

3  Odum, H. T.  Primary Production in
      Flowing Waters,  Limnology and
      Oceanography.   1(2):  102-117.  April
      1956.

4  Ryther, John H.  The Measurement of
      Primary Production.  Limnology and
      Oceanography,  1(2): 72-84.  April
      1956.

5  Verduin,  Jacob.  Primary Production in
      Lakes.  Limnology and Oceanography.
      1(2):  85-91.  April 1956.
                                                                                         10-3

-------
                      SOURCES AND ANALYSIS OF ORGANIC NITROGEN
                                        F. J. Ludzack*
 I   INTRODUCTION

 A  Organic nitrogen refers to the nitrogen in
    combination with any organic radical.
    For sanitary and civil engineering the
    main interest is the nitrogen contained in
    proteins, peptides,  amines,  amino acids,
    amides and other protein compounds of
    animal or vegetable origin.  Analytical
    methods are designed to estimate these
    and may not include certain other forms
    of organic nitrogen such as nitro or nitrile
    nitrogen.

 B  Most nitrogen compounds are characterized
    by  rapid conversion from one form to
    another by biological and chemical action.
    Hydrolysis,  deamination,  peptide forma-
    tion,  and other  reactions may appreciably
    alter the  original form of sample nitrogen
    within a short time.
II   SOURCES OF ORGANIC NITROGEN

 A  Natural Origin

    1  Dead animal and plant residues

    2  Animal wastes - urea,  feces

    3  Autotrophic organisms - algae, s.bact.

    4  Heterotrophic organisms  ~f**-*-*

 B  Industrial Origin

    1  Food processing wastewater-meat,
      milk, vegetables.

    2  Pharmaceutical wastes, antibiologicals.

    3  Plastics - polyamides, nitriles.

    4  Chemical intermediates or products.

    5  Dye industry - azo,  nitro.
 Ill  ANALYSIS OF ORGANIC NITROGEN

  A  No general procedure is likely to give high
     analytical recovery on all forms of organic
     nitrogen.  Time, temperature  of digestion,
     catalyst and technique may require adjust-
     ment for optimum performance.

  B  The organic nitrogen determination  was
     designed for items listed in I. A. and their
     breakdown products.  Other forms of
     organic nitrogen may not give good yields
     by the same technique.

  C  Nature and composition of extraneous ma-
     terials affect analytical recovery.  High
     salt concentrations may  raise digestion
     temperature.  Fats and carbohydrates may
     use up acid during oxidation resulting in
     insufficient acid for nitrogen digestion.

  D  Analytical recovery should be checked for
     unusual samples to evaluate suitability of
     the test routine.

  E  McKenzie and Wallace observations  (Aust.
     Jour,  of Chem.  7. No.  1.  55-70, 1954).

     1  Digestion temperature is critical. From
        380 to 390C  usuaUy gives high analytical
        recovery on the more refractory nitrogen
        compounds of natural origin.  Nitrogen
        losses occur  above 420C.   The tem-
        perature creeps upward during digestion.

     2  The optimum temperature is associated
        with a digestion mix containing 1  g of
        potassium sulfate for each ml of  sul-
        furic acid.

   .^^^Mercury is the best catalyst but the

-------
Sources and Analysis of Organic Nitrogen
   4  Tellurium almost as good as  Hg,  no
      sulfide pptd. required.

   5  H2C>2 is the only known oxidant besides
      hot 62804 that does not tend to oxidize
      organic nitrogen to N2.  Its use is not
      recommended unless Hg cannot be used.
      It is tedious,  time consuming,  and tends
      toward low yields.

   6  About 7.3 g of H2SO4 was needed to
      oxidize  1 g of carbohydrate.  About 9 g
      for each g of fat.  Acid addition should
      allow for acid use by extraneous
      compounds.

F  Standard Methods, APHA llth Ed.

   The procedure basically is that of Morgan,
   Lackey, andGilcreas(Anal. Chem. 11,  833,
1957).  This modification was based on   "
the method of McKenzie and Wallace.
                                        \
1  The digestion mix has  0.67 g of
   potassium sulfate per ml 112804 cor-   j
   responding to a digestion temperature j
   of about 360.                        '

2  The digestion mix tends to ppt. on
   storage.  It must be diluted to hold
   the sulfate in solution at room tempera-
   ture.

3  The procedure appears effective for
   general use but the  digestion tempera-
   ture is low for refractory compounds
   unless the digestion time  is lenghtened
   which raises temperature.
 11-2

-------
                      DETERMINATION OF PHOSPHATES IN WATER

                                       J. M.  Cohen*
I  INTRODUCTION

A  Why concern about phosphates in water?

   1 Nutriait for algae which can cause taste
     and odors ancTcan inteffere"with sand
     filtration.

   2 Polyphosphates can interfere with
     chemical coagulation of water.


B  Source of Phosphates in Water

   1 Geological

   2 Agricultural fertilizers

   3 Sewage

     a  human wastes

     b  synthetic detergents

     c  biological protoplasm


   4  Industrial wastes

   5  Additive for corrosion control


II   CHEMISTRY OF POLYPHOSPHATES

 To the nonspecialist the chemistry of the
 phosphorus compounds is largely an unknown
 area.  Increased commercial use of polyphos-
 phates makes it important that chemists
 know more of the  chemistry of these materials.

 A Most common forms of phosphorus are
   . the orthophosphates derived from substi-
 / tution of the replaceable hydrogens in
   phosphoric acid (Figure  1).

 B When orthophosphates  or mixtures of
   orthophosphates are  heated, molecular
   water is withdrawn and a new class of
   phosphates are formed, called dehydrated or
   condensed phosphates.   These compounds
   belong to the  more general class of
   phosphates called polyphosphates.
Monos odium
 Dihydrogen
Orthophosphate
                                   Na3P4
Trisodium
 Ortho-
phosphate
                  Na2HP04

                 Dis odium
               Monohydrogen
             Orthophosphate
     Nomenclature for Orthophosphates

                 Figure 1
    1  A chemical definition of a crystalline
       polyphosphate is those phosphates in
       which two phosphorus atoms are linked
       through an oxygen atom as shown in
       Figure 2.
        o~~            o     o
        I                       I
    o=po   oPoPo
        o           o  o 
     Orthophosphate  Pyrophosphate

               o   o     o
                      II
           O=P OPOP=O
               o   o  o 
                Triphosphate
     Schematic Formulae of Phosphates
                  Figure 2
 ^Chemical, Basic and Applied Sciences Branch, DWSPC,  SEC.  Reviewed December 1965.

 CH. PHOS. 2a. 12.63                                                                12-1

-------
 Determination of Phosphates in Water
   2  Polyphosphates are formed by abstract-
      ing molecular water by heating mono
      and dibasic orthophosphates as shown
      in Figure 3.
 fv\
   3)  Single largest consumer of polyphos-
  '-J  phates are synthetic detergents which
      may contain 40 to 60% of a polyphos-
      phate.        "    ~

    ',,a  Practically all of the annual pro-
    i,  duction of 650, 000 tons is eventu-
        ally discharged to a natural water.

C  Polyphosphates have the property of rehy-
   drating or reverting to the orthophosphate
   forms.

   1  The rate at which such reversion oc-
      curs is important,  since the  character-
      istic behavior of  polyphosphates is lost
      as rapidly as it reverts to the ortho
      form.

   2  The rate of reversion of tripolyphos-
      phate in Ohio River water is  seen to be
      very slow, as shown in Figure 4.

   3  Other factors,  as shown in Figure 5,
      greatly influence  the reversion rate.
n(NaH,PO,) A2 " 40,C (NaPO J  +  nH?O
      t   4                     o n      ^
 Monos odium
Orthophosphate
2Na2HP04 - NaH2P04-
                             S odium
                        Trimetaphosphate
Disodium     Monosodium
  Ortho-          Ortho-
phosphate       phosphate
                                      2H2
                                 Pentas odium
                                    Tri-
                                 phosphate
         Preparation of a Polyphosphate

                 Figure 3
in OCCURRENCE OF PHOSPHATES IN WATE*R

 A  Types encountered as water contaminant

    1  Orthophosphate

       Source can be fertilizer, endproductof
       polyphosphate reversion, an industrial
       waste and geological.

    2  Polyphosphate

       Source can be synthetic detergents,
       water conditioning and,  to a lesser ex-
       tent, certain biological compounds.

    3  Biological Protoplasm

       Phosphorus which has been incorpo-
       rated in organisms during metabolism.

    4  Organic Phosphate

       Small amounts originate from human
       wastes, from decomposed biological
       fauna and industrial wastes.

 B  Types of Phosphate Analysis

    The above types of phosphates can be de-
    termined in a water  sample in the  follow-
    ing manner.

    1  Total phosphates

       This analysis will yield all forms of
       phosphate and will include:

       a ortho

       b poly

       c biological

       d organic

    2  Total soluble phosphate

       Analysis performed on filtered sample
       will include:

       a soluble ortho

       b soluble poly
 12-2

-------
                                                Determination of Phosphates in Water
10
                                   Figure 4
            20
                       40
  60 '  '      180
Elapsed Time - days
                                                        200
                                                                    220
                                                                              240'
                  TRIPOLYPHOSPHATE REVERSION IN OHIO R. WATER
Factor
Approximate Effect on Rate
  Temperature

  PH

  Enzymes

  Colloidal Gels

  Complexing Cations

  Concentration

  Ionic Environment in
        the Solution
      105 - 106 Faster from Freezing to Boiling

      103 - 104 Slower from Strong Acid to Base

      As much as 105  - 10B Faster

      As much as 104  - 105 Faster

      Several Times Faster

      Roughly Proportional


      Severalfold Change
                   Major Factors Affecting the Rate at Which
           Chain and Ring Phosphates Undergo Hydrolytic Degradation

                                   Figure 5

-------
  Determination of Phosphates in Water
        c  soluble organic

      3  Ortho phosphate

        This is the most common determination
        and will theoretically determine only
        this form to the exclusion of all others.


  IV ANALYTICAL  PROCEDURES

   A  Procedures most applicable to water
      analysis are colorimetric methods whose
      basic reactions are as follows:

      1  Formation of phosphomolybdic com-
        pound by adding ammonium molybdate
        to form a yellow colored heteropoly
        acid.

      2  Reduction of the heteropoly acid with
        some reductant, for example, stannous
        chloride.

      3  Measurement of the intensity of the
        blue color and comparing with a standard
        curve.

   B  Orthophosphates are determined by apply-
      ing the above procedure.

   C  Polyphosphates are determined by analyz-
      ing for orthophosphate before and after
      acid hydrolysis:
   ortho (after hydrolysis)  - ortho (before hy-
   drolysis) = Polyphosphate  (as
4
D  Total phosphates are determined by wet-
   digesting the sample to convert all forms
   to the ortho for which an analysis is then
   made.
   V VARIABLES IN ORTHOPHOSPHATE
     ANALYSIS

   A Ratio of acid to molybdate must be main-
     tained constant at the optimum.
                                                 B Amount of molybdate reagent is not criti-
                                                   cal, so long as the final acidity is about
                                                   0. 2 - 0. 4 N sulfuric acid.

                                                 C Amount of reductant is also not critical,
                                                   although too much reagent  can  lead to tur-
                                                   bidity on standing.

                                                 D Time for  color development must be
                                                   closely controlled for both the  standard
                                                   and sample.

                                                 E Temperature produces about a 1% in-
                                                   crease in color for each 1C rise.

                                                 F Interferences

                                                   1  These ions must be absent - silver,
                                                      arsenate, barium, dichromate, mer-
                                                      curic,  mercurous, molybdate, lead,
                                                      chlorostannate, zirconium,  tungstate,
                                                      silicate and nitrite.

                                                   2  Other ions interfere  but can be present
                                                      in varying concentrations before intro-
                                                      ducing an error greater than 2%.
VI RECENT MODIFICATION IN ANALYTICAL
   PROCEDURE^)

 A Modification avoids these two weaknesses
    of the above method.

    1 Partial hydrolysis of the polyphosphates
      because of the acid conditions of the
      test.

    2 Interfering substances in natural waters.

    3 Turbidity must be removed.

 B Modification consists of extracting the re-
    action product of phosphate and molybdate
    with a 1 + 1 mixture of benzene and iso-
    butanol.  Reduction of the heteropoly acid
    is performed in the organic layer.


VII RESULTS AND SENSITIVITY

 A In water analysis results are generally
    expressed as PO4 although other expres-
    sions, such as P or ?2O5, may be used.
   12-4

-------
                                                       Determination of Phosphates in Water
B  Colorimetric methods are highly sensitive
   and will detect down to 0. 002 ppm.

C  In the range of 0.2 - 1.0 ppm a precision
   of  +  10% can be obtained.
REFERENCES

1  Moss,  H. V.  (Chairman,  AASGP Com-
      mittee)  "Determination of Orthophos-
      phate, Hydrolyzable Phosphate and
      Total Phosphate in Surface Waters".
      JAWWA, _50:1563.  December 1958.

2  Quimby, Oscar T.  "The Chemistry of
      Sodium Phosphate".  Chemical Reviews,
      50:141.  February 1947.

 3  Standard Methods for the Examination of
      Water and Wastewater,  llth Edition,
      APHA, AWWA,  WPCF.  1961.
                                                                                      12-5

-------
                  DETERMINATION OF ORTHO AND POLYPHOSPHATE BY
                    MOLYBDENUM BLUE-STANNOUS CHLORIDE METHOD
                                        R. J. Lishka*
 I  COLLECTION OF SAMPLE

 Collect sample in the prescribed manner and
 analyze as soon as possible to minimize con-
 version of polyphosphate to orthophosphate.
 II  APPARATUS

 Spectrophotometer or filter photometer,
 use at 690 millimicrons.
for
   Add  155 ml of cone. H2SO4 slowly to
   400 ml of distilled water and cool.

   Add the molybdate solution to the sulfuric
   acid solution (never in reverse) and
   dilute to 1.0  liter.

E  Stannous chloride solution - Dissolve 2.5
   gms of fresh SnClg' 2H2O in 100 ml of
   reagent grade glycerine.  Heat in water
   bath and stir to dissolve.
Ill  REAGENTS

 A Phenolphthalein indicator - Dissolve 2.5
    gms of phenolphthalein powder in 250 ml
    of ethyl alcohol,  add 250 ml of distilled
    water, then add 0. 020N NaOH dropwise
    to a faint pink color.

 B Sulfuric acid -Add 310 ml of cone.  H2SO4
    slowly to about 600 ml of distilled water.
    Cool to room temperature  and dilute to
    1.0 liter.
         IV  PROCEDURE

          Preliminary Cleaning of Glassware.   Because
          laboratory detergents contain phosphate which
          cannot be easily rinsed off, a preliminary
          treatment with phosphate reagents is necessary
          to remove  that adsorbed on the glass sur-
          faces.  After the glassware has been properly
          cleaned it should be reserved for this test only.

          A Clean and thoroughly rinse all glassware
             in the usual manner.
 C Standard Phosphate

    1  Stock standard phosphate solution
       (0. 50 mg PO4 per ml).  Dry a portion
       of reagent grade potassium dihydrogen
       phosphate overnight at 103C before
       use.  Dissolve 0.7164 gms of the
       KH2PO4 in distilled water  and make up
       to 1.0 liter.

    2  Working standard phosphate  solution
       (0.005mg/PO4 per ml).  Dilute  10.0
       ml of the stock standard phosphate to
       1. 0 liter with distilled water.  Protect
       this solution from the light and make
       up fresh each month.
          B  Before use, treat each container which
             will come in contact with the sample as
             follows:
             1  Fill each container with distilled water
                and add 2. 0 ml of ammonium molybdate
                solution, reagent III. D, and mix.

             2  Add 1 ml of sulfuric acid solution,
                reagent III. B, and 1 ml of Stannous
                chloride solution,  reagent III. E.  Mix
                thoroughly and allow to stand for 10-
                15 minutes.  Make certain that all
                internal surfaces of the containing
                vessels come in contact with the reaction
                mixture.  Discard the  reaction mixture
                and rinse each container with distilled
                water.
 D  Ammonium molybdate solution - Dissolve
    25.0 gms of (NH4)6Mo7O24-4H2O in 175
    ml of distilled water.
          Once this cleaning procedure has been per-
          formed the glassware  can be reused without
          repeating the treatment unless it has been
          cleaned with detergent.
 *Chemist,  Analytical Reference Service, Training Program, SEC.  Reviewed December  1965.

 CH. PHOS.lab. 1. 12. 63                                                                   r>-(j

-------
 Determination of Phosphate (Ortho and Poly)
   Preparation of Standards (Photometric
   Procedure) Observe room temperature.
   Standards  and samples must be run at
   same temperature,
   results.
+ 2 C, for reproducible
      Add increasing volumes of working
      standard phosphate reagent III. C. 2 to
      several vessels (previously cleaned
      according to IV. B).  Add  1. 0 ml of
      sulfuric acid,  reagent III. B.  Make up
      to 50. 0 ml with distilled water.

      The following table is  suggested  as
      a convenient series for use with  a
      photometer.
ml of soln
III. C.2
0 (Blank)
0.5
1.0
2.0
5.0
10.0
mg PO4/50 ml
0
.0025
.0050
.0100
.0250
.0500
P04, mg/1
0 (Blank)
.05
0. 10
0.20
0.50
1.00
D  Raw Water Sample (Photometric
   Procedure)

   1  Filter at least 200 ml of the sample to
      remove  turbidity.

   2  Place 100 ml of the filtered sample
      containing not more than 0. 050 mg PC>4
      or  an aliquot diluted to 100 ml in a
      250 ml Erlenmeyer flask.  Place several
      glass beads  or boiling stones in the flask.

   3  Omit this step if the pH is below 8.2.
      Otherwise

      a  add  two drops of phenolphthalein,
         reagent III. A

      b  add sulfuric acid solution, reagent
         III. B, dropwise, to discharge the
         pink color.

   4  Add exactly  2.0 ml of sulfuric acid,
      reagent  III. B, and boil gently for one-
      half hour. Add a small amount of
    distilled water if volume drops below
    25 ml during the boiling period.

 5  Cool,  make  up to 100 ml with distilled
    water and adjust to temperature of
    standard curve.  Place 50  ml in a
    vessel (previously cleaned according to
    step IV. B) and label Total Phosphate.

 6  Place 25 ml, or an aliquot diluted to
    25 ml, of the filtered sample from step
    IV. D. 1 in a  vessel (previously cleaned
    according to step  IV. B)  and add 1. 0 ml
    sulfuric acid, reagent III. B.  Make up
    to 50.0 ml with distilled  water and label
    Orthophosphate.

 7  Add 2.0 ml of ammonium molybdate,
    reagent  III. D,  to each sample and
    standard.  Mix thoroughly.

 8  Add 5 drops (0.25ml) of stannous chloride
    solution, reagent III. E.  Mix well and
    allow  to stand for 20 (+5) minutes.

 9  Read in  spectrophotometer at 690 m|J..
    Use the  0 standard to zero the instrument

10  Prepare calibration  curve.
                           E  Calculation
                                mgPO /I =  mg P4 X
                             1000
                                                  ml sample


                           mg polyphosphate/1  mg total phosphate/I -

                                                  mg Orthophosphate/I


                           V NOTES

                           A The concentration of acid in the sample and
                             standards has a direct effect on the amount
                             of color produced.  It is,  therefore, im-
                             portant that addition of reagent III. B be
                             performed accurately.

                           B The phosphomolybdate blue produced by
                            ^ the reaction is not stable and tends to
                             fade gradually after about 20 minutes.  Most
                             accurate results are obtained when time
                             requirements are observed.
  12-7

-------
                                                Determination of Phosphate (Ortho and Poly)
C  Temperature is another variable which
   affects the color formation.  Samples and
   standards may be adjusted to room tem-
   perature after boiling by allowing to
   stand for several hours before addition of
   reagents III. D and III. E.

D  If the phosphate concentration in the
   sample is completely unknown,  several
   dilutions of the sample may be run simul-
   taneously and that aliquot used for final
   reading which falls near the middle of the
   standard series.

E  Scrupulous care should be observed in
   cleaning of the  glassware prior to use. If
color appears in the blank, or a particular
standard appears out of line,  phosphate
contamination is probably  responsible.

The working standard phosphate  solution,
reagent III. C. 2, should be kept in the
dark to prevent reduction of phosphate
concentration through algal growth.

In preparing reagent III. D, the molybdate
must  be added to the sulfuric acid,  never
the reverse.  Reversing the addition
precipitates  some of the molybdate,  which
is then very  difficult to dissolve.
                                                                                      12-f

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                            AMMONIA,  NITRITES AND NITRATES

                                    Betty Ann Punghorst*
I  SOURCES AND SIGNIFICANCE OF
   AMMONIA,  NITRITES AND NITRATES
   IN WATER

The  natural occurrence of nitrogen compounds
is best demonstrated by the nitrogen cycle
( Figure  1) .

A  Ammonia

   1  Occurrence

      Ammonia is a product of the micro-
      biological decay of animal and plant
      protein.  In turn it can be used directly
      to produce plant protein.  Many fertili-
      zers contain ammonia.

   2  Significance

      The presence  of ammonia nitrogen in
      raw surface waters might indicate do-
      mestic pollution.  Its presence in waters
      used for  drinking purposes may require
      the addition of large amounts of chlorine
      in order  to produce a free chlorine
      residual. The chlorine  will first react  , 
      with ammonia to form chloramines be-  \t
    ___for it exe*rts"Tts full pacferojidjij..effects i ''
      (free chlorine residual).               '

B  Nitrite

   1  Occurrence

      Nitrite nitrogen  occurs in  water  as an
      intermediate stage in the biological de-
      composition of organic nitrogen.  Nitrite
      formers  ( nitrosomonas) convert ammonia
      under aerobic  conditions to nitrites.  The
      bacterial reduction of nitrates can also
      produce nitrites under anaerobic condi-
      tions.  Nitrite is used as a corrosion
       of larg e quantities indie at e s a source
                                ~~
   2  Significance
      Nitrites are usually not found in_ surface
      water to a^fe'aT'exfe'nT.  The presence
 C  Nitrate

    1  Occurrence

       Nitrate formers convert nitrites under
       aerobic conditions to nitrates (nitro-
       bacter).  During electrical storms,
       large amounts of nitrogen ( N%) are
       oxidized to form nitrates.  Finally,
       nitrates can be found in fertilizers.

    2  Significance

       Nitrates in waters usually indicate the
       final stages of biological stablization.
       Nitrate rich effluents discharging into
       receiving_waters ?an^_under_j)roper en-
       vironment conditions cause stressj^p
       stream quality by groducingjilgal
       blooms.  Drinking waters containing
       excessive amounts of nitrates can
       causeinfant niethemoglobinemia.
II   ANALYSIS OF AMMONIA,  NITRITES,
    AND NITRATES IN WATER

 A  Sample Collection

    If a sample cannot be analyzed promptly,
    several procedures may be followed in
    order to preserve the sample.

    1   Freezing will retard biological activity.

    2   The addition of 1 ml of chloroform/100
       ml sample should retard biological
       activity.

    3   The addition of 0. 8 ml cone H2SO4/1
       liter of sample will also maintain the
       nitrogen balance.   However,  it is
       essential that the  sample be neutralized
       before proceeding with the  analysis.
*Chemist,  DWS&PC Training Activities, SEC.  Reviewed December 1965.
CH.N.6. 11.64
                                    13-1

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Ammonia, Nitrites and Nitrates
                                        rterial Oxidatign)
                                    Figure  1
                                    The  Nitrogen Cycle
  13-2

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                                                          Ammonia, Nitrites and Nitrates
B  Determination of Ammonia

   1  Nesslerization

      a Reaction

        Nessler's  reagent, a strong alkaline
        solution of potassium mercuric iodide,
        combines with NHg in alkaline solu-
        tion to form  a yellowish brown
        colloidal dispersion.
                                   3KOH
   The intensity of the color follows the
   Beer-Lambert Law and exhibits
   maximum absorption  at 425 m(i.

b  Interferences

   1  Nessler's reagent  forms a pre-
      cipitate with some ions (e.g.,
      Ca++, Mg++, Fe+++,  and S=).
      These ions can be  eliminated  in
      a pretreatment flocculation step
      with zinc sulfate and alkali.  Also
      EDTA or Rochelle  salt solution
      prevents precipitation with Ca^+
      or  Mg++.

   2   Residual chlorine indicates that
      ammonia may be present in the
      form of chloramines.  The ad-
      dition of sodium thiosulfate will
      convert  these chloramines to
      ammonia.

   3   Certain  organics may produce an
      off  color with Nessler's reagent.
      If these  compounds are not steam
      distillable,  the interference may
      be eliminated in the distillation
      method.

   4   If the turbidity and  natural color
      of the sample cannot be eliminated
      with flocculation, it is then neces-
      sary to use  the following distilla-
     tion method.
O     + 7KI   + 2H.O
                   It
                                                  Yellow-Brown C.~~




                                                     2  Distillation

                                                       a  Reaction
                                                          1) The sample is distilled in the
                                                             presence of a phosphate buffer
                                                             at pH 7.2 - 7.4.
   NH
                                                                               +  H
                                                     H  -t- NaHPO.
                                                        Buffer
NaH0PO.
    Li   Q
                         Na
             pHmaintained be-
             tween 7.2 -  7. 4
                                                          2)  The ammonia in the distillate is
                                                             then measured  by either of two
                                                             techniques.

                                                             a)  Nesslerization is used for
                                                                samples containing less than
                                                                1 mg/ 1 of  ammonia nitrogen.

                                                             b)  Absorption of NHq by boric
                                                                acid and back titration with a
                                                                standard strong  acid, is more
                                                                suitable for  samples contain-
                                                                ing greater than 1 mg/1 of
                                                                NH N.
                                                                   iJ
                                                                                       13-3

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Ammonia,  Nitrites and Nitrates
   NH   +   HBO -
      ..
                                                     3  Precision

                                                        On a synthetic sample containing 0.25
                                                        mg/1 of nitrite nitrogen, the Analytical
                                                        Reference Service (Water  Minerals
                                                        Study,  1961)  reported 125  results with
                                                        a standard deviation of + 0. 029 mg/1.

                                                  D Determination of Nitrate

                                                     1  Phenoldisulfonic acid

                                                        a  Reaction

                                                           1)  Phenoldisulfonic acid reacts with
                                                              nitrate to  produce a  nitro
                                                              derivative.
                                                   HSO,
                                                                                  OH
                                                                            HSO
                                                                + H + NO
13-4

-------
                                                             Ammonia.  Nitrites and Nitrates
      In alkaline solution the nitro derivative
      rearranges to form a yellow-colored
      compound which exhibits maximum ab-
      sorption at  410 m|A.
        OH
HSO
             NO
                    KSOr
             + 3KOH-
       S03H

   COLORLESS
      b  Interferences
                                      O
                                     =N	OK
                           S03K

                          YELLOW
         1) Chloride ion under the acid con-
           ditions of the test introduces a
           negative interference.
6 Cl  + 2NO0 +
                                   2NOt+ 4H0O
                                            
      Silver sulfate can be used to pre-
      cipitate Cl" but due to incomplete
      precipitation of Ag+, an off color
      or turbidity is produced when the
      final color is developed.

   2)  Nitrites in concentrations greater
      than 0.2 mg/1 N introduce  posi-
      tive interference.  However, in
      most waters the concentration of
      nitrite  is insignificant as compared
      to nitrate.

   3)  Color and turbidity may be re-
      moved  by using Al (OH) 3 suspen-
      sion or by flocculation with ZnSO.
      and alkali.

c  Precision   vx-t, *  & ^-^  '

   On a synthetic sample containing 1. 1
   mg/1 of nitrate N,  the ARS Water
   Minerals Study (1961) reported 118
   results with a standard deviation of
   + 1. 119 mg/1.
                                                     2  Brucine
   a  Reaction

      Brucine, a strychnine compound,
      reacts with nitrate to form a yellow
      compound which exhibits maximum
      absorption at 410 mji.  The reaction
      according to the procedure as out-
      lined in Standard Methods (p.  178)
      does not follow Beer's Law.  How-
      ever,  a recent modification by
      Jenkins et al. (see reference 2) has
      been developed.   Conditions are con-
      trolled in the reaction so that Beer's
      Law is followed  and concentrations
      below 1 mg/1 nitrate nitrogen can
      be determined.

   b  Interferences

      1)  Nitrite  may react the same as
         nitrate  but can be eliminated by
         the addition of sulfanilic acid to
         the brucine reagent.

      2)  Organic nitrogen compounds may
         hydrolyze and give positive inter-
         ference at low (less than 1 mg/1)
         nitrate  nitrogen concentrations.

      3)  Residual chlorine may be elimi-
         nated by the  addition of sodium
         arsenite.

   c  Precision
                                         u
      1)  On a synthetic sample containing
         1. 1 mg/1 of nitrate N, the ARS
         Water Minerals Study (1961) re-
         ported 21 results  with a standard
         deviation of + 0. 490 mg/1.

      2)  Jenkins, et al. report a standard
         deviation of + 0. 0048 mg/1 on a
         sample with  a mean nitrate
         nitrogen concentration of 0.287
         mg/1.
3  Hydrazine reduction /,
                                                                            , V-
                                                                                 '~ *V 2
                                                       A method using hydrazine to reduce
                                                       nitrate to nitrite followed by subsequent
                                                                                       13-5

-------
Ammonia,  Nitrites and Nitrates
      measurement of nitrite by diazotization
      was recently reported by Fishman, et al.
      (see reference 1).  The procedure has
      been successfully adapted to the Auto
      Analyzer where a high degree of control
      of reaction conditions can be achieved,
      (see reference 3).
REFERENCES

1  Fishman,  Marvin J.,  Skougstad,  Marvin
      W., and Scarbio, George Jr.  Diazoti-
      zation Method for Nitrate and Nitrite.
      JAWWA. 56:633-638.  May 1960.
2  Jenkins, David and Medsker, Lloyd L.
      Brucine Method for Determination of
      Nitrate in Ocean,  Estuarine,  and  Fresh
      Waters.  Anal. Chem.  36:610-612.
      March  1964.

3  Kamphake, L. J. Chemist,  Engineering
      Section, Basic and Applied Sciences
      Branch, DWS&PC, Robert A. Taft
      Sanitary Engineering Center.  Personal
      Communication.

4  Sawyer, Clair N. Chemistry for Sanitary
      Engineers. McGraw-Hill Book Company,
      Inc.  New York.  1960.

5  Standard Methods for the Examination of
      Water and Wastewater. APHA, AWWA,
      WPCF.   1960.
        Vs
             -J
13-6

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                 AMMONIA DETERMINATION BY DIRECT NESSLERIZATION

                                        R. J. Lishka*
 A  REAGENTS
    1  Nessler reagent:

       Dissolve 100 g  mercuric iodide and
   \j  70 g. potassium iodide in a small
     '  quantity of ammonia-free water and
     I  add to a cool solution of  160 g. sodium
     \hydroxide in 500 ml ammonia-free
       water.   Dilute to 1 liter with ammonia-
       free water.

    2  Stock ammonium chloride solution:

       Dissolve 3. 819 g anhydrous ammonium
       chloride in ammonia-free water and
       dilute to 1 liter.

          1. 00 ml   =   1. 00 mg N

    3  Standard ammonium chloride solution:

       Dilute 10 ml of  stock ammonium
       chloride solution to 1 liter with
       ammonia-free water.

          1. 00  ml  =  0.0100 mg N

    4  Zinc sulfate solution:

       Dissolve 100 g  ZnSO4   7 H2O in
       ammonia-free water and dilute to  1
       liter.

    5  Sodium hydroxide solution:

       Dissolve 240 g  NaOH in 500 ml of
       ammonia-free water and dilute to  1
       liter.

    6  Rochelle salt solution:

       Dissolve 50  g  K NaC4H4Og- 4 H2O
       in 100 ml ammonia-free  water.  Boil
      off 30 ml of the solution-'to remove
      any ammonia present in the salt. After
      cooling,  dilute to 100 ml.

 B PROCEDURE
      Add 1 ml zinc sulfate solution to 100
      ml of sample; mix thoroughly; add
      0. 5 ml hydroxide  solution; again mix
      thoroughly.

      After precipitate has settled, filter
      the sample through Whatman No.  1
      paper and discard the first 25 ml of
      the filtrate.

      Take 50. 0 ml,  or an aliquot diluted to
      50. 0 ml with ammonia-free  water,
      add 2 drops of Rochelle salt solution,
      and mix well.

      Prepare a series  of standards con-
      taining 0. 0, 0.5,  1.0,  and 3. Oml of
      standard ammonium chloride solution.
      Dilute each to 50 ml with ammonia -
      free water.

      Add 1 ml Nessler  reagent to each
      standard and sample and mix well.

      After 10 minutes,   measure the ab-
      sorbance in a spectrophotometer at
      425 m|jL,  using 1 cm.  cells.  Use the
      0. 0 standard as a reference.

      Plot the  standard  curve and  determine
      the mg of N in the  sample.
 C CALCULATION:

                    mg ammonia N X 1000
mg/1 ammonia N =  l sample nesslerized
*Chemist,  Analytical Reference Service, Training Program,  SEC.  Reviewed December 1965.

CH.N.Iab. 1. 12. 63                                                                     13-7

-------
Ammonia  Determination by Direct Nesslerization
                       AMMONIA DETERMINATION DATA SHEET
                                     Absorbance                      ^TTT ,
                                                                  mgNH_/N
                                 	reading	               6    3	
       0.5 ml standard soln.       	                0.005
       1.0 ml standard soln.	                0.010
       3.0 ml standard soln.	                0.030
       5.0 ml standard soln.       	                0.050
      10.0 ml standard soln.	                0.100
      50  ml sample             	       	                	
       mg NH3/N in 50 mix 20 =	    mg NHg/N per liter
13-8

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                         LABORATORY PROCEDURE FOR NITRATE
                               MODIFIED BRUCINE METHOD
                                    Betty Ann Punghorst*
 I   REAGENTS

 A  Stock standard nitrate (100 mg/1 N)  0.7218
    gm KN03/1.

 B  Working standard (1 ml = 0. 001 mg N).
    Dilute 10 ml of stock to 1 liter.

 C  30% NaCl solution.

 D  Sulfuric acid solution

    Add 500 ml cone. H SO  to 125 ml HO.

    Cool and keep tightly stoppered.

 E  Brucine - sulfanilic acid reagent

    Dissolve  1 gm  brucine sulfate _and_ 0. 1 gm
                                                                               ' I.-
    of

        3 ml of cone. HC1.  Cool.  Make up
   to 100 ml.  Solution is stable for^several
   months.
II  PROCEDURE

 A Preparation of Standards and Samples

   1  Standards

      Pipette 1.0, 2.0, 5.0, 7.0, and 10.0
      ml of working standard into 1" colori-
      metric tubes,  held in a suitable rack
      in a cold water bath.  Make up to 10 ml
      with distilled water.

   2  Samples

      Pipet 10 ml of sample (0. 5 - 8. 0 jig N)
      into a 1" colorimetric tube.  Run dupli-
      cate analyses on each sample.

 B Addition of 30% Sodium Chloride

   Add 2 ml of 30% NaCl to each tube (Use
   volumetric pipette).  Mix well by swirling.
               NOTES
1" colorimetric tubes should be matched.
Beer's Law is followed up to 10 ^g
NO,N.
   O
                     ~> \
                    a
 *Chemist, DWS&PC Training Activities,  SEC.  Reviewed December 1965.

 CH. N.lab.2a. 12.65
                                  13-9

-------
Lab. Procedure for Nitrate Modified Brucine Method
   Allow contents of tubes to reach tempera-
   ture of cold water bath.

C  Addition of Sulfuric Acid Solution

   Pipet  10 ml of tL^SO^ solution into each
   tube.  (Use volumetric pipette)  Mix well
   by swirling.  Allow contents to reach
   thermal equilibrium in cold water bath.

D  Color Development

   1  Add 0. 5 ml of brucine-sulfanilic acid
      solution and mix thoroughly.

   2  Place tubes in boiling water bath for
      20  minutes.

   3  Remove tubes from boiling water bath
      and immerse  them in a cold water bath
      and bring temperature to between  15-
      25C.

   4  Adjust Spectronic 20 (410 m|i) to 100%
      TRANSMITTANCE using distilled water
      as  a blank. Read and record % TRANS-
      MITTANCE data for  samples and
      standards.

E  Calculations

   1  Plot % TRANSMITTANCE vs standard
      concentration on semi-log paper.

   2  Calculate concentration of nitrate
      nitrogen in 10 ml aliquot of sample from
      the standard curve.

   3  Calculate mg/1 of nitrate nitrogen in
      sample.  MGNO3N in 10 ml aliquot X 100 -
      mg/1 NO3N.

REFERENCES
            NOTES
It is essential for good color development
that the samples and standards be mixed
well.
It is essential that the tubes be cooled
(15 - 25C) before adding the brucine sul-
fanilic acid reagent.  The color develop-
ment depends upon controlled temperature
conditions.

When samples have visible turbidity and
color,  it is necessary to use the following
procedure.  Before reading % transmit-
tance of the samples, adjust the Spectronic
20 to 100% transmittance  using a sample
blank.  The sample blank, containing all
reagents except the brucine - sulfanilic
acid solution, can be prepared while the
samples  are  in the boiling water bath.

The  color developed  is stable for 30
minutes.
   Finger, James H.  Nitrate Determination in
      Saline and Estuarine Waters: Comparison
      of Hydrazine Reduction and Brucine
      Modification Methods.  Laboratory In-
      vestigations Report No. 3.  TA&I Section.
      Robert A. Taft Sanitary Engineering
      Center.  Cincinnati, Ohio. October,  1964.
Jenkins, David and Medsker,  Lloyd L.
   Brucine Method for the Determination
   of Nitrate in Ocean,  Estuarine and
   Fresh Waters.   Anal.  Chem.  36:610-
   612.  March,  1964.
13-10

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            DETERMINATION OF CHLORIDE AND SULFATE IN WATER SUPPLIES

                                       D. G. Ballinger*


                                          CHLORIDE
 I  OCCURRENCE

 In fresh waters,  high coloride values may
 indicate the presence of animal pollution.
 However, the chloride test as an indication
 of animal pollution should be  confirmed by
 bacteriological and sanitary analyses. A
 high chloride value can be due to other sources
 such as oil field brines and other industrial
 wastes; also from the passage of water through
 a natural salt formation;  or from agricultural
 return  wastes.
B  Mohr

   The neutral or weakly alkaline sample is
   treated with chromate indicator and
   titrated with silver nitrate.  Silver chloride
   precipitates and at the endpoint,  red silver
   chromate is formed.  Iodide and bromide
   register as equivalent chloride.  Phosphate,
   sulfide and cyanide interfere.  Sulfite inter-
   feres but can be removed with hydrogen
   peroxide.  Color, if present,  can be re-
   moved with aluminum hydroxide suspension.
 II  SIGNIFICANCE

 Chloride compounds may break down,
 especially under boiler pressures, to form
 HC1 thus causing corrosion problems.
 Chlorides are undesirable in ice making,  as
 they spoil the appearance of the ice.  Approxi-
 mately 500 mg/1 salt imparts an undesirable
 taste to drinking water.  For brewing or soft
 drinks, the salt content should not exceed
 275 mg/1 as the concentration may be in-
 creased in the process.  The U.S. Public
 Health Service Drinking Water Standards for
 potable waters recommend a maximum chloride
 content of 250 mg/1,  because of taste effects.
Ill  ANALYTICAL METHODS

 A Volhard

    An excess  of silver nitrate is added to the
    acidified sample to precipitate chlorides.
    The excess silver is titrated with thio-
    cyanate in  presence of ferric ion and
    nitrobenzene. At the endpoint,  red ferric
    thiocyanate is formed.  Iodide  and bromide
    register as equivalent chloride.  Phosphate
    and sulfite do not interfere, but sulfide
    does.
C  Mercuric Nitrate

   The sample,  adjusted to pH 3. 1*,  is
   titrated with mercuric nitrate solution.
   Since  slightly dissociated mercuric chloride
   is formed,  no precipitation occurs.  At the
   endpoint, the excess mercuric ions produce
   a violet color with diphenylcarbazone in-
   dicator.  Bromphenol blue is added to the
   indicator solution for pH adjustment.  It
   improves the sharpness of the endpoint by
   masking the pale color produced by di-
   phenylcarbazone during the titration.

   Iodide and bromide register as equivalent
   chloride.  Sulfite in concentrations greater
   than 10 mg/1 interferes but can be removed
   with hydrogen peroxide.   Chromate and
   ferric ions interfere when in excess of
   10 mg/1.
*Do not use hydrochloric acid to adjust pH
in this determination.
  *In Charge,  Chemistry, Technical Advisory and Investigations Section,  DWSPC,  SEC.
  Reviewed December 1965.
  CH.HAL. cl. 6c. 11.64
                                                                                        14-1

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  Chloride
IV  PRECISION                                     REFERENCES

  The Analytical Reference Service Mineral           l  Standard Methods for the Examination of
  Study of 1961 reported on a reference sample             Water and Wastewater.  llth Edition.
  containing 241 mg/1 Cl".  Forty-two labora-             APHA,  AWWA, WPCF.  1960.
  tories employed the Mohr titration procedure,
  with a standard deviation of + 10 mg/1.  Nine        2  Water Mineral Study of 1961.  Analytical
  laboratories used the  Mercuric Nitrate method            Reference Service, SEC.
  and  obtained slightly better results  with a
  standard deviation of +_ 7. 8 mg/1.'^'
  14-2

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                                          SULFATE
                                       D. G. Ballinger*
 I   DEFINITION AND OCCURRENCE

 Sulfate is found in all fresh waters as a
 result of solvent action of water on gypsum
 (CaSO4' 2H2O) and other common minerals
 such as Epsom salt (MgSO4- 7H2O).  Sulfates
 also occur  as the final oxidized stage of
 sulfides, sulfites, and thiosulfates.  They may
 also occur  as the oxidized state of organic
 matter in the sulfur  cycle,  and, in turn serve
 as sources of energy for sulfate-reducing
 bacteria; at lower pH these  will form hydro-
 gen sulfide, which is quite  undesirable.
 Indusrial ,
 pulp miiJ^a^nneries, ^fiifiklijJg .operations
"aHToth^r plants that use^sulfates^pr^sulfuric,
 acul, contribute to the natural sulfate content
 of_rawjwatejs-   Sulfuric acid is the heaviest
 tonnage chernicalrnanufacTuT'e'S.  ""
II   SIGNIFICANCE

 PHS drinking water standards call for not
 more than 250 mg/1 of SO4.  Public water
 supplies with high sulfate content are com-
 monly used with no adverse effects, and this
 limit does not appear to be based on tests or
 physiological effects other than a laxative
 action for new users.  The taste threshold of
 magnesium fulfate is  400  - 600 mg/1, and
 for calcium sulfate is reported to be 250 -
 900 mg/1. Excessive concentrations (1000  -
 2000 mg/1) of magnesium sulfate may have
 purgative effects.

 Sulfates may  be either beneficial or detri-
 mental in water used  for manufacturing.  In
 the brewing industry, the presence of sulfate
 is advantageous, as it aids in producing
 desirable flavor.  On the other hand,  Sulfates
 are undesirable in the ice industry because
 of the formation of white butts.  In domestic
 water systems,  Sulfates  do not appear to
 cause any increased  corrosion on brass fit-
 tings,  but concentrations above 200 mg/1 do
 increase the amount of lead dissolved from
 lead pipes.
  Calcium sulfate scale is normally not en-
  countered in once-through cooling water
  systems since it is quite soluble at the
  temperatures usually existing. Inrecircula-
  ting systems, where concentration takes
  place, the sulfate content of the circulating
  water may become high enough to precipitate
  calcium sulfate in  the form of gypsum
  (CaSO4-2H2O).

  Treatment measures for preventing  scale
  formation are directed primarily at  calcium
  carbonate precipitation since it is less
  soluble than the sulfate.  The  usual treat-
  ment uses sulfuric acid which increases the
  sulfate content.  This, under certain
  conditions may create the additional problem
  of calcium sulfate  scale formation.

  The precipitation of calcium sulfate  can be
  hindered by surface active agents such  as the
  polyphosphates and organics.  If necessary,
  sulfates can be removed by evaporation, de-
  mineralization, or precipitation with barium
  salts.

  The publication "Water Quality Criteria"  of
  the California State Water Pollution  Control
  Board, lists the recommended  limits on
  sulfate in mg/1, shown below in Table 1.
Ill  ANALYTICAL METHODS

 The gravimetric method is recognized as the
 standard procedure and is the most accurate
 and  most time-consuming.  It should be used
 for sulfate in greater concentration than 60
 mg/1.  The turbidimetric procedure is  rapid
 and  more accurate for concentrations less
 than 50 mg/1, but can be used up to 60 mg/1.
 The most rapid method is  the titrimetri'c,
 which is applicable  to solutions containing
 100  mg/1 SO4 or more, where an accuracy of
 + 10% is acceptable, as in boiler water
 analysis.  This procedure is  not applicable to
 Basic Data Network samples. Obviously,
 dilution or concentration of the sample  will
 bring most waters into the desired range for
 any  of the  methods.
*In Charge, Chemistry, Technical Advisory and Investigations Section, DWSPC, SEC.
Reviewed December, 1965.
CH.SUL. Ib. 11.64
                                       14-3

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Sulfate
    Table 1.  RECOMMENDED LIMITS ON SULFATE CONTENT OF INDUSTRIAL WATER
Industrial process
Brewing
Carbonated Beverages
Concrete Corrosion
Ice Making
Milk Industry
Photographic Process
Sugar Making
Textiles
Milligrams per liter
804
--
250
25
--
60
--
20
100
CaSO4
100 - 500
	
	
300
	
100


MgS04
100 - 200
	
	
130 - 300
	
	
	
	
Na2SO4
100
	
	
300
	
	
	
	
A  Gravimetric Procedure

   The gravimetric procedure involves the
   addition of a dilute solution of barium
   chloride to the sample to precipitate
   barium sulfate.  The precipitation is made
   in a solution slightly acidified with HC1
   and near the boiling temperature.  The
   precipitate is  filtered off,  washed with
   water until free of chloride ions, ignited
   at 800C,  and weighed as barium sulfate.
            =  _  mg BaSO4 X 411.5
            4        mi Of sample
B  Turbidimetric Method

   In the more rapid turbidimetric method,
   sulfate ion is precipitated with barium
   ion in acid solution in such manner as to
   form barium sulfate crystals of uniform
   size.  No  other ions are found in normal
   waters that will precipitate with barium
   in acid solution.  Light transmitted by the
   turbid solution is measured with a
   photometer and the sulfate ion concentra-
   tion is read from a standard curve.  Color
    and turbidity must be removed first.  The
    procedure described in Standard Methods
    involves very careful control of stirring
    and the time interval before reading.  A
    modification, used by the Analytical
    Reference Service Laboratory at SEC
    has shown much more consistent results.
IV  PRECISION AND ACCURACY

 The ARS Water Mineral Study of 1961
 reported, on_a reference sample containing
 259 mg/1 804 , that the gravimetric
 procedure remains the most commonly used,
 with the turbidimetric method next.

 The standard deviation for the gravimetric
 method was j^ 11. 9 mg/1, and for the
 turbidimetric method it was 23.9 mg/1.
 REFERENCES

 1  Standard Methods for the Examination of
       Water and Wastewater.  (llth edition)
       APHA, AWWA, WPCF.  1960.

 2  Water Mineral Study of 1961.   Analytical
       Reference Service.  SEC.
14-4

-------
                                                                                 Sulfate
3  Water Quality Criteria.  State Water            4  Public Health Service Interstate Quaran-
      Pollution Control Board.  Sacramento,             tine Drinking Water Standards
      California.  1963.                                 (revised) 1961.  Federal Register,
                                                        pages 6737 - 6740. July 27, 1961.
                                                                                       14-5

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                     ALKALINITY AND RELATIONSHIPS BETWEEN THE
                             VARIOUS TYPES OF ALKALINITIES

                                        Robert C. Kroner*
I PRELIMINARY

The property of water referred to as alkalinity
is usually caused by the presence of hydroxyl,
carbonate and bicarbonate ions.  To a lesser
extent borates,  phosphates and silicates con-
tribute but are generally present in negligible
amounts.
The concentration and ratio of the OH"
and HCOg" ions may be measured by titrating
a sample to certain  specified pH's or end
points which are detected either by use of a
pH meter or by color indicators. Phenol-
phthalein is used for visual detection of the
first end point, (approximately pH 8) which
indicates the neutralization of NaOH and  con-
version of COs to HCO3~.  A number of in-
dicators (methyl orange, methyl purple,  brom
cresol green etc. ) are used for detection of
the  second end point (pH 3-5) which indicates
the  complete conversion of HCOs" to H2O
and CO2-  The final end point is determined
by the amount of COs"~ and HCOs" originally
present in the sample.  If the end points are
determined electrometrically they are taken
as the mid-point of the greatest rate of pH
change per unit volume of titrant.
II  RELATIONSHIPS BETWEEN HYDROXIDE,
   CARBONATE, AND BICARBONATE ALKA-
   LINITIES

 The results obtained from phenolphthalein
 and total alkalinity measurements offer a
 means of classification  of the principal
 forms of alkalinity, if certain assumptions
 are made.  It must first be assumed that
 interferences are absent and that bicar-
 bonate and hydroxide  do not exist in the
 same solution.  According to the system
 presented in Standard Methods,  llth Edition:

 A  Hydroxide alkalinity  is present if the phe-
    nolphthalein alkalinity is  more than one-
    half the total alkalinity.

 B  Carbonate alkalinity  is present if the phe-
    nolphthalein alkalinity is  not zero but is
    less than the total  alkalinity.

 C  Bicarbonate alkalinity is  present if the
    phenolphthalein alkalinity is less than
    one-half the total alkalinity.
          Table 1.  Relationships Between Phenolphthalein Alkalinity, Total Alkalinity,
             Carbonate Alkalinity, Bicarbonate Alkalinity and Hydroxide Alkalinity
Lecture
Notes
Case 1
Case 2
Case 3
Case 4
Case 5
Result of
Titration
P = T
P = YiT
P = O
P > ^T
p < y2T
OH' Alkalinity
as CaCOs
T
0
O
2P-T
O
COs" Alkalinity
as CaCOs
O
2P
O
2(T-P)
2P
HCOs'Alkalinity
as CaCOs
O
O
T
O
T-2P
                    P  = Phenolphthalein Alkalinity
      T = Total Alkalinity
*In Charge, General Laboratory Services, Water Pollution Surveillance System, SEC,  and re-
vised by J.\V.  Mandia, Chemist,  DWSPC Training Activities,  SEC.  Reviewed December  1965.
CH.ALK. 2a. 11.64
                                      14-6

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 Alkalinity and Relationships between the Various Types of Alkalinities
             Table 2.  Stoichiometric Volumes of Solutions of Different Normalities
Standard Solution
Normality
Equivalent Vol-
umes, ml
H2SO4
0.0200
10.0
9.4
10.0
6. 3
NaOH
0.0189
10. 6
10.0
10.5
6.6
Na2CO3
0. 0199
9.9
9.5
10.0
6. 3
NaHCOs
0. 0125
16. 0
15. 1
15. 9
10.0
III  CASE EXAMPLES

 The relationships involved in Table 1 may
 best be explained by reference to the follow-
 ing graphs.  These were prepared  by titrating
 volumes of standard solutions of sodium hy-
 droxide,  sodium carbonate, and sodium bi-
 carbonate with standard sulfuric acid.  The
 stoichiometric volumes of the various solu-
 tions are summarized in Table 2 for conven-
 ience in the interpretation of the charts.

 A  CASE 1 - Where phenolphthalein alkalinity
    = total alkalinity
 pH
                                  P) END POINT
           ML 0. Olfl'l N NfiOH vs 0.020 N HSO
   The sharp break occurs at the point where
   all of the NaOH has been exactly neutral-
   ized by the acid.  The pH and concentration
   of the end products (Na2SO4 and H2O) de-
   termine the pH at the equivalence point
   between NaOH and H2SO4;  in this case,
   approximately 7. 0.
B  CASE 2 - Where phenolphthalein alkalinity
   = one-half the total alkalinity
         I	1	1	1	1	1
                                                            I	I	I	I	i
                                                            5     10     IS     2(1    2r,
                                                                  MI, o.o2ti N n.,so4 AIWKH

                                                            21) Ml, 0.020 N Nn2 CO, vs 0 (12(1 N H2SC>4

                                                                       (P =  ! T)
   The titration proceeds in 2 stages where-
   in all of the CO3~~ is converted,  first to
   HCO3-and finally to H2CO3.  The first
   end point  occurs at approximately pH 8,
   and at exactly half the volume of  acid used
   for the total titration.  The end point
   which  occurs at approximately pH 4 re-
   presents the total alkalinity and requires
   exactly twice the volume of acid used for
   the first end point.

   If either HCOs" or OH" ions had  been pre-
   sent the titration volumes for the curves
   would  not have been of equal magnitude.
 14-7

-------
                             Alkalinity and Relationships between the Various Types of Alkalinities
C CASE 3 - Where phenolphtahlein alkalinity
   = 0
                      -(I1) KND POINT
               I
                    J_
                           I
                               J_
                                     J_
               11)    J5     20     25     i(
               Ml, 0.020 N H^.SO  ADDED

           25 Ml. 0.0125 N NnllCO.  vs, 0.020 N II_SO
                         ,J           24
                       (P  O)
T  The reaction proceeds in one stage with
   the initial pH at approximately 8. 5 and
   final pH at 4. 0.   In this case the phenol-
   phthalein alkalinity is zero and since no
   conversion of 003"~  to HCC>3 is  noted the
   total alkalinity  can only be due to the
   HCOs" ion.

D  CASE 4 - Where phenolphthalein alkalinity
   is  greater than one-half the total alkalinity.
               ML 0.020 N 1USO,  ADDED
       MO MI. 0.
             {11HO N N.iOII t 10 ML o.<
                      (P > j II
120 N N.i CO ~|
   The volume of acid required for the first
   end point (phenolphthalein alkalinity) is
   due to the OH" neutralization and  conver-
   sion of the COs" to HCOs".  The second
   end point represents the complete conver-
                         sion of HCOs" to H2COs.   Referring to
                         Case 2 where the volume of acid was
                         similar for each end point, it is apparent
                         that a base responding to phenolphthalein
                         but which is not COs"" must be present.
                         Since it was originally assumed that OH"
                         and HCOs" do not exist in the same solu-
                         tion we must conclude that the  total alka-
                         linity is due to  OH" and CO3~~.

                      E  CASE 5 - Where phenolphthalein alkalinity
                         is less than one half of the total alkalinity.
                                     Ml, 0 02(1 N H SO  M)l)l I*
                                             2 'I
                     FlO ML 0 020 N Nn.CO  I 10 Ml, II m N N>II(O~]
If, in the reaction NaOH + NaHCO3 
Na2COs  + H2O, the NaOH exists in ex-
cess quantity,  the final sample contains
NaOH and Na2COs,  (Case 4) in which the
volume of acid required for the phenol-
phthalein end point is greater than one-
half the total.  In this case, however,
the situation is reversed,  wherein the
volume of acid required for the HCOs"
end point is greater than one-half the
total.  Referring again to the reaction
NaOH + NaHCO3  Na2COs + H2O, if
NaHCOs  is in excess the end products
must consist of Na2COs  and NaHCOs
and OH"  must be absent.   The end points
consist,  therefore,  of Na2COs  
NaHCOs  (phenolphthalein end point) and
NaHCO3  >
                                                                                         14-8

-------
Alkalinity and Relationships between the Various Types of Alkalinlties
F CASE  6 - Where phenolphthalein alkalinity
   is greater than one-half total alkalinity.
                    15     20     2f>     JO
                ML 0.020  N H..SO  ADDED
       QlO ML 0.0181 N NaOl'l + 10 ML 0,0125 N NnllCO ~| 
                    0.020 N 1LSO,          ' ~*
                           <  4
                      (p > IT}
                                                 IV
                               , (10 +12.6)     .       ,    .,      .   ,
                            and - - 5 -  = volume of acid required
                                    &
                            for conversion of CO3~~ to HCO3~.  The
                                 j   -i     .         ,
                            second end point occurs at
                                                                                 (10 + 12.6)
                                                                                              ,
                                                                                            ml,
                                                      the volume of HCO3~ which is converted
                                                      to H2CO3.  This then becomes the  same
                                                      as Case 4.
                           COMPARISON OF ANALYTICAL METHODS
                           FOR ALKALINITY (According to the
                           Analytical Reference Service Report
                           JAWWA Vol.  55,  No. 5, 1963.)
   Following the original assumption that OH"
   and HCO3~ are not compatible,  with HCO3~
   being converted to CO3~~ we have a con-
   dition similar  to Case 4 (P>l/r).

G CASE 7 - Where phenolphthalein alkalinity
   is greater than one-half total alkalinity.
 pH
                         ~1	1	1	


                         -(P) KNI) POINT

                                 r-(T) KND POINT
                                                                   DETEKMINATION METHODS
                                     TABLE 1Statistical Summary (conld.)
Method
Yer
No of
Vlluei
Reported
Concn.
Added
mj/l
Concn. Determined
iff /I
Mean
Low Hlih
50%
Ranie
!/'
Sundard
Deviation
"I/I
                                              Alkalinity
Methyl orange


Electronic trie


Methyl purple


Mixed indicator

Brom cresol green
All methods


1956
1958
1961
1956
1958
1961
1956
1958
1961
1958
1961
1958
1956
1958
1961
38
19
27
14
53
88
8
10
18
4
15
1
60
92
178
19
17
42.5
19
17
42.5
19
17
42.5
17
42.5
17
19
17
42.5
200
195
43.7
19.7
19.4
44.2
14.7
19.3
44.8
19.5
42.8
19
19.2
19.6
43.9
11.23
16
38
19.0
15
38.9
14.0
18
40
18
39
19
11 23
15
25
30.0
24
50
21.0
25
57
15.2
21
50
20
49
19
300
25
57
 2
 1
 1.5
 1
 2
 2.5
 4
 2
 1.5
 3
 3
 2
 2
 2
 1.9
5.049
2483
3250
0.911
2 740
3.605
0.475
0.823
3081
1.000
3550

4460
2320
5.335
    [lOML 0.0180 N NaOIl + 10 ML 0.020 N NaCOj H  10 ML

          0.012r> N NaHrO(]vs 0.020 N II,,SO4

                    

; T) The first end point occurs at the stoichio- metric sum of the equivalent volumes as follows: (9.4 - 6. 3) + (10 + 12.6) Alkalinity - The methods for alkalinity measurement varied only in the choice of in- dicator or pH for determining the endpoint of the titration. The indicators used included methyl orange, methyl purple, and mixed indicator. The data show that as the use of electrometric endpoint increased, the use of methyl orange decreased. where (9. 4-6.3)= volume of N acid re- quired for excess OH" after OH" + reaction, 14-9


-------
                                ALKALINITY LABORATORY
                                        J. W. Mandia*
 I  REAGENTS AND EQUIPMENT

 A  Reagents

    1  0.02NH2SO4

    2  Phenolphthalein indicator

    3  Methyl orange indicator

    4  Mixed indicator (Brom Cresol Green-
       Methyl Red)

    5  Alkalinity test sample

 B  Equipment

    1  Potentiometer

    2  50 ml burette

    3  Medicine dropper

    4  250 ml beaker

    5  Magnestir and rod

    6  50 ml volumetric pipette

    7  50 ml graduate

    8  Stirring rod


II  PROCEDURE

 A  Phenolphthalein-Methyl Orange
    Determination

    1  Pipette 50 ml of sample into 250 ml
    /  beaker; add 50 ml distilled water.
  ^^3
S ^2  Add phenolphthalein and titrate to
       colorless end point.

    3  Add methyl orange (4 drops) titrate to
       yellowish-gold end point.
   4  Record mis of 0.02N H?SO used for
      each end point and make five
      determinations.

   5  Compute average titration values for
      phenolphthalein alkalinity and calculate
      standard deviation.

   6  Compute methyl orange or total
      alkalinity for each determination using
      the following formula:
Total Alkalinity as
   CaC03 mg/1
Ml H0SO  X N X 50 X 1000
     ^   4
      Mis sample
   7  Compute average value for total
      alkalinity and calculate standard
      deviation.
   -*
B  Phenolphthalein-Mixed Indicator
   Determination

   1  Proceed as outlined above for
      phenolphthalein end point determina-
      tion (II-A).

   2  Add 4 drops of mixed indicator titrate
      to a grey end point pH 4. 8.  This end
      point is used for alkalinities ranging
      from 50  - 200 mg/1.

   3  Titrate  to pink end point pH 4. 6; make
      five determinations.

   4  Compute average titration values for
      phenolphthalein alkalinity and calculate
      standard deviation.

   5  Compute average titration values for
      mixed indicator GREY end point and
      calculate standard deviation.

   6  Compute average value for total        ,
      alkalinity and calculate standard devi-
      ation for mixed indicator PINK end
      point.  Compute total alkalinity  using
      the above formula.
 *Chemist, DWSPC Training Activities, SEC

 CH.ALK. lab. la. 12.65
                                     14-10

-------
Alkalinity Laboratory
C  Electrometric Titration

   1  Place 50 ml of sample and 50 ml of
      distilled water into a 250 ml beaker.

   2  Place magnestir rod in beaker, lift
      pH electrodes from holder and put
      beaker on magnestir.

   3  Insert electrode,  adjust rotation of rod
      to a moderate speed.

   4  Push down on meter button "pH" and
      titrate with rapid drops  to pH 9.5 then
      slowly to pH 8. 3.

   5  Record mis of titrant  used.

   6  Titrate with rapid drops to pH 5.5,
      then add drops slowly until pH 4. 5 is
      reached.  Record mis of titrant  used.
 7  Remove burette to opposite position
    on clamp.

 8  Push down on meter "Stand by" button.
                            \
 9  Lift electrode and rinse into beaker.

10  Pour out sample from beaker, catch
    magnestir rod and rinse.

11  Fill burette with acid and return to
    position for titration.

12  Compute pH 4.5  and pH 8. 3 average
    titration values and calculate standard
    deviation.

13  Compute pH 4.5  total alkalinity using
    above formula for each determination
    and calculate standard deviation.

14  Make  five determinations.
          t-
14-11

-------
                                                                Alkalinity Laboratory
  o
  l-l
  ^


 I

 "o
  0)
 l-l
 H
        00

        oo
                             Ar\
                             ( > '
     PH
(1) W
   So)
   h

TS 

-------

-------
                DETERMINATION OF CALCIUM AND MAGNESIUM HARDNESS
                                       B.  V.  Salotto*
 I   INTRODUCTION
 A  Definition of Hardness

    1   USPHS - "In natural waters,  hardness
       is a characteristic of water which re-
       presents the total concentration of
       just the calcium and magnesium ions
       expressed as calcium carbonate.   If
       present in significant amounts, other
       hardness-producing metallic  ions
       should be included".
    3  Use of water which result in change
       in hardness such as:

       a  Irrigation

       b  Water softening process


 B Objections to Hardness

    1  Soap-destroying properties

    2  Scale formation
 B  Other Definitions in Use

    1  Some confusion exists in understanding
      concept of hardness as a result of
      several definitions presently used.

    2  Soap hardness definition includes
      hydrogen ion because it has the capacity
      to precipitate soap. Present definition
      excludes hydrogen ion because it is not
      considered metallic.               ,
    "J^ ,1 *'}>-<-""''K^-it**  t^V^y'"''"'^ TJA
    3  Other agencies define hardness as "the
      property attributable to presence of
      alkaline-earths".

    4  USPHS definition is best in relation to
      objections of hardness  in water.
II   CAUSE OF HARDNESS IN WATERS OF
    VARIOUS REGIONS OF THE U. S.
  C Removal and Control

    Hardness may be removed and controlled
    through the use  of various softening
    operations such as zeolite,  lime-soda,
    and hot phosphate processes.  It can
    also be removed by simple distillation or
    complex formation with surface active
    agents (detergents).
Ill  DETERMINATION OF TOTAL HARDNESS


 A Three Methods in Use


    1  Soap method

    2  Compleximetric method (EDTA)

    3  Calculation from individual analysis
       of metallic ions other than Na and K.
 A  Variation

    Hardness will vary throughout the country
    depending on:

    1  Leaching action of water traversing
      over and through various types of
      geological formations.

    2  Discharge of industrial and domestic
      wastes to water courses.
 B Compleximetric Method


    1  Principle of determination

       Ethylenediaminetetra acetic acid (EDTA)
       is a  sparingly soluble amino polycar-
       boxylic acid which forms slightly
       ionized and very stable colorless
       complexes with the alkaline-earth
       metals.
*Chemist,  Basic and Applied Sciences Branch, DWS&PC, SEC.

 CH. HAR. 3. 12.65
                                       15-1
                                        <\

-------
Determination of Calcium and Magnesium Hardness
   2  Interferences

      Iron,  manganese, nickel and zinc
      interfere.

   3  Procedure

      Time  and pH considerations.

   4  Calculation of total hardness assuming
      a known vol. of titrant of EDTA.

   5  Precision and accuracy.


C Determination of Calcium Hardness

   1  Principle of determinations

      Murexide indicator forms a salmon-
      colored complex with calcium whose
      ionization constant is of a higher
      value  than that of the CaEDTA complex.

   2  Interferences

      Heavy metals  and Sr interfere

   3  Procedure

      Time  of titration and proper lighting
      conditions are critical factors.

   4  Calculation of Ca hardness.

   5  Precision and accuracy.


D Determination of Magnesium Hardness

   1  Calculation by difference method most
      commonly used.
   2  Equivalent of Ca hardness is subtrac-  
      ted from total hardness equivalents, the
      difference attributable to magnesium
      equivalents.

   3  Other methods such as pyrophosphate
      method where calculation by difference
      method cannot be used.
REFERENCES

1  American Public Health Assoc. ,  and
      others.  Standard Methods for the
      Examination of Water, Sewage, and
      Industrial Wastes.  10th Edition.  1955.

2  Ibid,  llth Edition.   1960.

3  Barnard, A.  J., Jr.,  Broad, W. C. , and
      Flaschka, H. The EDTA Titration.
      J.  T.  Baker Company.  1957.

4  U.S. Public Health Service.  Drinking
      Water Standards.  U.S. Public Health
      Service Report,  Vol.  61,  No.  11,
      1946.

5  Rainwater, R. H. ,  and Thatcher, L.L.
      Methods for the  Collection and Analy-
      sis of Water Samples.  U. S. Geological
      Survey Water Supply. Paper 1454.
      1960.
15-2

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                        LABORATORY PROCEDURE FOR HARDNESS

                                       J.  W. Mandia*
Determination of Total Hardness,  Calcium
and Magnesium Hardness

I  REAGENTS

A  Buffer Solution

   Dissolve 16. 9 g ammonium chloride,
   NH4C1 in 143 ml cone, ammonium hydrox-
   ide, NH4OHPH-10.

B  Na2EDTA Solution

   Dissolve 4. 0 g Na2EDTA and 0. 10 g
   MgCl2- 6H2O in 800 ml distilled water.
   Standardize  against standard calcium solu-
   tion and adjust so that 1. 0 ml = 1. 00 mg
   CaCOs.  This usually requires the addition
   of between 100 to 200 ml of distilled water.

C  Standard Calcium Solution

   Weigh 1. 000 g of calcium carbonate, which
   has been dried overnight at 105C,  into a
   500 ml Erlenmeyer flask.  Add dilute
   HC1 until all the CaCOs  is dissolved.  Add
   200 ml distilled water and boil  for a few
   minutes to expel CO2.   Cool, add a few
   drops methyl red indicator,  and adjust to
   the intermediate orange color with dilute
   NH4OH or dilute HC1 as required.  Make
   up to  1 liter with distilled water.   1 ml =
   1. 000 mg CaCO3.

D  Total  Hardness Indicator

   Mix 0. 4 g Eriochrome Black T plus 100  g
   NaCl to prepare a  dry powder mixture.

E  Calcium Hardness Indicator

   (Calcein) grind together in a mortar 0. 2  g
   calcein (G. Frederick Smith Co.) 0. 12 g
   thymolphthalein and 20 g KC1.
 II  PROCEDURES

 A Total Hardness

    1  Place 25 ml sample diluted to 50 ml
       with distilled water in a  125 ml Erlen-
       meyer flask.

    2  Add 1 ml buffer and mix.   Check pH.
       If it is not pH  10, add dilute NaOH
       dropwise to adjust.

    3  Add indicator.

    4  Titrate slowly with Na2EDTA until the
       last reddish tinge disappears from the
       solution, adding the last few drops
       dropwise at 3 to 5 second intervals.

 B Calcium Hardness

    To a neutral 25 ml aliquot of sample, add
    0. 2 M sodium carbonate. Add 10% sodium
    hydroxide and adjust pH to 12. 5 with pH
    meter. Add calcein indicator and titrate
    with Na2EDTA.
Ill  CALCULATIONS OF TOTAL HARDNESS
    AND CALCIUM FROM RESULTS OF
    COMPLEXIMETRIC DETERMINATIONS.
    CALCULATION OF  MAGNESIUM BY
    DIFFERENCE

 A Total Hardness as CaCOs

    1  Assume a 25 ml water sample size and
       a titrant volume of 6. 00 ml of 0. 010 M
       Na2EDTA solution.

    2  1. 0 ml 0. 010 M Na2EDTA solution =
       1 mg
                                                                               CaCO
*Chemist,  DWS&PC Training Activities,  SEC.
CH.HAR. lab. 1. 12. 65
                                                                                       15-3

-------
Laboratory Procedure for Hardness
B  Calcium Hardness

   1  Assume 25 ml water sample and a
      titrant volume of 5. 00 ml of 0. 010 M
      Na2EDTA

   2  Imlof 0. 010MNa2EDTA = 0.4mgCa
   1 mg CaCOg    Ca
                    (40)
       ml
   CaCOgUOO)
ml
                          ml
                              = 0. 4mgCa/ml
                              =80mg/lCa
C  Magnesium - Calculation by difference in
   the same water sample.

   1 Assume that the total hardness contri-
     bution results only from calcium and
     magnesium ions in solution.

   2 Calculation of  meq/1
240 mg/1 CaCO  X 0. 02 meq/mg = 4. 80 meq/1
              O
                                   D Sodium Absorption Ratio

                                     1  Sodium absorption ratio =
Na +
                                                                      +
                                     2  Soft water:  25 mg/1 total hardness as
                                        CaCO3
                                                    200 mg/1 sodium as Na+
                                                       a  25 mg/1 X 0. 02 = 0. 50 meq/1

                                                       b  200 X 0. 0435 = 8. 70 meq/1
                                                                   8. 70
                                                                                     .
                                                                          7. 4 approximately
                                        This is a high sodium hazard water.


                                      4  Hard water:

                                        100 mg/1 X 0. 02 = 2. 00 meq/1 total hardness

                                        20 mg/1 X 0. 0435= 0. 87

                                        This is a low sodium hazard water.
80 mg/1 Ca  X 0. 0499 meq/mg = 4. 00 meq/1


   3  Total hardness =          4. 80 meq/1

      Calcium hardness =       4. 00 meq/1

      Magnesium hardness =    0. 80 meq/1

   4  0. 80meq/lMg X 12. 16 mg/meq = 9. 7 mg/1 Mg
                                   REFERENCES

                                   1  Standard Methods for Examination of
                                        Water and Wastewater,  llth Edition.

                                   2  Analytical Reference Service Laboratory
                                        Procedures.

                                   3  U.  S.  Salinity Laboratory Handbook.
                                      No.  60.  1954.
15-4

-------
                       LABORATORY EXERCISE FOR THE STUDY
                          OF VARIOUS HARDNESS INDICATORS
                                      J. W. Mandia*
I  STANDARDIZATION OF Na2EDTA
   SOLUTION

A  Eriochrome BJack T Indicator

   1  Pipette 10 ml of standard CaCOg
      solution into 250 ml beaker.

   2  Add 90 ml of distilled H2O.

   3  Add 2 ml of pH 10 buffer and 4 drops
      of SNNaOH.

   4  Add a small amount of Eriochrome
      black T.

   5  Titrate to a distinct blue color.

   6  Make 5 determinations  using Erio-
      chrome black T indicator.
                                           fi
   7  Compute  average Mis of titrant used,  ''j.'A

   8  Calculate the factor for  Na2EDTA.   \.&1

      a  1  ml of CaCOo solution =  1 mg of
        hardness as CaCOq
b  1 ml of 0. DIM Na2EDTA =  1 mg
   hardness as CaCOg

c  Factor for Na2EDTA = mis
   CaCO3/mls N
                                       of
   9  Compute the average factor value for
      Na2EDTA
      deviation.
Na2EDTA and calculate standard
  10  Compute hardness values using Erio-
      chrome black T indicator using
      Na2EDTA standardized with this
      indicator.

  11  Hardness formula

 ,,  ,   ,        Mis Na9EDTA X F X 1000
Mg/1  hardness  _ 	^	
     as CaCOg         Mis sample
 B  Univer I Indicator

    1  Proceed as described in I-A.

    2  Add Univer I indicator instead of
      Eriochrome black T.

    3  Titrate to a distinct blue color.

    4  Make 5 determinations using Univer I
      indicator.

    5  Calculate average factor value for
      Na2EDTA using this indicator and
      compute standard deviation.

 C  Calmagite Indicator

    1  Proceed as described in I-A.

    2  Add 4 drops of Calmagite.

    3  Titrate to a distinct blue color.

    4  Make 5 determinations using Calmagite
      indicator.

    5  Calculate average factor value for
      NagEDTA using Calmagite indicator
      and compute standard deviation.


II   ANALYSIS OF HARDNESS SAMPLE

 A  Eriochrome Black T Indicator

    1  Pipette 50  ml  of hardness sample into
      a 250 ml beaker.

    2  Add 50 ml  of distilled water.

    3  Add 2 ml of pH 10 buffer and 8 drops
      of SNNaOH.

    4  Add a small amount of Eriochrome
      black T.
*Chemist, DWSPC Training Activities,  SEC.

CH. HAR.lab. 2. 12. 65
                                                                                15-5

-------
 Laboratory Exercise of Various Hardness Indicators
    5  Titrate to a distinct blue color.

    6  Make 3 determinations using this
       indicator.

    7  Calculate hardness using the formula:

                      Mis Na2EDTA X F
 Mg/1 hardness _ (determined with EBT) X 1000
     as CaCO3          Mis of Sample

 B Univer I Indicator

    1  Proceed  as described in II-A.

    2  Add a small amount of Univer I.

    3  Titrate to a distinct blue color.

    4  Make 3 determinations using this
       indicator.

    5  Calculate hardness using the formula:

                 Mis Na2EDTA X F (determined
 Mg/1 hardness _  	with Univer I) X 1000
     as CaCO;
Mis of Sample
 C  Calmagite Indicator

    1  Proceed as described in II-A.

    2  Add 4 drops of Calmagite.

    3  Titrate to a distinct blue color.

    4  Make 3 determinations using this
       indicator.

    5  Calculate hardness using the formula:
                Mis Na2EDTA X F (determined
Mg/1 hardness _     with Calmagite) X 1000
     as CaCOg "        Mis of Sample


III  DETERMINATION OF CALCIUM
    HARDNESS

 A  Calver I Indicator

    1  Add 100 ml of hardness sample with
       graduate  into 250 ml beaker.

    2  Add 4 drops of SNNaOH, (this adjusts
       to pH 12).
    3  Add a small amount of Calver I.
                             ]
    4  Titrate from pink to a distinct purple
       color.

  , 5  Make 2 determinations.

    6  Calculate calcium hardness

                     Mis Na2EDTA X F
 Mg/1 Ca hardness _ (best  result) X 1000
        as CaCO3 ~     Mis Sample

  B Calver II Indicator

    1  Proceed  as in III-A only add Calver II
       instead of Calver I.

    2  Make 2 determinations.

    3  Titrate rose to blue end point.

    4  Calculate calcium hardness.

  C Determination of Magnesium Hardness

    1  Subtract  mg/1 Ca hardness as CaCOg
       from total hardness as CaCOg.

    2  Mg/1 Mg as CaCO3  = T.H as
       CaCOg 	Ca.H as CaCOg


IV  HARDNESS  INTERFERENCE WITH IRON

  A Eriochrome Black T Indicator

    1  Proceed  as in II-A  using Iron hardness
       sample.

    2  Observe  change in color of indicator.
       It is atypical.

    3  Make 3 determinations.

    4  Calculate hardness.

  B Univer I Indicator

    1  Proceed  as in II-B.

    2  Observe  color change.

    3  Make 3 determinations.

    4  Calculate hardness.
 15-6

-------
                                         Laboratory Exercise of Various Hardness Indicators
C  Calmagite Indicator

   1  Proceed as in II-C.

   2  Observe change in color.

   3  Make 3 determinations.

   4  Calculate hardness.
REFERENCES

1  Standard Methods for Examination of
      Water & Waste Water,  1960.

2  Water and Sewage Analysis Procedures
      Cat.  #9, Hack Chemical Co.
                                                                                     15-7

-------
  Laboratory Exercise of Various Hardness Indicators
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-------

-------
                                  FLAME PHOTOMETRY

                                    Robert C. Kroner*
I  PRELIMINARY

Flame photometry is the art and science of
applying thermal energy (heat) to elements
in order to effect orbital shifts which produce
measureable characteristic radiations.  The
color of the emission and the intensity of
brightness of emission permit both qualitative
and quantitative identification.

The application of a very hot flame (2000C
or more) produces  excitation of the element,
caused by the raising of an electron to a
higher energy level and is followed by the
loss of a small amount of energy in form of
radiant energy  as the electron falls back into
its original position or to a lower energy level.
II   INSTRUMENTATION

 The six essential parts of a flame photo-
 meter are: the pressure regulators and
 flow meters for the fuel gases,  the atomizer,
 the burner, the optical system, the photo-
 sensitive detector, and an instrument for
 indicating or recording output of the detector.
 These components  are schematically shown
 in  Figure  1.

 A  The Atomizer and Burner

    Numerous variations in atomizer and
    burner design have been used. Figure 2
    depicts the integral aspirator-burner used
    in Beckman instruments.
                                  YELLOW
    COLLIMATING
    MIRROR
                               PRISM   BLUff-SLIT
                                       GREEN
                                                                             METER
              SAMPLE

        ATOMIZER  BURNER
                 FIGURE 1. SIMPLIFIED DIAGRAM OF A  FLAME PHOTOMETER
*In Charge,  General Laboratory Services,  Water Pollution Surveillance System,  DWS&PC, SEC,
and revised  by R. J.  Lishka,  Chemist, Analytical Reference Service, Training Program,  SEC.
Reviewed December 1965.
CH. MET. 16c.5.65
                                      16-1

-------
Flame Photometry
                              Fuel
                              ' Oxygen
                Sample

   Figure 2.  DETAILED DIAGRAM OF
          BURNER-ATOMIZER      OL
   The sample is introduced through the inner-
   most concentric tube,  a vertical palladium
   capillary.  A concentric channel provides
   oxygen, and its tip is constricted to form
   an orifice.  Oxygen is passed from this
   orifice causing the sample solution to be
   drawn up to the tip of the  inner capillary.
   There the liquid is sheared off and dis-
   persed into droplets.  All droplets are
   introduced directly into flame, with a
   sample consumption of 1 to 2 ml/min.

   The main requirement of the burner is
   production of a steady flame when supplied
   with fuel and oxygen or air at constant
   pressures.  In the Beckman aspirator-
   burner, a concentric channel provides
   oxygen to operate  the atomizer and the
   flame.   The additional concentric channel
   provides fuel for the flame.

B  Optical System,  Photosensitive Detector,
   and Amplifier

   The optical system must collect the light
   from the steadiest part of the flame,  render
   it monochromatic  with a prism,  grating or
   filters,  and then focus it onto the photo-
   sensitive surface of the detector.  Use  of
   filter photometers is least desirable  due
   to their limited resolution.  Flame spec-
   trophotometers improve application
III
    as they will separate emissions in a mix-*
    ture of metals, such as the manganese
    lines at 403. 3 mjj. and the potassium lines
    at 404. 6 m^.  Placement of a concave
    mirror behind the flame so that the flame
    is at the center of curvature,  increases
    intensity of flame emission by factor of
    two.

    Any photosensitive device may be used in
    a flame photometer.  The detector must
    have a response in the portion of the spec-
    trum to be used and have good sensitivity.
    The photomultiplier tube is the preferred
    detector for flame  spectrophotometers.

    The amplifier increases the signal from
    the phototube and improves resolution
    between close spectral lines.   It also
    permits identification of elements pre-
    sent in samples when the concentration
    is very small.
APPLICATIONS OF FLAME PHOTO-
METRY TO WATER ANALYSES
 Measurement of sodium and potassium in the
 past has been confined to complex,  tedious,
 and time-consuming gravimetric procedures.
 The flame technique enables the analyst to
 perform these determinations in a matter of
 seconds.   If these metals alone were the
 only elements capable of measurement by
 flame photometry the  use of the  instrument
 could still be  justified in a  great many
 laboratories.

 Other cations which may be detected  and
 measured in waters and waste materials
 are calcium,  magnesium,  lithium,  copper,
 and others.  Table 1 includes those elements
 which may be measured with commercially
 available equipment including ultra-violet
 and photomultiplier accessories.

 Table ] does not include wavebands which
 occur in the infrared spectrum.   Sodium, for
 example, has an emission band at 819 m(j.
 which is not detectable with the common
 instruments.

 Many other metals, including the rare earths,
 can be measured using the  flame technique,
 but they are not included in the table  because
16-2

-------
                                         Flame Photometry
                Table  1

Aluminum


Barium


Beryllium

Boron



Cadmium


Calcium



Chromium



Copper


Iron



Wavelength
484. 2
467. 2
396. 2
553. 6
493

471
510
548
521
495
9
326. 1"
228. 8*

422. 7
622
554

425.4
360?
520

324"
327?

372
386
373

Approximate
Sensitivity
mg/1
2
3
4
0. 3
0. 4

25
100
1
2
3

2
40

0.003
0. 004
0.01

0. 1
0. 1
0. 1

0.01
0.01

0. 2
0. 2
0. 3


Lead


Lithium

Magnesium


Manganese



Mercury

Potassium



Silver


Sodium


Strontium



Zinc

Wavelength
405,
368,
364'
670. 8

371,
383"
285. 2
403^
279*
561

235. 7*

766. 5
404.6,
344. T
9
338. 3,
328. 1'

589. 3,
330. 3'

460. 7
681
407. 8

213. 9*
500
Approximate
Sensitivity
mg/1
2
2
3
0.002

0. 1
0. 1
0. 2
0.01
1
2

10

0.001
0. 2
3

0.05
0. 1

0.002
1

0.02
0.01
0. 5

500
200
*  =   Ultra-violet spectrum
?  =   Doubtful detection in visible spectrum
                                                             16-3

-------
 Flame Photometry
 the necessity for their measurement in water
 is a rare occurrence.
IV INTERFERENCES

 A Spectroscopic Interferences

   Energy at  other wavelengths or from other
   elements than those intended to be meas-
   ured may reach the detector.  This prob-
   lem is related to the resolution of the
   instrument and slit widths used.

   Many of the instrumental difficulties are
   related to  reproducibility of the flame.
   The quality and composition of the fuel
   affect the constancy and temperature of
   the flame which in turn influences the
   energy of emission.  Likewise, slight
   variations in fuel pressures and ratio
   affect the reproducibility of the flame with
   reference  to shape, temperature,  back-
   ground,  rate of sample consumption,  etc.
   In some cases the temperature of the
   flame is the limiting factor in whether a
   metal may be determined.  (The alkaline
   earth metals emit radiations at "low"
   temperatures whereas other metals re-
   quire very "hot" flames.)  Table  2 indicates
   temperatures obtainable with different fuel-
   oxidant mixtures.
                   Table 2

        Approximate Temperatures of
          Fuel-Oxidant Mixtures for
           Flame Photometer Use
Fuel-Oxidant
Hydrogen - air
Hydrogen - oxygen
Acetylene - oxygen
Acetylene - air*
Propane - oxygen
Illuminating gas - oxygen
Cyanogen - oxygen**
Approximate
Temp. ,C
2100
2700 - 2800
3100
2000 - 2200
2700 - 2800
2800
4900
  * Undesirable because of carbon deposits
  -1* Used in research problems
Emission reading of spectral lines always   *
include any contribution from the  flame
background emission on which the line  is
superimposed.  When the photometer includes
a monochromator,  it is possible to read the
background radiation in the presence of the
test element.  F'irst, the line + background
intensity is measured in the normal manner
at the peak or crest of the band system.
Next,  the wavelength dial is  rotated slowly
until emission readings decrease  to a mini-
mum at a wavelength located  off to one side
or the  other of the emission line or band.   It
is usually preferable to  read  the background
at a lower wavelength than the peak.  Back-
ground reading  is subtracted from the line
+ background  reading.

Products of combustion may affect the
characteristics  of the flame or may affect
the optical system by fogging or coating of
lenses and mirrors.

B Factors Related to the Composition of
   the  Sample

   An  element may be self-absorbing,  a
   phenomenon in which the energy of excita-,,
   tion is not  proportional to  the concentra-  '
   tion of the  element.  As previously  dis-
   cussed, excitation is followed by loss of
   energy in the form of radiation as the
   electron falls back to its original position
   or to a lower energy level. During passage
   of radiant energy through the outer  fringes
   of the flame,  this energy is subject to
   absorption through collision with atoms of
   its  own kind present in the ground energy
   level.  Absorption of radiant energy weakens
   the  strength of the spectrum line.  Using
   the  emission line  at 589 m^i for sodium,
   Figure 3 indicates that the line ceases to
   be linear at 13 ppm.  As the sodium con-
   centration  increases, the self-absorption
   effects become more pronounced.  Sample
   dilution to  permit reading  on linear portion
   of the curve is often practiced.

   Two or more elements present in the
   sample may produce  radiant energy at
   the  same or near  the same wavelength.
   For instance, calcium at 423 mp.  and
   chromium  at 425 mp. could interfere with
   each other by additive affect.  The cor-
   rection may be to dilute out the unwanted
 16-4

-------
                                                                      Flame Photometry
   metal or measure one of the emissions at
   a different wavelength.

       STANDARD CURVE FOR SODIUM
                   10                20
                 mg/1 Sodium
                   Figure 3

   The emission energy of one element may
   be enhanced or depressed by energies
   from other elements.  This phenomenon
   ( radiation interference) occurs when one
   element causes  another element to modify
   its actual emission intensity in either a
   negative  or positive manner.  Correction
   is obtained by dilution or by controlled
   interference addition.

   Other types of difficulties encountered  are
   too numerous to list here.  In general,  they
   may be overcome by improved instruments
   (higher resolution, narrower slit openings,
   optics, flame adjustment) or possibly by
   special techniques.

   Some inexpensive instruments, designed
   for limited use,  may employ illuminating
   gas with  air, or propane with air as a
   matter of economy or convenience.
V  TECHNIQUES

The following techniques are intended to
serve as examples of current procedures in
use for routine samples and for special sam-
ples where corrective procedures are
indicated.

A  Emission Intensity vs. Concentration

   This is the classical procedure in flame
   photometry.  Solutions (standards) con-
   taining known concentrations of test
   element are compared with an unknown
   sample.  This technique is applicable only
   when no interference is present.

B  Radiation Buffers

   For measurements of alkaline earth metals
   (sodium, potassium,  calcium,  magnesium)
   radiation buffers are prepared as solutions
   saturated with regard to each metal re-
   spectively.  A potassium buffer,  for
   example, is prepared by saturating dis-
   tilled water with sodium, calcium, and
   magnesium chloride.  A calcium buffer
   in turn is saturated with sodium, potassium,
   and magnesium chloride.

C  Preparation of Radiation Buffers

   For a sodium measurement, the  buffer
   solution is added equally to samples and
   standards  so that the interferences are
   alike for all readings,  thereby cancelling
   each other.  See Table 3.

D  Instrument Improvement

   Potassium emits energy bands at 766,  405,
   and 345 m^.  The bands are at opposite
   ends of the spectrum and the 405 and 345
   bands are  not usable in the visible spec-
   trum.  The 766 line also loses sensitivity
   because of its proximity to the infrared
   region.  Use of  a red sensitive phototube
   or photomultiplier, however, permit
   measurement with an ordinary instrument
   at concentrations as low as 0. 1 mg/1 or
   less.  This approach is applicable to other
   elements also.

E  Standard Addition

   Equal volumes of the sample are added to
   a series of standard solutions containing
   different known quantities of test element,
   all diluted to the same volume.  See Table
   4.  Emission intensities of the resulting
   solutions are then  determined at  the wave-
   length of maximum emission and at a suit-
   able point  on the flame background.  After
   subtracting the background emission, the
   resulting net emissions are plotted linear-
   ly against the concentration of the incre-
   ments of the standard solutions that were
   mixed with the unknown.  The % transmission
                                                                                        16-5

-------
Flame Photometry
                                           Table 3

Sodium Buffer
Potassium "
Calcium "
Magnesium "
NaCl
-
+
+
+
KC1
+
-
+
+
CaCl2
+
+
-
+
MgCl2
+
+
+
-
                                           Table 4
Cone, of standards
Vol. of standard added
to sample
Vol. of sample used
Concentration of element in
each portion of mixture
0.0 mg/1
10.0 ml
10 ml
|+0 mg/1
5.0 mg/1
10. 0 ml
10 ml
|+2.5 mg/1
10 mg/1
10. 0 ml
10 ml
| + 5 mg/1
   of the mixture containing unknown sample
   and zero standard (distilled water)  is
   doubled and the concentration correspond-
   ing to this point on the graph will be the
   concentration of the undiluted unknown
   sample.  This can be explained algebraical-
   ly in conjunction with Figure 4.

F  Internal-Standard  Method

   The method consists of adding to each
   sample  and  standard a fixed quantity of
   internal standard element.  The element
   must be one not already present in  sample.
   Lithium is  usually the internal standard
   used.  This method is most convenient
   when using instruments having dual
   detectors.  The emission intensities of
   standards and samples are read simul-
   taneously or successively depending upon
   instrumentation.

G  Separation  of Interferences

   In cases  where certain elements interfere,
   they may be physically removed, or the
   interference may be "blocked out" by
   reading the emission at different wave-
   lengths.  To measure lithium,  for ex-
   ample, calcium, barium, and strontium
   are precipitated as carbonates of the
   metals.  The lithium is retained in the
   filtrate and measured at a wavelength of
   671 m\i..
16-6

-------
                                                                 Flame Photometry
               s
               o
               en
               w
               r-l

               ra
               rt
               E-1   20  
                   10  
                    (f+0)
(ft2.5)
5)
                                   Concent rat ion-mg/1
                                                                  10
             (|f5)
Let x  =  concentration of element in
         unknown sample.

Then Y = % transmission of an equal
           mixture of unknown sample
           and zero standard, or
         x   0
     Y = -^ + -^ which simplifies to  2Y =  x
. ' .   2Y = -5-+ 3. 5 (from the example in
                  Figure 4)
by substitution,  x =  + 3.5
                                                                  x = 7 mg/1
                                        Figure 4
                                                                                       16-7

-------
Flame Photometry
BIBLIOGRAPHY

1  Kingsley,  George R. and Schaffert,
      Roscoe R.  Direct Microdetermination
      of Sodium,  Potassium, and Calcium in
      a Single Biological Specimen with the
      Model Du Flame Spectrophotometer and
      Photomultiplier Attachment.  Analytical
      Chemistry.  25:  1937-41.  1953.

2  Gilbert, Paul T., Jr.  Flame Photometry -
      New Precision in Elemental Analysis.
      Industrial Laboratories.  (Beckman Re-
      print R-56)  August,  1952.

3  Detection  Limits for the Beckman Model
      Du Flame Spectrophotometer.   Data
      Sheet 1.  Beckman Publication.  April
      1952.

4  Baker, G. L.  and Johnson,  L. H.  Inter-
      ference of Anions on Calcium Emission
      in Flame Photometry.  Analytical
      Chemistry. 26:465-568.  1954.

5  West,  P.W., Folse, P., and Montgomery,
      D.  The Application of Flame Spectro-
      photometry to Water Analysis. Analytical
      Chemistry. 22:  667. Beckman  Reprint
      R-40.  Model  10300.  1950.
6  Scott, R. K.,  Marcy, V.M., and Hronas,  *
      J. J.  The  Flame Photometer in the
      Analysis of Water and Water-Formed
      Deposits.  ASTM Bulletin. Model 10300.
      (Abs.) May, 1951.  p 12.

 7  Burriel, F.,  Marte, and Ramirez, J.
      Flame Photometry.  Munoz Elsevier
      Publishing Company.  New York.  1957.

 8  Chow, T. J.,  and Thompson, T. G.
      Standard Addition Method.  Analytical
      Chemistry. 27: 18-21.   1955.
 TEXTS

 1  Willard, H. H.,  Merritt,  L. L., and
      Dean, J. A.  Instrumental Methods of
      Analysis. D.  Van Nostrand Company,
      Inc.  New York.  1958.

 2  Dean,  J. A.  Flame Photometry.  McGraw-
      Hill Book Company. New York.  1960.

 3  Clark, G. L.   The Encyclopedia of
      Spectroscopy.  Reinhold Publishing
      Corporation.  New York.   1960.

-------
               USE OF CONDUCTANCE MEASUREMENTS IN WATER ANALYSIS

                                      D. G.  Ballinger*
I THEORETICAL PRINCIPLES

A  Ionic Transfer

   An electrolyte in solution transfers electric
   current by means of ion migration. Under
   the influence of attractive forces, positive
   ions (cations) migrate toward the cathode,
   and negative ions (anions) migrate toward
   the anode.  Upon reaching the respective
   electrode, the ions gain or lose charge,
   thus transferring the charge to the external
   circuit.

B  Variables

   The migration of ions, and thus the magni-
   tude of the current flowing, is a function
   of a number of variables.

   1 Magnitude of EMF - The current flow-
     ing through the system is directly pro-
     portional to the external current applied.

   2 Ion mobility - The ability of the  ions
     to carry the current depends on  the
     charge on the ion and on its size.  The
     common ions show a wide variability
     in ion mobility.

   3 Temperature - In common with most
     electronic transfers,  the migration
     current is directly proportional to
     the temperature of the solution. The
     mobility of most ions  increases ap-
     proximately 2% for a 1 increase in
     temperature.

   4 Electrode area - Since a larger elec-
     trode surface provides greater space
     for the release or acceptance of charge,
     the current is directly proportional to
     the electrode area.

   5 Distance  - The magnitude  of the cur-
     rent depends  on the distance  ions must
     travel before  reaching the electrode.
   6  Number of ions - When a current is
      flowing through an electrolyte,  each
      ion carries the same amount of cur-
      rent.  Therefore, the greater the
      number of ions present,  the greater
      will be the current transferred.  Fur-
      ther, the total current flowing is the
      sum of the currents carried by the
      positive and negative ions respectively.

      Although the ionic transfer is in balance,
      i. e., an equal charge is carried by the
      cations and anions,  the current trans-
      fer is independent of the nature of  the
      opposing ion.  For example, a given
      number of chloride ions will carry a
      particular amount of current, regard-
      less of whether the cations present are
      sodium, potassium, calcium or mag-
      nesium.

      If all of the variables  discussed above
      are held constant, the electrical con-
      ductance of a solution is directly pro-
      portional to the concentration of electro -
      lyte.  This principle is utilized in the
      measurement of the total ion concen-
      tration of a water sample.

C  Specific Conductance

   The conductance of a solution is actually
   measured in terms of resistance to current.
   Such resistance is customarily measuredin
   ohms and the conductance is expressedin re-
   ciprocal ohms ("ohms) or mhos. Because
   of the variables discussedinB. , conductance
   must be defined under specific conditions.

   Specific Conductance is the reciprocal of
   the resistance measured between two
   electrodes one centimeter apart and 1
   square centimeter in cross section.

   Tables of the specific conductance of  the
   common electrolytes are available in
   chemical handbooks.
*In Charge, Chemistry,  Technical Advisory and Investigations Section,  DWS&PC, SEC.
Reviewed December 1965.
CH.MET. 15. 12.63
                                                                                         17-1

-------
Use of Conductance Measurements in Water Analysis
II APPARATUS

To measure the  conductance of a solution,  a
special cell is constructed to act as one of
the resistances of the familiar Wheatstone
Bridge.

A  CeU

   Two thin platinum discs are suspended
   about  1 cm. apart inside a glass shell.
   A coating of finely divided platinum (plati-
   num black) is electroplated on the  discs
   to form the electrode surface.  Because
   of the difficulty of preparing and main-
   taining an electrode surface exactly 1 sq.
   cm. in area,  the cell is constructed to ap-
   proximately the dimensions required and
   a cell constant or factor is determined.  A
   dipping-type  cell is shown in Figure 1.
    of the conductance instrument.  To pro-
    vide for a wide range of conductance
    measurements, a series of resistances is
    included in the bridge circuit.  A null
    point galvanometer and slide wire are
    used to balance the bridge and  indicate
    the  resistance of the sample.

 C  Current

    Alternating current is used to prevent
    polarization of electrodes.
HI PROCEDURE

 A Calibration

    Before making the actual measurements
    of conductance, the cell  constant must be
    determined.  Using the identical cell and
    bridge,  the resistance of a standard elec-
    trolyte solution is carefully measured at
    a constant  temperature.   U.01 N KC1 is
    generally used, since its resistance has
    been accurately determined.  The meas-
    ured resistance is used in the formula
K =
0.
0014118
XR
                                                    where:

                                                                  K = cell constant at 25C

                                                                  R = measured resistance

                                                          0.0014118 = specific conductance of
                                                                      0.01N KC1 at 25C

                                                    Cells are commercially available having
                                                    cell constants of approximately 0.1,  1.0,
                                                    and 10.

                                                  B Measurement
           CONDUCTIVITY CELL
                FIGURE 1
    The cell constant and the specific conduc-
    tance of the sample  are measured as
    follows:
B Bridge

   The Wheatstone Bridge,  designed for
   measuring resistances, is the major part
       Place 4 identical tubes of standard KC1
       solution and 2 tubes of sample  in  a
       water bath at 20 - 30C.  Allow 30
       minutes for temperature equilibrium.
  17-2

-------
                                          Use of Conductance Measurements in Water Analysis
      Rinse the conductivity cell in 3 of the
      tubes of KC1 solution and measure the
      conductance of the 4th.  Record this
      value as
    3  Rinse the cell thoroughly in the first
      tube of the sample and measure the
      conductance of the second tube. Re-
      cord  this value as Rs.

    4  Calculate the specific conductance (in
      H mhos)  of the sample by the formula
       Sp. Cond.
1.411.8 X RKC1
     Re
IV APPLICATIONS

 A  Total Dissolved Residue

    The conductivity of natural waters is di-
    rectly related to the concentration of dis-
    solved solids.  The measurement of con-
    ductivity is very rapid, does not destroy
    the sample, and has good precision.

    The specific conductance of a particular
    sample depends on the nature of the ions
   present,  so that no universal relationship
   can be determined for the ratio of con-
   ductance to total dissolved solids.  On a
   particular water, however, the corre-
   lation can be determined experimentally
   and used to provide a rapid, convenient
   index of the total ionic concentration.
   The ratio of TDS to specific conductance
   for several different water samples is
   shown in Table I.

   Note that the specific conductance varies
   directly with TDS. It is interesting, how-
   ever, to note the difference in ratio of the
   Arkansas River samples at two stations.
   The lower ratio at Ponca City is probably
   due  to the increase in chlorides, as shown
   in Table H.

   It is apparent that the nature of the ions
   present must be considered in any inter-
   pretation of conductance-dissolved solids
   relationships.


B  Checking Mineral Analysis

   Because of the relationship of  specific
   conductance to ionic  concentration, con-
   ductivity may be used to verify the results
                                          TABLE I
Sample
Arkansas River at
Coolidge, Kansas
Arkansas River at
Ponca City, Okla.
Colorado River
Cincinnati tap
Sp. Cond. (nmhos)
3330
1920
1000
590
TDS(mg/l)
2600
1040
680
430
RATIO TDS/cond.
0.73
0.54
0.68
0.73
                                          TABLE II

At Coolidge
At Ponca City
Chloride
80
250
Sp. Cond.
3300
1920
TDS
2600
1040
RATIO TDS/cond.
0.78
0.54
                                                                                      17-3

-------
Use of Conductance Measurements in Water Analysis
    of mineral analyses of water samples.
    Rossum^' found that a satisfactory cor-
    relation could be obtained in 92% of the
    samples investigated.  Equivalent con-
    ductance of the common ions is shown in
    Table III.
TABLE HI
ION
Cl
S04
C03
HC03
N03
Ca
Mg
Na
H mhos per mg/1 (25C)
2.14
1.54
2.82
0.71
1.15
2.60
3.82
2.16
    In practice,  the concentration of each ion
    (mg/1) is multiplied by the appropriate
    factor and the sum of the individual con-
    ductances is calculated.  This value
    should agree with the specific conduc-
    tance of the  sample,  within + 2%.  For
    best results, the sample should be di-
    luted to  Ca 100 (imhos  with high quality
    distilled water.  The specific conduc-
    tance of the  sample is calculated from
    the formula:
               ADX106   ._  ,. 
          'd= R5~-
-------
                                       Use of Conductance Measurements in Water Analysis
D  Selecting Aliquot Size

    In many types of analyses,  aliquots of the
    sample must be chosen to keep the con-
    centration of reactants within definite
    limits.  Alter suitable correlations are
    established, a quick measurement of
    conductance will help in selecting the
    proper aliquot.
REFERENCES

1   Harley,  J.H. and Wiberley, S.E.,  "In-
      strumental Analysis", John Wiley &
      Sons, New York, 1954.
2   Scofield,  C. S., "Measuring the Salinity
      of Irrigation Waters and of Soil Solu-
      tions with the Wheatstone Bridge",
      U.S. Dept.  Agr. Circ. 232,  1932.

3   Wilcox, L.V.,  "The Quality of Water
      for Irrigation Use", U.S. Dept. Agr.
      Tech.  Bull.  962,  1948.

4   Wilcox, L.V.,  "Electrical Conductivity",
      JAWWA42;775, 1950.

5   Rossum,  J.R., "Conductance Method for
      Checking Accuracy of Water Analysis",
      Anal.  Chem.  2i:631,  1949.

6   Standard  Methods for the Examination of
      Water  and Wastewater, llth Edition,
      APHA, AWWA, WPCF,  1955.
                                                                                       17-5

-------
                       PRINCIPLES OF ABSORPTION SPECTROSCOPY
                                    Betty Ann Punghorst*
 I  INTRODUCTION

 In any system employing principles of
 absorption spectroscopy there are three
 basic components:

 A A SOURCE of Radiant Energy

 B A MEDIUM (Sample) which Absorbs
   Radiant Energy

 C A DETECTOR to Measure the Radiant
   Energy Transmitted by the Sample
   RADIANT ENERGY
                               DETECTOR
Figure 1.  Basic Components of Absorption
           Spectroscopy System

II   RADIANT ENERGY

A  Wave Nature

    1  The  various forms of radiant energy
      have been arranged in a single schematic
      diagram referred to as the electro-
      magnetic spectrum.   (See Figure 2.)
      All of the energies which make up this
      spectrum may be represented graphically
      as waves.  All waves move through
      space (and for most purposes,  air) at
      a constant  velocity, 3 X 101" cm/sec.

    2  Three variable characteristics of
      individual waves  serve to differentiate
      each from all other waves in the
      spectrum.
      a The Wave Length: \, the linear
        distance between the crests of two
        adjacent waves.  (Units:  distance/
        wave)

      b The Frequency:  v,  the number  of
        waves which pass a  given point in
        a unit  of time.   (Units:  waves/time
        unit)

      c The Wave Number:  v  The number
        of waves which occur in a given
        linear distance.  (Units:  waves/
        distance unit)

   3  It is evident that more  waves of short
      wave length will "fit" into a given
      linear distance  than would waves of a
      greater wave length. Thus, waves
      having short wave lengths will have
      higher wave numbers.  Mathematically
      wave length is  the reciprocal of wave
      number,  if the same units of linear
      measurement are used in each
      expression.  Since the  velocity of all
      waves is  equal and constant, it is also
      apparent  that a  greater number of
      waves of  short wave length can pass
      a given point in a unit of time than
      waves having a  longer wave length.

B  Particle Nature

   Planck conducted  certain experiments '
   which indicated that light has a particle
   as well as a wave nature.  Energy rays
   can be said to consist of particles with
   a definite amount  of energy.  These
   particles or packets are referred to as
   photons or quanta.  The energy (E) of each
   minute packet is given by  Planck's equation:
 *Chemist, DW3&PC Training Activities,  SEC.  Reviewed December 1965.

 CH. MET.al. 5a. 12. 63                                                                 18-1

-------
      Principles of Absorption Spectroscopy
                                     THE ELECTROMAGNETIC SPECTRUM
                               GENERATOR
                               60 CYCLE
                                                        t  ULTRa-
                                   Mr,.  TrS
                                   b^, -'
                                                           V OLET


                                                            *>.
                                     VE L ENG1 H    7 6 i 10 = c>

N
 T
\ 1
0
 1 I 1 1
5
f Trough
, , , 1 ,
10
, |
13
(1)
(2)
(3)
(4)
WAVE LENGTH
X
distance
wave
X (cm/ wave)
X
X
X
X
FREQUENCY
v =
waves
time
v (waves/ sec) =
CONSTANT
c
distance _ ,
time
C = (3X lolO


VELOCITY
cm/ sec)
                          Figure 3.  Relationship of Wavelength and Frequency
             E
       Where
               =   hv
                                           (5)
E  =  radiant energy in ergs

h  =  Planck's proportionality
      constant (6.6 X 10~27
      erg sec)

v  =  frequency in waves per
      second
                                             Thus it can be seen that the energy of a
                                             given photon is directly proportional to
                                             the frequency of the given radiant energy.
Ill  ABSORPTION OF ENERGY BY ATOMS
    AND MOLECULES
                                                        A Absorption of energies of given frequencies
                                                          by atoms and molecules can be used as a
         18-2

-------
                                                  Principles of Absorption Spectroscopy
 WAVELENGTH A
                           2, 000
4,000
8,000
200.,

Galon
X-rays

es per mole
needed for change
Gf:c
Ultraviolet

1*2,000

n'o
T lonization
Inner
Electron Shift



Visible Ne

71,000 35,

O-o C
ar IR Far IR

000 1,400
**" -*-^
)To O:o
Outer Vibration Rotation
Electron
Shift


         Figure 4.  Electromagnetic Spectrum Showing Energy Ranges and
           Corresponding Electronic, Vibrational and Rotational Motions
basis for their qualitative identification.
Absorption spectroscopy is based on the
principle that certain displacements of
electrons or  atoms within a molecule are
permissible according to the quantum
theory.  When radiant energy of the same
energy required to bring about this permis-
sible change  is supplied to the molecule,
the change occurs and energy is absorbed.

1  Displacement of electrons  is a permis-
   sible change which can occur when
   energy of  ultraviolet and visible frequen-
   cies strikes certain atoms and molecules.
   a Inner electron shift

     Electrons located in the inner orbit
     of an atom may,  when the proper
     frequency of radiant energy is avail-
     able, shift to an  orbit farther re-
     moved from the nucleus.  This shift
     represents  a change from a lower
     energy level to a higher one.  If
     this new position is unstable, the
     electron may revert to some  posi-
     tion nearer the nucleus; the energy
     which is thus gained may then be
     emitted from the atom as  part of its
     emission spectrum.  The  number
     of energy changes possible within
     an atom is a function of the number
     of electrons and  the number of
     changes each may enter.  Each
              possible change gives rise to a new
              spectral frequency.  Since the fre-
              quency of the radiation needed to
              accomplish such changes is of a high
              order of magnitude, the energy used
              is considerable in quantity.  Molecu-
              lar aggregations often disintegrate
              in such circumstances; thus,  these
              higher frequencies are used mainly
              for work with elements or very stable
              compounds.
           b  lonization

              Under a specific frequency of radia-
              tion,  an electron may be physically
              separated from its parent  atom.
              This process has been termed
              ionization.  A change of energy
              level of this  magnitude  requires less
              energy than the inner electron shift.
              Such  changes are characteristic of
              those of the rare earths, inorganic
              ions,  transition elements and many
              organic compounds under frequencies
              within the ultraviolet range.
            c Outer electron shift

              The various orbital electrons in an
              atom may vary in the amount of
              energy required to shift them out-
              wardly from the nucleus.  For
              example, it requires less energy to
                                                                                  18-3

-------
Principles of Absorption Spectroscopy
         shift an electron from a position
         more distant, than it does to shift
         an electron outwardly from the inner
         orbit.  Outer electron shifts occur
         readily in colored organic molecules
         for which electronic transitions are
         made easier by the presence of
         chnomophore groups which partici-
         pate in resonance.  Thus the excita-
         tion of the delocalized outer electrons
         (pi electrons) is relatively easy and
         requires energy in the visible range.
      Vibration of atoms within molecules is
      a permissible change which can occur
      when energy of near infrared frequency
      strikes certain organic molecules.

      The  atoms within a molecule are held
      together by attractive bonding forces.
      Atoms within a molecule are constantly
      moving toward and away from other
      atoms,  but for purposes of theory, can
      be said to have a certain "average"
      position.  The change in position of an
      atom in relation to another atom is
      called vibration.   The mechanics of
      vibration require energy; the manner
      and rate of vibration of the atoms
      depend upon frequencies of electro-
      magnetic radiation which strikes them.
      Therefore, a specific part of a molecule
      may absorb significant quantities of
      certain spectral frequencies. Such
      absorption will be reflected in the ab-
      sorption spectrum of the compound.
      The  energy requirements for this type
      of energy change are of a lower order
      of magnitude than those above; there-
      fore, we would expect that the fre-
      quency required would be lower and
      the wave length longer.  Such changes
      occur in organic compounds  under
      infrared radiation.
      Rotation of molecules is a permissible
      change which can occur when energy of
      far infrared frequency strikes certain
      organic molecules.

      A molecule rotates around its sym-
      metrical center.  The manner and
     rate of rotation, again, depends upon
     the energy supplied to it.  Specific
     spectral frequencies of electromagnetic
     radiation can be employed to increase
     the rate of rotation.   The used radia-
     tion is,  in effect, absorbed and is
     reflected in the absorption spectrum.

      Organic molecules utilize infrared
      radiation while varying their rate and
      manner of rotation.
B  The Lambert-Beer Law provides the
   basis for quantitative analysis by
   absorption spectroscopy.

   1  Optical density

      a  The decrease in intensity of energy
         per unit  thickness of the sample i
         proportional to the incident intensity
         of the energy and the concentration
         of the sample.
            -dl  .
             db      Klcl
                         (6)
         I

        dl
=  intensity of incident energy

=  increment of incident energy
   absorbed by sample
        db  =  increment thickness of
              absorbing solution

         c  =  concentration of absorbing
              solution

        K!  =  proportionality constant
              (varies with wavelength of
              light, the solvent  used and
              the temperature).
                                                          Integrate equation (6)
                                      db

                                     (7)
log   =  ABSORBANCE = OPTICAL
           DENSITY =  ac
  18-4

-------
                                                      Principles of Absorption Spectroscopy
a  =
          K
            1
         2.303
            =  ABSORBANCY INDEX

                               (8)
         When c is expressed in moles/1
         and b in cm,
a   =  MOLAR ABSORBANCY INDEX
 m
BOUGUER - LAMBERT LAW:
                                                 log   = ABSORBANCE = OPTICAL
                                                            DENSITY = a2bc
                                                                    2.303
Optical density is directly proportional to the
length of the path the energy must travel
within the sample.
      b  The decrease in intensity of energy
         per unit concentration of the sample
         is proportional to the incident inten-
         sity of the energy and the thickness
         of the sample.
                                            BEER'S LAW:

                                            Optical density is directly proportional to
                                            the concentration of the solute.
                                               2  Transmittance is the fraction of
                                                  radiant light energy which passes
                                                  through the absorbing solution.
           __
           dc
              K2bl
                                     (9)
T  = -L  =  10-abc
      o
(12)
        b  =  thickness of sample

       dc  =  increment concentration of
              absorbing solution
                                                  I  =  incident light energy

                                                  I  =  final light energy
              proportionality constant (varies
              with wavelength of light, the
              solvent used and the tempera-
              ture)
                                            100 X  -i-  =  PERCENT TRANSMITTANCE
                                                    o

                                           IV  SUMMARY
RANGE
Ultraviolet
Visible
Infrared
SOURCE OF
RADIANT ENERGY
Hydrogen Arc
Incandescent
Tungsten Bulb
Nernst Glower
Globar Lamp
ABSORPTION BY SAMPLE
CHEMICAL NATURE
OF SAMPLE
Inorganic Ions and
Organic Molecules
Colored Inorganic and
Organic Molecules
Organic Molecules
TYPE OF SAMPLE
CELL USED
Quartz Fluorite
Glass
Sodium Chloride or
Potassium Bromide
DETECTION OF
RADIANT ENERGY
TRANSMITTED
Photoelectric Cells
Photographic
Plates
Eye Photographic
Plates
Photoelectric Cells
Thermocouple
                                                                                        18-5

-------
Principles of Absorption Spectroscopy
REFERENCES                                   2  Mellon, M.G.  Analytical Absorption
                                                     Spectroscopy.  John Wiley & Sons, Inc.
1  Delahay,  Paul.  Instrumental Analysis.              1950.
     The MacMillan Company.  New York.
     1957.
 18-6

-------
               METAL COMPLEXES AND CHELATES IN THE COLORIMETRIC
                               DETERMINATION OF METALS

                                    James W. Mandia*
I  METAL COORDINATION COMPOUNDS

A  Metal Complexes

   1  When a metal ion combines with an
      electron donor, the resulting substance  v.~
      is said to be a complex.           AJL.^ ^  r
      Metal +  4A
                              A
                         A  M  A
                                        V
                              A
                           I
   2  In compounds such as I Co  (NHJ
      the ammonia cobalt bonds do not dis-
      sociate in solution and that the ammonia
      molecules are held firmly in definite
      positions in space about the central
      cobalt atom.
                     NH_
               H3N
                   \\/
                   /Co-NH3
                                   + 3
                                    3 Cl
      It is apparent, therefore, that the bonds
      within the  complex are covalent in
      character.

      The formation of Coordination com-
      plexes falls under the electronic theory
      of acids and bases proposed by Lewis
      (1923).

      According to this  concept neutralization
      of an acid  with a base involves the
      formation  of a coordinate bond.
      Acid    Base

      Cu+2  + 4 NH
      Ag+1 +  2 CN
                   O


                   "1
 [cu
-------
Colorimetric Determination of Metals
   Example:  The aluminum lake of Alizarin

                   O
                              1OH
D  Chelate Compounds and Color

   1  The color of chelate compounds is
      generally accepted as being so signifi-
      cant  that colors are, as a rule,  very
      carefully described in reports of these
      compounds.

   2  Absorption spectra of metal chelates
      are quite different from those of the
      organic compound and of the metal
      alone.

   3  For a given chelating agent, the wave
      lengths of the absorption maxima are
      practically independent of the  metal
      employed.  Color is due to the presence
      of the chelate ring and not character-
      istic of the particular metal in the ring.

   4  The intensity of absorption however,
      is quite sensitive to the nature of the
      metal.

E  Measurement of Intensity of Absorption -
   the Molecular Extinction Coefficient

    = Molecular Extinction Coefficient

   A = Absorbance

   b = length of cell, usually 1 cm

   C = Concentration in moles/liter usually
       1  mole/1.
                 T =
                 ^   bC~
II   METAL CHELATE COMPOUNDS IN THE
    DETERMINATION OF COPPER

 A  The Ferroin Group

    1  The reaction of 1,10-phenanthroline
      with ferrous ion yields an intensely
      red,  soluble compound called "ferroin. "

    2  The color  change from blue to red of
      the oxidation - reduction couple
      Fe(l, 10-phenanthroline) 3    
      Fe(l, 10-phenanthroline)   furnishes
      a high potential oxidation-reduction
      indicator of great utility.
                 *      *
                 O -"   v_<
                 /      \
                N        N
                //         *
               Ferroin group

 B  The Cuproine Group

    1  It was observed that the ferroin  reaction
      failed with those compounds bearing
      substituent groups on the carbon atom
      adjacent to the ring nitrogen atoms.

    2  Compounds which failed to give the
      ferroin reaction produced colors with
      cuprous copper.   These substances
      are specific for copper and are called
      the cuproine group.

                         \
          X
\
 X
              Cuproine group
       There are three cuproine reagents -
       cuproine,  neocuproine and bathocup-
       roine, and they react only with cuprous
       copper,  Cu+l.

       The copper compounds of these three
       cuproine reagents are intensely colored
       and are  soluble in certain organic
       solvents.
                                                                                      19-2

-------
                                                     Colorimetric Determination of Metals
   5  Hydroxylamine hydrochloride is usually           Bathocuproine.  Published by the G.
      chosen as the reducing agent to reduce            Frederick Smith Chemical Co. 1958.
      Cu+2 to Cu+1.
                                                 2  Standard Methods for the Examination of
      Ammonium acetate as the agent for               Water and Wastewater.  llth Edition.
      suitably buffering the solution.                    1962.

                                                 3  Martell, A.E. and Calvin, M. Chemistry
REFERENCES                                         of the Metal Chelate Compounds.
                                                      Prentice-Hall Chemistry Series.
1  Diehl, H.  and Smith, F.G.  The Copper              1953.
      Reagents, Cuproine,  Neocuproine and
                                                                                    19-3

-------
                            IRON AND MANGANESE IN WATER

                                    Betty Ann Punghorst*
I  INTRODUCTION

A  Sources*1)

   1  Nonacid ground waters

      a Iron occurs as soluble Fe(HCO3) 2-
        The colorless, clear iron-bearing
        ground water develops a turbid,
        reddish brown color upon standing
        in air due to the oxidation of
        Fe++ 	> Fe+++.

      b Manganese  occurs  as soluble
        Mn(HCO3)2.

   2  Acid surface waters

      a Iron occurs as soluble FeSO4 usually
        together with MnSO4, H2SO4 and
        A12 (SO4)3.   Acid waters generally
        do not cloud upon standing in air
        unless first neutralized.
      b  Manganese occurs as soluble
   3  Colored waters (found in the south)

      a Iron occurs in an organic chelated
        form in waters where color is due to
        the extraction of organic materials
        from decaying vegetation.  Iron in
        this form does not precipitate when
        the water is aerated.

      b Manganese occurs in a chelated form.


   4  Red waters

      Iron occurs as insoluble, suspended
      Fe(OH)3 where the metal of water
      mains, piping and tanks has corroded.


B  Effects*5^

   1  Water treatment sand filters are clogged
      and deposits of Fe(OH)3 and MnO2 are
                                                       formed on distribution pipes.  These
                                                       deposits can break loose,  be carried
                                                       down to smaller pipes or valves,  and
                                                       cause clogging and new corrosion.

                                                       Industrial use of water is affected,
                                                       (e. g., pulp and paper and textile
                                                       industries).

                                                       Domestic use of water is affected by
                                                       staining plumbing fixtures, forming
                                                       deposits on laundry,  and imparting
                                                       unpleasant colors and tastes to
                                                       beverages.
II   DETERMINATION OF IRON


 A  Collection of Sample*7)

  ^/l  Iron contamination can come from the
      flaking of rust in pipes or from a metal
      cap on the sample bottle.

    2  Colloidal iron may adhere to the sides
      of a plastic  sample bottle.
                                                 B  Methods

                                                    1   1, 10-phenanthroline*2'6'8)

                                                       a  Reaction

                                                         1) Ferric iron is reduced to ferrous
                                                            iron with hydroxylamine.
                                               4Fe
                                                   3+
     +  2NH2OH
4Fe    +
N20 +
H_O
  t
4H
                                                         2) Three molecules of 1, 10-phenan-
                                                            throline chelate one molecule of
                                                            Fe   to form an extremely stable
                                                            deep red complex, which follows
                                                            Beer's Law and exhibits maximum
                                                            absorbance at 508 m(J..
 *Chemist, DWS&PC Training Activities, SEC.

 CH. ME.fe. 5a. 11.64
                                              Reviewed December 1965.
                                                                                      20-1

-------
Iron and Manganese in Water
                                Fe
                      (2)
      b  Interferences^  '

         There are several classes of ions
         which interfere with the 1, 10-
         phenanthroline test for iron.
               1) Ions which form iron complexes
                 (e. g., phosphate,  polyphosphate,
                 CN~).   This interference can be
                 eliminated in the pretreatment
                 of the  sample by boiling with HC1.

               2) Ions which form only slightly
                 soluble complexes with 1, 10-
                 phenanthroline (e. g., Bf1"^,
                 Ag+,  Cd++, Kg"1"*",  Zn++).  This
                 interference can be reduced by
                 adding a large excess of 1,10-
                 phenanthroline.

               3) Ions whose  own color obscures
                 the phenanthroline complex color
                 (e.g., Ni++, Co++, Cr*4"*).  This
                 interference can be reduced by
                 using a blank containing an  equiva-
                 lent amount of the  interfering ion
                 present in the  sample.

               4) Oxidizing agents which  prevent
                 the complete conversion of
                             Table 1  EKPKCT OF ANIONS
                                     (All Sampler C
ON 1, 10 -PHENANTHROLINE
ontained i mg/1 iron)

Ion
Acetate
TetraboratefabBjC^
Bi omidf.
C arbonale
Chlorate
CMoride
Citrate
Cyanide
DiUiromale

Fluoride
Lodide
Nitralt-
NitriU
Oxalate
Porehloiate
Phosphate (ab P^y
Pyrophosphate

Silicate

Sullate
Sullite
fditidte
I Inotyanali
Ihiofaullalc


NaC2HjO2
tJa2B4O?
"NaBr
Na^C03
KCIOj
NaCl
C[,H807
KCN
K2Cr27

N.U.
KI
KNOj
KNO2
fNiy_,C204
K('I04
(NI^2HP04
Na4P207

NajbiOj

(Niy2b04
Na^SO.,
(Niy^i^,.
KC.NS
N*r"Ps__
Maximum
ng/1
500 0
500 0
SOO 0
500 0
500 0
1000 0
500 0
1 10 0
100 0
20 0
500 0
riOO 0
500 0
500 o
500 0
100 0
20 0
50 0
20 0
100 0
50 0
500 0
500 0
500 0
50(1 0
500 0
Maximum
% Ft-
None
None
Num.
None
None
None
None
2 0
Change hue
None
1 fa
None
None
None
None
1 2
1 4
1 0
1 0
None
None
None
None
NOIIL
Nona
None*

pll Range
20-9 0
-J 0-9 0
2090
J 0-y 0
25-90
2 0-9.0
I 0-9 0
2 0-9 0

25-90
4.0-9 0
2 0-y I)
2 0-9 0
2 5-9. 0
60-90
2 0-9 0
20-9 0
60-90
5 5-9 0
2 0-4 5
20-5 I)
2 0-9 0
20-90
1 0-9 1)
20-90
J 0-9 0
                             'i (inbuilttdruj detLimin<_d within
                             dm,ed wilti hydroxylainmu hydio
                                                        oloi d< vt lop. d ii
  20-2

-------
                                                      Iron and Manganese in Water
' Table 2. EFFECT OF CATIONS ON 1, 10 -PHENANTHROLINE TEST
(All Samples Contained 2 mg/1 Iron)
Ion Added As
Aluminum A1C13

Ammonium NH4C1
Antimony SbCl3
Arsenic As25
Arsenic AS2O3
Barium BaCln
Beryllium Be(NO3>2
Bismuth Bi(NO3)9
Cadmium Cd(NO3)2
Calcium Ca(NO3)2
Chromium Cr (SO ),
Ct 4 O
Cobalt Co(NO )
Copper Cu(NO)
J 
Lead Pb(C2H32>2
Lithium LiCl
Magnesium Mg(NO3)2
Manganese MnSO
Mercury HgC19
Mercury Hg_(NO_)_
Molybdenum (NH.J.Mo^O-.
4 o t Z4
Nickel Ni(NO,,)0
O 6
Potassium KC1
Silver AgNO
Sodium NaCl
Strontium Sr(NO )
Thorium Th(NO3>4
Tin H0SnCl .
2 6

Tin H2SnCl

Tungsten Na^WO
Uranium UOJC TTOJ0
2 2 3 22
Zinc Zn(NO3)2
Zirconium Zr(NO )

15.0 ml of o-phenanthroline in
Maximum Maximum
Concentration Interference
mg/1 % Fe
500 . 0 None
250.0 1.4
500.0 None
30.0 None
500 . 0 None
500.0 None
500.0 None
500.0 1.3
None
50.0 1.0a
500.0 None
20 . 0 None
10.0 1.5
10 . 0 None
500.0 None
500 . 0 None
500.0 None
500.0 None
1 . 0 None
10.0 None
100.0 None
2.0 None
1000.0 None
None
1000.0 None
500.0 None
250.0 1.5
20.0 None
50.0 None
10.0 None
20.0 None
10.0 Negligible
100.0 None

10.0 None
50.0 1.8
100.0 2.2
Applicable
pH Range
2.0-3.0
2.0-5.0
2.0-9.0
3.0-9.0
3.0-9.0
3.0-9.0
3.0-9.0
3.0-5.5

3.0-9.0
2.0-9.0
2.0-9.0
3.0-5. 0
2.5-4.0
2.0-9.0
2.0-9.0
2.0-9.0
2.0-9.0
2.0-9.0
3. 2-9. 0
5.5-9.0
2.5-9.0
2.0-9.0

2.0-9.0
2.0-9.0
2.0-9.0
3.0-6.0
2.5
2.0-6.0
2.0-3.0
2.5-9.0
2.0-6.0

2.0-9.0
2.0-9.0
3.0-9.0
excess of the original amount added. Iron
reduced with hydroxylamine hydrochloride in all tests.
These tables have been reproduced, with permission of Ind. and Eng.
Chemistry, 10:60 (1938), by the ~
Department of Health, Education,
and
Welfare, Public Health Service.
                                                                              20-3

-------
Iron and Manganese in Water
            Fe+++ * Fe++.  This interference
            can be reduced by adding a large
            excess of hydroxylamine.


      c  Extraction method'''

         Iron rnay be isolated from inter-
         fering ions by extracting it from
         aqueous, acid solution with di-
         isopropyl ether.  A subsequent
         aqueous extract of the iron from the
         ether is then used in the colorimetric
         determination with 1, 10-phenanthroline.


   2  2,2',  2"  - Terpyridyl (tripyridine)*4)

      Two molecules of terpyridyl chelate
      one atom of Fe   to form a reddish-
      purple complex which obeys Beer's
      Law and exhibits maximum absorbance
      at  555 ran.  Ethylenediamine  is used to
      complex all the heavy metals which
      might otherwise interfere.
Ill  DETERMINATION OF MANGANESE

 A Collection of Sample

    Acidification of sample avoids the pre-
    cipitation of MnO2 and its consequent
    adherence to the sides of the sample
    container.

 B Methods

    1  Periodate^3.6)

       a  Reaction

          1) Elimination of interferences

          2) Oxidation of Mn++
            2Mn   + 5IO
                                                                2MnO  + 5IOq  + 6H
                                                                     TC       J
    Table J  COMPARISON OF EFFECT OF DIVERSE IONS ON
      1, Ifl-PHENANTHKOLINK, NON-SFQUESTERED, AND
          SEQUESTKRKD TEHPYHIDYL METHODS
Ion

Coupe i
Cobdll
Nukcl
Zm.
Ol lliuphnspliat,.
_>_!" """l*
-------
                                                                Iron and Manganese in Water
                                     e 4  LFFFC f OF VMOVS ON THK PERIODA1 h 1 F,ST
                         Table 5. EFFECT OF CATIONS ON THE PERIODATK TEST
                              (0.4933 mg of manganese in 250 ml of solution)
Ion
Aluminum
Ammonium
Antimonous
Barium
Beryllium
Bismuth
Cadmium
Calcium
Chromic

Cobaltous

Cupric

Ferric
Ferrous
Lead
Lithium
Magnesium
Mercuric
Mercurous

Mickelous

Potassium
Silver
Sodium
Stannic
Stannous
Strontium
Thorium
Uranyl
Zinc
Zirconium
Concentration
mg/250 ml
100
100
ICO
100
50
50 (20 ml H2SO4)
100
100
50
10
50
10
50
10
100 (10 ml H.PO.)
5
100 (10 ml Iljl-i',)
100
100
100 (20 ml H2SO,)
100
50
50
10
125
100 (20 ml H2SO4)
155
50
20 (20 ml H2S04)
100
100
50 (U)
100
100
Apparent Change
In Manganese
Concentration
%
Negligible
Negligible
Negligible
Negligible
Negligible
Turbidity
Negligible
Negligible
Change in hue
Change in hue
+ IB. 1
+ 30
Change in hue
Change in hue
N.. eligible
Change in hue
Negligible
Negligible
Negligible
Negligible
- 50.7
1. 1
Change in hue
Negligible
Negligible
Negligible
Negligible
Negligible
Tut bidity
Negligible
Negligible
- 2.0
Negligible
Negligible
Approximate
Limiting
Concentration
mg/250 ml





0.0



0.0

5

5

0 0





50

10




0.0


50


These tables have been reproduced, with permission of Ind. and Eng.  Chemistry,  11: 274 (1939),
by the Department of Health, Education and Welfare, Public Health Service.
                                                                                            20-5

-------
Iron and Manganese in Water
           Correction for turbidity or inter-
           fering color can be made by
           bleaching the permanganate color
           with a reducing agent and deter-
           mining the absorption of the
           interferences.

         4) Ions which are capable of reducing
           either IOi or MnC-4 (e.g., NC>2,
           C20|. Sb*+).

           This interference can be elimi-
           nated in the pretreatment by
           boiling the sample with ^SO^
           and H3PO4.


   2  Persulfate^

      a  Reaction

         1) Elimination of interferences

         2) Oxidation of Mn"1"4"


          2Mn++ + 5S0O^ + 8H0O 	-
              2MnO   + 10SO" +  16H
      b  Interferences

         The interferences in the persulfate
         test and their removal correspond
         to those in the periodate test.  How-
         ever,  when using the persulfate test,
         HgSC>4 can be used to complex Cl~
         ion.
C Precision

   The Analytical Reference Service Water
   Metals Study of 1962 reported on a  syn-
   thetic reference sample containing
   0.25 mg/1 manganese.  93 results (per-
   sulfate method) had a standard deviation
   of + 0.100 mg/1.  57 results (periodate
   method) had a standard deviation of
   + 0. 181 mg/1.
IV SUMMARY

 The U. S. Public Health Service has set the
 recommended limits for iron and manganese
 content in finished potable waters at 0. 3 mg/1
 and 0.05 mg/1,  respectively.  Reliable
 quantitative tests for iron and manganese in
 trace  amounts are important in the following
 areas;


 A Selecting New Sources for Water Supplies

 B Determining Water Treatment Processes

 C Preventing Corrosion in Pipelines


 REFERENCES

 1 Connelley, E.J. Removal of Iron and
       Manganese. Journal of the American
       Water Works Association.  50:697-702.
       1958.

 2 Fortune,  W. B. and Mellon,  M. G.
       Determination of Iron With
       o-Phenanthroline, A Spectrophometric
       Study.  Ind. and Eng.  Chemistry.
       Analytical Edition.  10:60.   1938.

 3  Mehlig,  J.P.  Colorimetric Determina-
       tion of Manganese With Periodate,
       A Spectrophotometric Study.  Ind. and
       Eng.  Chemistry.  Analytical Edition.
       11:274.  1939.

 4  Morris, R.L.  Determination of Iron in
       Water in the Presence of Heavy  Metals.
       Analytical Chemistry.  24:1376-1378.
       1952.

 5  Riddick,  Thomas M., Lindsay, Norman L.,
       and Tomassi, Antonio.  Iron and
       Manganese in Water Supplies.  Journal
       of the American Water Works
       Association.  50:688-696.  1958.

 6  Sawyer, Clair N.  Chemistry for Sanitary
       Engineers.  McGraw-Hill Book Co.,  Inc.
       New York.  1960.
  20-6

-------
                                                           Iron and Manganese in Water
7*  Standard Methods for Examination of Water     8  Welcher,  Frank J.  Organic Analytical
     and Wastewater.  llth Ed.  APHA.                Reagents.  D. Van Nostrand Company,
     AWWA.  WPCF.  1960.                          Inc.  New York.  Ill:  1947.
                                                                                    20-7

-------
       THE DETERMINATION OF TOTAL IRON BY THE PHENANTHROLINE METHOD
                            D.  G. Ballinger and B.  A. Punghorst*
I  REAGENTS


A Hydrochloric Acid, Concentrated

B Hydroxylamine Reagent, 10% Solution

   Dissolve 10 g NH2OH. HC1 m 100 ml
   distilled water.


C Ammonium Acetate Buffer Solution

   Dissolve 250 g NH4C2H3O2 m, 150 ml
   distilled water.  Add 700 ml glacial acetic
   acid and dilute to a liter.


D Iron Stock Solution
   Add 20 ml concentrated H2SO4 to 50 ml
   distilled water and dissolve 0.7022 g
   Fe(NH4)2 (SO4)2- 6H2O.  Add dropwise
   0. IN  KMnO4 until a faint pink  color
   persists.  Dilute to a liter. This solution
   contains 0. 10  mg Fe per ml.

E  Iron Working Standard

   Pipette 100 ml ironstock solution into
   1 liter flask and dilute to mark with
   distilled water.
1
ml
= 0.
010
mg
Fe
F  Phenanthroline Solution

   Dissolve 0.1  g 1, 10-phenanthroline mono-
   hydrate,  C12HgN2-H2O,  in 100 ml distilled
   water by stirring and heating to 80C;  do
   not boil.  Discard the solution if it darkens.
   (Note that 1 ml of this reagent is sufficient
   for no more than 0. 1  mg Fe).
 G  Working Solutions

    1  Reducing reagent  - one part NH2OH
      added to two parts cone. HC1.

    2  Color reagent - ten parts acetate
      buffer added to four parts phenanthroline.

      Note: The working solutions should be
            made up daily.

II   PROCEDURE

 All glassware should be prerinsed with cone.
 HC1.

 A  Take an aliquot of sample containing
    0.01 - 0. 1 mg Fe.  Dilute to 50 ml  in
    Erlenmeyer flask.  Treat 0.0, 1.0, 2.0,
    4. 0,  8.0,  and 10 ml of iron working
    standard in the same manner.

 B  Add 3 ml of reducing reagent.  Boil on a
    hot plate until volume reaches about 20 ml
    (35 minutes).

 C  Cool.  Add to 50 ml rough calibrated
    Nessler tube  containing 14 ml.  color
    reagent.  Dilute to 50 ml.  Mix thoroughly.

 D  After 15 minutes, read absorbance  on
    spectrophotometer using  1 cm cells at
    510  m|j. and setting reagent blank at
    0  absorbance.

 E  Plot concentration of Fe vs. absorbancy.

 F  Determine absorbance of unknown sample
    and  calculate concentration of  sample
    from standard curve.
 *In Charge,  Chemistry, Technical Advisory and Investigations Section, DWS&PC,  and Chemist,
 DWS&PC Training Activities,  SEC.  Reviewed December 1965.
 CH. ME. FE. mn. la. 11. 64
                                                                                      20-8

-------
            THE DETERMINATION OF MANGANESE BY PERIODATE OXIDATION

                            D. G. Ballinger and B.  A. Punghorst*
 I   REAGENTS


 A  Sulfuric Acid,  Concentrated

 B  Nitric Acid,  Concentrated

 C  Phosphoric Acid,  85% Solution

 D  Potassium Metaperiodate, KIO.

 E  Silver Nitrate

 F  Manganous Standard

    1  Dissolve 3. 2 g KMnO4 distilled water
      and make up to a liter.

    2  Heat solution for several hours near
      the boiling point.

    3  Filter through fritted glass filter.

    4  Standardize against sodium oxalate.


 G  Manganous Working Solution

    Calculate the volume of manganous stand-
    ard (F) to dilute to 1 liter so that 1.0 ml
    -  0.05 mg Mn.  To this volume add
    2-3 ml cone. H2SO4  + NaHSO3 until the
    permanganate color disappears; boil to
    remove excess SO2.  Dilute to 1 liter.


II   PROCEDURE


 A  Prepare manganese standards by pipetting
    0.0, 1.0, 2.0,  4.0, 6.0  ml of manganous
    working  solution (I-G) into 125 ml
    Erlenmeyer flasks. To the sample flask
    add an aliquot of sample  containing 0.05 mg
    Mn - 0. 30 mg Mn.
  B Add 5 ml concentrated H2SO4 and 5 ml
    concentrated HNOg.  Evaporate to SOg
    fumes.

  C Cool.  Cautiously add 85 ml distilled
    water.  Cool again.  Add 5 ml HNO3
    and 5 ml H3PO4.  Mix.

  D Add 0. 3 g KIO4 and 20 mg AgNO3.

  E Heat to boiling and keep at slightly below
    boiling point for 10 min.  or at least an
    hour for  small amounts of Mn.

  F Cool and dilute to 100 ml in Nessler tubes.
Ill  CALCULATIONS


 A Prepare standard curve with mg Mn vs.
    absorbancy at 525 m(j..

 B Determine absorbance of unknown sample.

 C Calculate mg Mn in unknown from standard
    curve.
 REFERENCE

 1  Standard Methods for Examination of
       Water and Wastewater.  llth Ed.
       APHA.  AWWA.  WPCF.  1960.
  *In Charge, Chemistry, Technical Advisory and Investigations Section, DWS&PC, and Chemist,
  DWS&PC Training Activities, SEC. Reviewed December 1965.
  CH. ME. mm. 3. 11. 64
                                      20-9

-------
                        PRINCIPLES OF EMISSION SPECTROSCOPY

                                      J. F. Kopp*      ^
I  INTRODUCTION
The term "spectroscopy, " in its broadest
sense, refers to the study of the radiations
of the electromagnetic spectrum.  As no
single instrument exists which will separate
radiation from all parts of the spectrum, it
is divided into regions which are related to
the different types of instruments capable of
producing or measuring waves of various
lengths.  A diagram of the spectral dis-
tribution of energy is shown in Figure 1.
Emission spectroscopy is concerned with that
region wherein radiation can be  sorted out
into a spectrum by means of prisms or grat-
ings,  and includes the near infra-red, the
visible and the ultraviolet.
Emission spectroscopy has become an indis-
pensable part of  the  modern chemist's
analytical methods.  With it he can analyze
a wide variety of substances both qualitatively
and quantitatively for trace elements regard-
less of valence states.
                            II  THEORY

                             A Origin of Spectra - Excited atoms and
                               atomic ions emit light of definite wave-
                               lengths.  The excitation of multiple
                               elements in a sample results in the simul-
                               taneous production of the spectra of all of
                               these elements.

                               During excitation by a thermal or electri-
                               cal source,  the outer orbital electrons of
                               an element absorb energy and rise to
                               higher energy levels.  These electrons
                               then return  spontaneously to their normal
                               or ground states by a single jump or by a
                               series of jumps.  The energy emitted
                               with each jump produces a spectral line
                               of characteristic wavelength and frequency
                               for the particular chemical element.  The
                               combination of lines produced by the
                               excited atoms of the element thus provides
                               the emission spectrum of that element.
                                       FIGURE 1
                          SPECTRAL DISTRIBUTION OF ENERGY
                                                  A  R
    x 10*   10*    to4   ioz   10   10-2   10-*    i  i  10-*   lo-10   icr2  METERS
       L   i	L  1   l   A   *   l	All  j   i   .   I.  ll   I   i   I   i   i
1
10' 3 5 7i '
 RADIO -j

11 13
1 INFRA-
r RED"*
I
ULTRA? "
VlOLEl
 ULTRA SONIC -
                                                                          PERSEC
                           I    S\         | GAMMA | COSMIC
	 HERTZIAN WAVES	1  /   \       |*~ RAYS J  RAYS~~
                           h-VISIBLE-}

                                    |X-RAYSj
                 IINFIjAREDj VISIBLE  j
  WAVELENGTH X  1500 75060<)5004bo   300 250     200

                  REGION INCLUDED IN IMIIIIOMTIKCTROSCOPY
                                                 B
                                                '.m^- METERS x 10"
                                                     10 ANGSTROMS
 *Spectrochemist, Water Pollution Surveillance System,  SEC.  Reviewed December 1965.

 CH.MET.es.1.5.65                                                                 21'1

-------
Principles of Emission Spectroscopy
 B Types of Spectra

   There are three types of emission spectra:

   1  the line spectra produced by highly
      excited atoms or atomic ions;

   2  band spectra which originate with
      highly excited molecules;

   3  continuous spectra which result when
      light is emitted by incadescent solids.


Ill  INSTRUMENTATION

 The emission spectrograph consists of
 essentially four distinct functional parts,
 the excitation source, the  slit, the  optical
 system and the recording system.  A diagram
 of a  Littrow type spectrograph is shown
 in Figure 2.
A  The production of line spectra for the
   detection or the determination of the
   elemental constituents in a sample, re-
   quires an excitation source such as an
   arc, a spark or a flame.

B  The slit of a spectrograph permits only
   a narrow beam of light of mixed wave-
   lengths to enter the instrument.

C  The optical system consists of a series of
   lenses and either a prism or a grating, to
   separate light rays of different wave-
   lengths into the spectrum.

D  The recording system can be either;

   1  an eye piece as ie used in a spectro-
      scope,

   2  a photographic plate  as is used in a
      spectrograph, or
                                     FIGURE 2
            SCHEMATIC DIAGRAM OF A
              LITTROW SPECTROGRAPH
                     EXCITATION
                       SOURCE
                                                              SLIT i
                             COLLIMATOR-
                             CAMERA LENS
  MIRRORED
    BACK
                                                                           TOTAL
                                                                        REFLECTING
                                                                           PRISM
           30-60-90*
         QUARTZ PRISM
                                                                     CAMERA
   21-2

-------
                                                      Principles of Emission Spectroscopy
IV
          a photoelectric cell as is used in
          the direct reading spectrograph.
SELECTION OF EQUIPMENT AND
COST CONSIDERATIONS
 A decision concerning the advisability of
 installing a laboratory for spectrochemical
 analysis,  whether in an industrial plant,
 research  laboratory or state health depart-
 ment might rest upon four main considerations:
 A Whether the analytical problems encounter-
    ed have no satisfactory solution apart from
    spectroscopy,

 B The time urgency of the work,

 C The expected volume and diversity of
    work,

 D The cost of the initial investment, to-
    gether with operating expenses.
V  PROBLEMS AND TECHNIQUES
   ASSOCIATED WITH EMISSION
   SPECTROSCOPY

After the equipment has been set up properly
and is ready for operation there are many
parameters to be determined before the first
samples are analyzed.
                                              A  Source - arc or spark

                                                 There are several types of excitation
                                                 sources available as are shown in Table I.
                                                 Both the type  of sample and the precision
                                                 and accuracy required for the analysis
                                                 will generally govern which type of
                                                 excitation method should be employed.

                                              B  Type of Electrode

                                                 The spectrographic  electrode plays  an
                                                 important part in the analysis.  Some
                                                 important features are:
                             TABLE 1.  EXCITATION SOURCES
TYPE
D. C. Arc
High Voltage
A.C. Spark
Low Voltage
A. C. Arc
Spark Ignited
Uni - Arc
High Voltage
A. C. Arc
PRECISION
Fair
Excellent
Good
Good
Fair
SENSITIVITY
Excellent
Fair
Good
Good
Excellent
RANGE
0.00001 -
1, 00%
0.01-30.0%
0.001 - 1.0%
0.001 - 1.0%
0.00001 -
1.0%
USE
Basic source for general
qualitative analysis - soils,
ores, oxides, slags, ashes,
etc. Highest sensitivity of
detection for trace elements.
Most stable. Use for alloy-
ing constituents in metals.
Solution techniques.
Quantitative determination
of residual impurities low
alloying constituents in
metals.
Combines precision of the
spark and the sensitivity of
the D. C. Arc.
Steadier than D. C, Arc -
Conductors and nonrefrac-
tory materials.
                                                                                        21-3

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Principles of Emission Spectroscopy
      Density - the current and temperature
      obtainable are dependent on the density
      of the graphite.

      Shape - the nature of the sample being
      analyzed will usually determine the
      shape and type of electrode.

      Purity - trace analysis requires that
      the electrodes be of very high purity.
C  Exposure  Conditions

   Current,  voltage, exposure time, etc.,
   all play an important part.
D  Type of Photographic Plate

   The photographic emulsion most generally
   used for quantitative analysis is the S. A.
   #1.  This emulsion responds to the
   spectral range from 2400 to 4400  A.   It
   has high contrast,  low background density
   and low granularity.

   The S. A. #2 emulsion is also desirable
   for trace analysis  when lower contrast,
   higher  speed and wider latitude are
   needed. S.A.#2 also covers the range
   from 2400 to 4400 A.  Other photographic
   emulsions, covering the wavelength range
   from 2400 to 12000 A, are available,  each
   having  specific features. Processing of
   these photographic plates is extremely
   important  and directions of the  manu-
   facturer should be closely followed.
E  Qualitative Analysis

   In spectroscopy, qualitative analysis
   is a relatively simple process although it
   can be more time consuming than a
   quantitative determination, especially if
   a complete qualitative analysis is re-
   quired.  The presence or absence of over
   60  of the chemical elements can be  readily
   determined by a simple  inspection of the
   resulting pattern of spectral lines.  All
   elements give  specific lines when
   sufficiently excited, which is the basis of
   qualitative spectrochemical analysis.
 F Quantitative Analysis

    Quantitative spectrochemical analysis
    is based on the fact that the amount of
    light emitted by an element present at
    very low concentrations is directly pro-
    portional to the number of its excited
    atoms present, if all other factors are
    kept constant.  The intensity of the
    spectral line of the analysis element
    (or degree of blackening of the  photo-
    graphed image of the line) in an unknown
    sample  is compared with  the intensity
    of the corresponding line  in a standard
    sample  to provide an estimation of the
    concentration of the element producing
    that line.
 G Internal Standard

    In quantitative analysis the errors caused
    by temperature fluctuations and wandering
    of the arc are minimized by the use of the
    internal standard technique.  This consists
    of comparing the intensity of a suitable
    line of the analysis element in the standard
    and in the unknown sample to a certain
    selected line of another element whose
    concentration is fixed in all samples.

    As both the unknown and the internal
    standard are a part of the same sample,
    variations in the time of exposure,  plate
    characteristics and developing conditions
    will not affect the relative density of the
    two lines which are equal in intensity in
    the light source.

    Working curves  are established by plotting
    the intensity ratio of the analysis line to
    the internal standard line versus the con-
    centration of the analysis element.
VI  APPLICATION OF EMISSION SPECTRO-
    SCOPY TO WATER ANALYSES

 Trace elements in water originate from a
 variety of sources but can be classified into
 three principal groups:

 A Elements contributed by soluble materials
    chemically weathered from  soil and rocks.
 21-4

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                                                       Principles of Emission Spectroscopy
B  Elements that are selectively concentrated
   by vegetation and find their way to surface
   waters following decay and run-off.

C  Industrial sources,  especially those de-
   voted to mining,  alloying, and cleaning and
   plating of metals.

   These sources may contribute significant
   quantities of trace elements to surface
   waters both in populated and unpopulated
   areas.  The  detection and measurement
of these trace elements is difficult with
conventional analytical procedures because
they are not adapted to large numbers of
samples and in some cases are not sensi-
tive enough.  The use of a spectrographic
procedure,  however, for routine moni-
toring of raw waters is admirably suited
to the purpose since a large number of
elements may be determined simultaneously
with excellent accuracy.  Table 2 lists
those elements routinely looked for and
their concentration ranges.
              TABLE 2.  WAVELENGTHS AND CONCENTRATION RANGES OF
             ELEMENTS ADDED TO SYNTHETIC WATER MATRIX MATERIAL
Element
Cadmium
Barium
Beryllium
Lead (high)
Lead (low)
Chromium
Tin
Antimony
Manganese
Iron
Nickel
Bismuth
Molybdenum
Vanadium
Copper
Zinc
Cobalt
Silver
Wavelength, A
2280.0
2335.3
2348.6
2663.2
2833. 1
2677.2
2840.0
2877.9
2933. 1
2973.2
3003.6
3067.7
3170.3
3183.4
3274.0
3345.0
3453.5
3280.7
Micrograms per
Electrode Con-
centration Range
0.03 - 1.0
0.02 - 10.0
0.0005 - 0. 1
0.05 - 10.
0.05 - 1.0
0.01 - 1.0
0.02 - 1.0
0.1 - 1.0
0.04 - 1.0
0.02 - 1.0
0.02 - 1.0
0.05 - 0.1
0.02 - 0.1
0.02 - 1.0
0.003 - 1.0
5.0 - 10.0
0.02 - 1.0
0.0005 - 0.05
                                                                                      21-5

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   Principles of Emission Spectroscopy
     Trace elements, whether in raw or
     finished water, are generally present in
     concentrations too low to measure directly
     with the spectrograph.  A means of con-
     centration, therefore,  is necessary before
     the  examination can be completed.  This
     can be accomplished in several ways,  i.e.,
     evaporation,  precipitation, ion exchange,
     etc.
VII  PREPARATION OF STANDARDS

  As the major constitutents of a sample are
  important factors that affect the burning
  qualities of the arc and the intensities of
  resulting spectral lines, it is important that
  the composition of the standard matrix ma-
  terial approximate the samples as closely
  as possible.  This is accomplished by pre-
  paring a synthetic matrix to  approximate  the
  average composition of waters of North
  America as given by F. W.  Clarke (see
  references) and consists of 20% calcium,  5%
  magnesium, 7. 5% sodium and 2% potassium.

  The nitrates of these elements are combined
  in a single solution using double distilled
  water and to this synthetic matrix are added
  increasing amounts  of the analysis elements
  over the concentration range.
VIII  ACCURACY

   The average error in quantitative emission
   spectroscopy using the photographic process
   is generally between + 5 -  10%.  In the direct
   reading process,  however, where photo-
   multiplier tubes are  substituted for the
   photographic plate,  an average error of
   + 2% is possible.  This  accuracy is more
   than satisfactory  considering that determi-
   nations of trace elements are being made in
   the parts per billion  range.

   A Water Pollution Surveillance System Results

      The spectrographic measurement of
     trace metals in surface  waters of the
      United States has  been performed routinely
     by the System since  1958.  Approximate
     levels of detection for various water
     systems are shown in Table 3.
      Of the 17 elements included in the spectro-
      graphic examination of those major water
      systems shown (during the years 1958 -
      1962), antimony, beryllium, bismuth,
      cadmium,  cobalt, tin and zinc were
      either detected infrequently or not at all.
      The frequency of detection for other
      elements is shown  in Table 4.
  It should be emphasized that in quantitative
  spectrographic analysis the best possible
  standards must always be prepared.  A good
  spectrographer is only as good  as his
  analyses and his  analyses are only as good
  as his standards.  Spectrographic standard
  solutions are prepared from Reagent Grade
  chemicals.  The  oxides are preferred where
  possible; however, the nitrates or chlorides
  will usually suffice.  Occasionally, it is
  necessary to use special spectroscopically
  pure grades of certain metals.  Nitric  and
  hydrochloric acids should be re-distilled,
  and double distilled water is also suggested
  where possible.  Borosilicate glassware,
  cleaned with both chromic and nitric  acids,
  is used throughout.
   B Analytical Reference Service Results

      A sample containing eight trace metals at
      concentrations shown in Table 5  was
      analyzed by sixty-six participating agencies
      using a number of analytical methods.  The
      mean results of all sixty-six laboratories
      in addition to those laboratories employing
      spectrographic procedures are shown in
      Table V.  It is apparent from this summary
      that the spectrograph can be used to
      splendid advantage on water  samples.
     21-6

-------
                                     Principles of Emission Spectroscopy
     TABLE 3.  APPROXIMATE LEVELS OF DETECTION
         ACHIEVED FOR VARIOUS WATER SYSTEMS
                           (tig/D
Group
I Ag, Be
II Ba, Cr,
Cu, Fe,
Mn, Mo,
Ni, Pb, V
Cd, Co, Sn
m Bi, Sb
IV Zn
Colorado
0.3-0.5
2-20
30 - 60
2500 - 3500
Columbia
O.Q3 - 0.05
1-5
5-10
300 - 500
Great Lakes
0.05 - 0. 1
1-5
5-10
400 - 600
Ohio
0.05 - 0. 1
1 - 10
10 - 20
600 - 800
Mississippi
0. 1 - .2
2-20
20 - 30
800 - 1000
Missouri
0. 1 - 0.2
1 - 10
20 - 40
1500 - 2500
TABLE 4. FREQUENCY OF DETECTION OF TRACE ELEMENTS
               IN CERTAIN WATER SYSTEMS
                       (1958 - 1962)

SYSTEM
Colorado River
Columbia River
Great Lakes
Mississippi River
Missouri River
Ohio River
Average
ELEMENT %
Ba
79
94
95
100
96
94
93
Cr
12
87
32
23
10
20
31
Cu
61
100
98
96
85
91
89
Fe
82
100
98
95
92
100
95
Mn
0
13
4
11
6
17
9
Mo
82
90
50
68
65
37
65
Ni
9
48
39
23
8
31
26
Pb
6
29
20
11
3
11
13
V
9
3
0
0
2
0
2
Ag
0
0
14
12
57
60
24
                                                                   21-7

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Principles of Emission Spectroscopy
          TABLE 5.  SUMMARY OF RESULTS OBTAINED BY SPECTROGRAPHIC
                 PROCEDURES ON ARS SAMPLE; WATER METALS, NO. 2
Element
Al
Cr
Cu
Fe
Mn
Cd
Zn
Pb
Amount Added
mg/1
1.80
0. 18
0.42
0.62**
0.25
0.24
0.90
0. 18
Mean of
66 Labs
2.21
0. 14
0.43
0.44
0.28
0.26
0.94
0.20
AMOUNT RECOVERED mg/1
Lab #71126
1.8
0. 18
0.29
0.46
0.25
0.25*
0.68
0.27
NWQN Lab
2.30
0. 13
0.38
0.40
0.23
0.30
0.94
0. 19
Lab #1615
3. 10
0. 17
0.41
0.75
0.38
0.50
0.88
-
           This result was erroneously included under Lab #7112 A in the ARS report.
         **
           Iron value was adjusted to mean value as suggested on page 47 of ARS report.
   SUMMARY

The theory and instrumentation of emission
spectroscopy are presented.  Consideration
is given to the problems  and techniques
associated with trace element analysis in
water using the emission spectrograph.
REFERENCES

Emission Spectroscopy

1  Nachtrieb, Norman H.  "Principles and
     Practice of Spectrochemical Analysis. "
     McGraw-Hill Book Co.,  Inc.  1950.

2  Clark, George L.  "The Encyclopedia of
     Spectroscopy. "  Reinhold Publishing
     Corp.   1960.
Water
   Kroner,  Robert C.,  and Kopp,  John F.
     "The Occurrence and Significance of
     Trace  Elements in Surface Waters. "
     Presented at the Meeting of the Iowa
     Section. American Water Works
     Association,  Sioux City, Iowa.  Oct.
     16-18, 1963.

   Kopp,  John F.,  and Kroner,  Robert C.
     "A Direct Reading Spectrochemical
     Procedure for the Measurement of
     Nineteen Minor Elements in Natural
     Water. "  In Press.

   "National Water Quality Network,  Annual
     Computation of Data. " 1960-1961. U. S.
     Dept. of Health, Education and Welfare,
     Public Health Service Publication,
     No. 663.
  21-8

-------
                                                   Principles of Emission Spectroscopy
Haffty, Joseph  "Residue Method for
   Common Minor Elements. " U.S.
   Dept.  of Interior, Geological Survey,
   Water Supply Paper,  No.  1540 A.  1960.

Silvey, W. D., and Brennan R.  "Concen-
   tration Method for Spectrochemical
   Determination  of Seventeen Minor
   Elements in  Natural Water. "  Anal.
   Chem.,  34,  784. 1962.
Skougstad,  M.W., and Horr, C.A.
   Occurrence and Distribution of
   Strontium in Natural Water. " U.S.
   Geological Survey, Water Supply Paper
   No. 1496 C.  1963.

Clarke, F. W.   "The Composition of the
   River and Lake Waters of the United
   States."  U.S. Geological Survey,
   Papers No. 135.  1924.
                                                                                 21-9

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                   THE POLAROGRAPHIC DETERMINATION OF COPPER,
                               CADMIUM, NICKEL, AND ZINC

                                       C. E. Stephan*
 I  SOURCES AND SIGNIFICANCE
 A  Sources
                                 (1)
    All are produced in mining and refining of
    ore and manufacture of the metals and
    alloys. All are found in metal plating
    wastes.   In addition, copper salts are
    used  as algicides.

 B  Significance

    All can interfere to some extent with the
    efficient operation of sewage treatment
    plants. *  All can produce undesirable
    taste in drinking water, and cadmium is
    very  toxic to humans.    Individually
    copper, cadmium, and zinc are  toxic to
    many forms of aquatic life  at a concentra-
    tion of 1 mg/liter (1 ppm),  whereas
    nickel can often be tolerated at the 10 mg/
    liter  level.  But there have been many
    reports that combinations of the metals
    are more toxic.

II   FACTORS INFLUENCING THE CHOICE
    OF AN ANALYTICAL METHOD*5' 6 7)

 A  Sensitivity

 B  Accuracy and Reproducibility

 C  Expense of Equipment and Reagents

 D  Time Requirements

 E  Sensitivity to Interferences and Ease of
    Removal of Interferences

 F  Specificity

 G  Simultaneous Determination of Several
    Substances
III  SAMPLE PREPARATION

 A Total, Dissolved, or Reactive Metal

 B Removal of Interferences

    1  Organic
                        rfJJ >
       a  Wet ashing(8)  r*~'">i

       b  Dry ashing  ;, ' - '~''f "

          1)  High temp. <9> 10> n>

          2)  Low temp. *12)

    2  Inorganic

       a  Solvent extraction

       b  Complexation

       c  Electrolysis

       d  Ion-exchange


IV  CHOICE OF ELECTROLYTE*13'  14)

 A Well-Formed Waves

 B Separation of Waves

 C Removal of Oxygen

 D Electrolytes Used

                         (15)
    1  Ballinger-Hartlage

        2.  ml cone. HC1
       10.  ml distilled H2O
        8.  ml cone. NH4OH
        0.5 ml 0. 2% Triton X-100

       20. 5 ml + 0. 5 g Na2SO3
71'
 *Chemist, Aquatic Biology Section, Basic and Applied Sciences Branch,  DWSPC, SEC.

 CH. ME. lla. 12. 65                                                                     22-1

-------
polarographic Determination
           (16)
   2  Mount

       50 ml cone. HC1
      200 ml cone. NH4OH
       40 ml 0. 04% Triton X-100
      210 ml distilled H2O

      500 ml + Na2SO3

   3  Sirois(17)

      1. 0 M. NH4OH
      1.0 M. NH4C1
      0. 1 M. Na2SO3
      0. 01 % Gelatin in H2O (""-*
   4  Stephan
             (18)
 10    ml cone. HC1
 40    ml cone. NH4OH
       g Na2SO3
   . 05 g Gelatin
       10
      450     ml H2O
500
             ml
                         ^
V  ANALYTICAL PROCEDURES

                          (19)
A  Sewage Samples for Zinc

   1  Weigh sample into 50 ml beaker and
      evaporate to dryness.

   2  Add 5  ml HNOg and 2 ml H2SO4 and
      boil to dryness (Use HC1O4 on resis-
      tant samples).

   3  Add electrolyte no. 2.  Filter.

   4  Run polarogram.

B  Tissue Samples for Cadmium and
   Zinc<16'W

   1  Weigh tissue in crucible.

   2  Ash for 4 hours at-oOC.

   3  Dissolve ash in acid.

   4  Separate cadmium and zinc on ion
      exchange columns.

   5  Evaporate  to dryness.
   6  Add electrolyte no. 2 and run      *
      polarogram.
                                    (17  21
C  Plant samples for Copper and Zinc   '

   1  Weigh sample in beaker

   2  Ash at 500C for 4 hours.

   3  Add hydrochloric acid and boil to
      dryness.

   4  Add electrolyte no. 3. Filter.

   5  Run polarogram.

D  Water Samples for Copper, Cadmium,
   Nickel,  and Zinc*  '

   1  Place aliquot in beaker and acidify.

   2  Evaporate to dryness.

   3  Ash, add HC1,  and boil to dryness,
      if necessary.

   4  Add electrolyte no. 4.

   5  Transfer to 10 ml beaker.

   6  Run polarogram.


REFERENCES

1  Kroner, R. C. and Kopp, J. F.  JAWWA
      57: 150.  1965.

2  Earth,  E. F.   et al.  JWPCF 37: 86.  196:

3  PHS Drinking Water Standards.  PHS
      Publication No. 956.   1962.

4  Water Quality Criteria.   Publication No.
      3-A, Resources Agency of California.
      1963.

5  Margerum, D. W.  and Santacana, F.
      Anal. Chem. 32: 1157. 1960.

6  Kroner, R. C.  et al.  JAWWA 52: 117.
      1960.

7  O'Connor, J. T. and Renn,  C.E.  JAWW/
      55:631.  1963.
22-2

-------
                                                               Polarographic Determination
 8  Smith,  G.F.  Talanta  11: 633.  1964.

 9  Pijck,  J.  et al.  Internal.  J.  Appl.
       Radiation Isotopes 10: 149. 1961.

10  Alexander, G. V.  Anal. Chem.  34: 951.
       1962.

11  Gorsuch, T.T.  Analyst  87:  112.  1962.

12  Low Temperature Dry Asher, Tracerlab,
       2030 Wright  Avenue, Richmond, Calif.

13  Bush, E.L.  and Workman, E.J.  Analyst
       90: 346.  1965.

14  DuBois, L. and Monkman,  J. L.   Am.
       Ind.  Hygiene Assoc. J. 25: 485. 1964.
15  Ballinger, D. G. and Hartlage,  T.A.
       Water and Sewage Works.  109: 338.
       1962.

16  Mount, D. L  Trans. Amer. Fisheries
       Soc.  93: 174.  1964.

17  Sirois, J. C.  Analyst.  87: 900.  1962.

18  Stephan,  C.E.  Unpublished.

19  McDermott, G. N.   et al.  Ind.  Waste
       Conf.  Purdue Univ. Ext. Ser.  112:
       461.  1962.

20  Mount, D.I. and Stephan, C. E. Unpublished.

21  Robertson, G.  Analyst.  89: 368. 1964.

-------
                            THE DETERMINATION OF PHENOLS

                                        J. W. Mandia*
 I   DEFINITION AND SIGNIFICANCE
 A  Definition

    The phenolic compounds in water chemistry
    collectively referred to as phenols are
    defined as those hydroxy derivatives of
    benzene,  or its condensed nuclei, which
    can be determined colorimetrically by the
    aminoantipyrine or Gibbs method.
       All chlorination products may contribute
       to the intensity of taste and odor.

       At maximum taste and odor intensity
       the major contributor is a  hitherto
       overlooked compound 2, 6-dichlorophenol.

       The chlorine-to-phenol ratio at maximum
       intensity of taste and odor  is 2:1.  The
       proportion of 2, 6-DCP  was greatest at
       the 2:1 chlorine-to-phenol  ratio.
 B  Significance

    Phenol and chlorinated derivatives in
    water affect fish and water quality.

    1  Fish

      The threshold limit of toxicity at
      infinite time for certain species of
      fish is of the order of a few milligrams
      per liter.  Some  chlorinated phenols
      exhibit  toxicity in concentrations as
      low as 0. 2 mg/1.
    2  Fish flesh tainting

       Fish living in waters of lesser
       phenolic concentration  can acquire
       an unpleasant and obnoxious taste.
Ill  STANDARDIZATION OF PHENOL -
    Bromate-bromide Method
 A Reaction
                    6HC1
  2KBrO3 + 2KBr	^  2Br2 + 4KC1 + 3H2O

                                  OH
  3Br
u   +
3HBr
                                                                                  Br
  B Calculations

    Equivalent wt of phenol =
    3  Water quality

      The presence of as little as 1 ng/1 of
      the chlorinated phenols can impart a
      taste to drinking water.
                                                           atomic wt of phenol
 atoms of Br /molecule of unreacted phenol
             1
             94. 11
                    = 15.685 eq.  wt.
II   CHLORINE DERIVATIVES OF PHENOL
    CAUSING TASTE AND ODOR
 A  Progressive Chlorination of Phenols

    2- and 4- CP: 2,4 dichlorophenol,
    2, 4, 6 trichlorophenol and 4, 4
    dichloroquinone, 2, 6 dichlorophenol
    1 ml of 0. IN bromate-bromide  =  0.1
    millequivalent (meq)

    Meq X' equivalent wt  =  milligrams (mg)

    0. IN bromate-bromide  = 0.1 X  15.685
    or 1. 5685 mg of phenol
*Chemist, DWS&PC Training Activities, SEC.  Reviewed December 1965.

CH.PHEN. 32a. 12. 63                                                                    23-1

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The Determination of Phenols
   1 ml of 0. IN bromate -bromide = 4 ml of
   0. 025N thiosulfate;

   1 ml of 0.025N thiosulfate  = 1.5685/4
   = 0. 3923 mg of phenol

   (AB-C) =  amount of brominating agent
             consumed by the sample,
             expressed as ml of 0. 0 25N
             thiosulfate.

       A  =  ml of 0. 025N thiosulfate for
             each 10 ml portion of bromate -
             bromide reagent,  used for the
             blank.

       B  =  No. of 10 ml portions of the
             bromate-bromide reagent used
             for the blank.

       C  =  ml of 0. 025N thiosulfate used
             to titrate the excess brominating
             reagent in the sample.

    For a determination based on 50 ml of
    sample, mg phenol/50 ml of sample
    = (AB - 0(0. 3923)
           impurities.  The rate of volatilization of    
           the phenols is gradual, so that the volume
           of the distillate must equal that of the sample
           being distilled.

           A Reagents

             1  Copper sulfate

                CuSC>4 forms CuS thus preventing the
                formation of H^S which interferes with
                the determination.  It also prevents
                biochemical degradation.


             2  Phosphoric acid

                Acidification of the sample with
                H3PO4 assures the presence of the
                copper ion.
          B Interferences

             Oxidizing agents as detected by the starch-
             iodide test,  are removed immediately
             after  sampling by the addition of an excess
             of ferrous sulfate or sodium arsenite.
     mg Phen01     = (AB- 0(0. 3923) (10)
    liter of sample
50
          V THE 4-AMINO ANTIPYRINE METHOD
                   = (AB - C)(7.846)
                                                 A  Procedure
IV  PHENOL DISTILLATION

 Phenols are distilled at more or less
 constant rate from the nonvolatile
             Purified phenols but not paracresol react
             with 4-amino antipyrine at a pH of 10.0
             in the presence of ferricyanide to form
             an antipyrine dye.  The dye is extracted
             from aqueous  solution with chloroform
             and the absorbance read at 460 m|J..
      Reaction
 CH3-N
 CH3-C  =  C-NH2
                                        pH - 10
                                      K-Fe (CN)
                                        3        6
                             OH
                  CHQ-N     C=0
                     o
                  CH  -C  =  C-N
                     O
                         RED
                                                                                         =  O
 23-2

-------
                                                            The Determination of Phenols
      The reagent 4-aminoantipyrine reacts
      with phenols in the presence of an
      oxidizing agent to form a colored
      compound sensitive to a few ppb.

      With all of the simple phenols  the
      reaction product is the same color
      (red) although the response with
      different phenols varies.  Phenol,
      CgHgOH is  most sensitive and all
      results are customarily reported in
      terms of CgHgOH.

      The reaction product is soluble in
      chlorinated hydrocarbons.  Chloroform
      is the  solvent of choice by reason of
      extraction efficiency,  stability, cost,
      toxicity,  etc.
B  The Variables in the 4 AAP, Amino
   Antipyrine Method

   1   The reaction is carried out at pH  10
      to minimize interference from aniline
      and other aromatic amines.

   2   Time of color formation is not a
      variable since the reaction takes place
      immediately.

   3   The reagents,  4-aminoantipyrine  and
      the oxidant, potassium ferricyanide,
      are fairly stable. Refrigeration in the
      absence of light prolongs reagent  life
      by  a matter of weeks.  Variations in
      batches of 4 AAP have been observed
      but are not  troublesome.

   4   The reaction product fades slowly over
      a period of hours in the aqueous phase.
      The extracted material fades very
      slowly but the blanks tend to darken.
      The effect is not noticeable for a period
      of several hours.
   Because of the stability of the reagents
   and the uniformity of color response it
   is possible to prepare a semi-permanent
   standard curve.

   1   For phenol concentration under
      1.0 mg/liter all samples are extracted
      with chloroform to increase sensitivity.
      For phenol concentrations above
      1. 0 mg/liter readings may be made
      in the aqueous phase. A blank and one
      standard at 5. 0 mg/liter may be run
      as  a check on a previously prepared
      standard curve.

      Using the chloroform extraction
      procedure the response is linear
      from zero up to about 1.0 mg/liter.
      For aqueous phase readings the
      response is linear from about
      0. 1 mg/liter of phenol.
D  Substituted Phenolics

   The 4-aminoantipyrine reaction is
   applicable to phenolic compounds in which
   the para-position is not blocked by  an aryl,
   alkyl, nitro,  benzoyl,  nitroso or carbonyl
   group.  These do not give color when
   present in para-position.

   1  The color produced is of varying
      intensity.  Phenol, itself gives the
      greatest density.  Consequently, when
      using a standard curve referred to
      phenol itself, a mixture of substituted
      phenolics will give a minimum density
      value.

   2  Density of substituted phenolics
      compared to phenol:
      Compound


      Phenol
      O-Cresol

      M-Cresol

      P-Cresol
Density Compared to
	Phenol	

      100
       74

       69

        3
REFERENCES

Aminoantipyrine Procedure

1  Emerson, E. , Beachham,  H.H., and
      Beesle, L.C.  The Condensation of
      Aminoantipyrine. II  A New Color Test
      for  Phenol.  J.  Org. Chem.  8:417.
      1943.
                                                                                      23-3

-------
The Determination of Phenols
   Ettinger, M. B. , Ruchhoft, C.C.,  and          4  Mohler,  E.F., Jacor, L.N. Comparison  
      Lishka,  R. J. Sensitive 4-Amino-                 of Analytical Methods for Determination
      antipyrine Method for Phenolic                    of Phenolic Type Compounds in Water
      Compounds. Anal. Chem. j!3_:1783.               and Industrial Wastes Water.
      1951.                                            Presented at 130th Meeting of ACS.
                                                      Atlantic City.  September 16-21,  1956.
   Dannis,  M.  Determination of Phenols
      by the 4-Aminoantipyrine Method.
      Sew.  and Ind. Wastes.   23:1516. 1951.
 23-4

-------
          LABORATORY EXERCISE - ANALYSIS OF WASTE SAMPLE FOR PHENOL

                                       R. C.  Kroner*
I PRELIMINARY DISTILLATION

A  Reagents

   1  Phosphoric Acid, 10%

   2  Copper Sulfate,  10%

B  Procedure

   1  Place 250 ml of sample in a beaker and
      add 1 ml phosphoric acid solution.
      Using test paper, check to see that
      pH is <4.

   2  Add  1 ml of copper sulfate solution and
      transfer  to the distilling flask.  Con-
      nect flask to condenser and start dis-
      tillation.   Collect distillate in anErlen-
      meyer flask marked at 250 ml.

   3  When approximately 200 ml of the dis-
      tillate has been collected, withdraw the
      heat and  add 50 ml distilled water to
      the distilling flask.   Continue distilla-
      tion until 250 ml has been collected.
      Swirl the distillate in the flask to mix.


II DETERMINATION OF PHENOL BY 4-
  AMINOANTIPYRINE METHOD

A  Reagents

   1  4-Aminoantipyrine,  2% aqueous
U
   2  Potassium ferricyanide solution, 8%
      aqueous.

   3  Ammonium chloride buffer, pH  10 -
      dissolve 67. 5 g NH4C1 in 570 ml cone.
      NH4OH and dilute to 1 liter with dis-
      tilled water.

   4  Standard phenol solution,  1 ml =  1 mg

B  Procedure

   1  Prepare a 5 mg/1 phenol standard by
      diluting  exactly 5 ml of the standard
      phenol solution to 1 liter with distilled
      water.

    2  Measure duplicate 100 ml portions of
      the 5 mg/1 standard into labelled Erlen-
      meyer flasks.

    3  Prepare a blank by measuring  100 ml
      distilled water into a labelled Erlen-
      meyer flask.

    4  Measure 100 ml of the distillate into
      a labelled Erlenmeyer flask.

    5  To the standards, blank, and sample add:

      2 ml ammonium chloride buffer

      2 ml 4-AAP reagent

      2 ml potassium ferricyanide reagent

      Mix well after each addition

    6  Measure the optical density of each of
      the standards, blank, and sample at
      510 m^,  using a 1. 0 cm cell.

    7  Record the  readings on the  data sheet
      and compute the concentration of phenol
      in the original sample,  in mg/1.


Ill  DETERMINATION OF PHENOL BY 4-
    AMINOANTIPYRINE METHOD (EXTRACTED)

 A  Reagents

    1  4-Aminoantipyrine solution, 2% aqueous

    2  Potassium ferricyanide  solution,  8%
      aqueous

    3  Ammonium chloride buffer, pH 10 -
      dissolve  67. 5 g NH4C1 in 570 ml cone.
      NH4OH and dilute to 1 liter with dis-
      tilled water.

    4  Standard phenol solution, 1 ml  =   1 mg
 *In Charge, General Laboratory Services, Water Quality Section,  DWS&PC, SEC.  Reviewed
 December  1965.
 CH.PHEN. 31. 11. 61
                                                                                         23-5

-------
Laboratory Exercise - Analysis of Waste Sample for Phenol
   5  Chloroform,  Reagent grade.

B  Procedure

   1  Prepare a 0. 05 mg/1 (50 ppb) phenol
      standard by diluting  exactly  5.0  ml
      of the standard phenol solution to 1 liter
      with distilled water,  then diluting 10 ml
      of this solution to 1 liter.  The final
      standard contains 0.  05 mg/1.

   2  Transfer 500 ml of the above standard
      solution to a  1 liter separatory funnel.

   3  Prepare a blank by measuring 500 ml
      distilled water into a 1 liter separatory
      funnel.

   4  Dilute 10 ml of the distillate  to 1 liter
      with distilled water,   Transfer 500 ml
      of the diluted sample to a 1 liter separa-
      tory funnel.

   5  To the standard, blank,  and sample in
      the separatory funnels add:

      3 ml ammonium chloride buffer
3 ml 4-AAP reagent                   

3 ml potassium ferricyanide reagent

Mix well after each addition

Extract the solutions serially with 15,
10, and 5 ml volumes of chloroform.
Collect the chloroform  extract by
filtering through paper  into a 25 ml
graduate.  Make up to 25 ml with
chloroform.

Measure the  optical density of the  stand-
ard,  blank, and sample at 460 mji, using
a 5. 0 cm cell.

Record the readings on the data sheet
and compute  the concentration of phenol
in the original sample by multiplying the
measured concentration by 100.
 23-6

-------
LABORATORY EXERCISE - ANALYSIS OF WASTE SAMPLE FOR PHENOL
                             DATA SHEET
4-AMINOANTIPYRINE METHOD (AQUEOUS)
          Flask





          Blank




          Standard




          Standard




          Sample
O. D.
4-AMINOANTIPYRINE METHOD (EXTRACTED)
          Funnel






          Blank




          Standard




          Sample
O. D.
Cone, phenol, mg/1





       0




     5.0




     5.0
Cone. phenol, ppb





       0




      50
      Cone, phenol in original sample = ppb in diluted sample X 100.
                                                                           23-7

-------
                     SOURCES,  EFFECTS AND ANALYSIS OF CYANIDES

                                       F. J. Ludzack*
 I   SOURCES EFFECTS AND ANALYSIS OF
    CYANIDES

 A  Cyanides commonly are a first considera-
    tion in fish kills just as phenols are com-
    monly credited for objectionable water
    taste or odor.  The fact that many other
    pollutants or conditions can and do  cause
    similar  effects may not prevent unjust
    accusation.  Care must be used in dis-
    charge and records to protect the public
    and the processor.

 B  Fish toxicity has been reported at 0.025
    mg/1 CN.   Microorganisms generally are
    more tolerant.   Certain organisms  are
    adaptable to the destruction of cyanides.
    Activated sludge or trickling  filters suc-
    cessfully destroyed 60  mg/1 feed cyanide
    producing a nitrified effluent  with negli-
    gible cyanide.  Cyanide is an enzyme
    blocking agent, therefore,  toxicity  depends
    upon reactivity of essential enzymes and
    cyanide  and the relative fraction of  in-
    activated enzyme.  HCN is similar  in
    action to CO in human toxicity.
II   INDUSTRIAL SOURCES OF CYANIDES

 A  Metal plating

 B  Case hardening

 C  Metal cleaning baths

 D  Silver and gold refining

 E  Gas scrubbers from pyrolytic processes,
    (coking, refining, blastfurnaces.)

 F  Rubber, acrylic fiber,  plastic industry.
    Mainly  as  copolymers with nitriles.

 G  Chemical process intermediates
III   CYANIDE TREATMENT

  A  Lagooning - may lead to complexation,
     oxidation,  polymerization or volatilization.

  B  Acidification and aeration transfers HCN
     to the air.

  C  Lime-sulfur treatment forms less toxic
     SCN".

  D  Complexation with heavy metals - of
     doubtful value.

  E  Precipitation as heavy metal salts - re-
     quires close control.

  F  Oxidation with  KMnO4, ClOg, O3,  C12.
     Alkaline chlorination currently gives best
     results. Cr   oxidation conditions have
     not been found.           '

  G  Biochemical oxidation for low
     concentrations.
                 v
  H  Ion exchange

  I   Electrolytic oxidation for high
     cone ent rations.
IV  Reactivity and the variety in form of cya-
 nides cause major difficulties in treatment or
 analysis and require individual handling of
 each problem.

 A Major forms of cyanide include:

    1  Simple  soluble cyanides -
       H+Na+K+NH4+

    2  Simple  insoluble cyanides -
       Ni(CN)2 Zn,  Cd, etc.

    3  Complexed cyanides - association
       products of 1 &  2.
 *Chemist, Chemistry and Physics Section, Basic and Applied Sciences Branch,  DWS&PC, SEC.

 CH.Cy.18a. 12. 65                                                                       24-1

-------
Sources, Effects and AnalysiSLof Cyanides
   4  Organic cyanides - R-CN (Nitriles).

   5  Cyanates (OCN~) and thiocyanates
      (SCN~).

   6  Organic compounds degrading to form
      HCN during analysis (glycine).

B  Item Al is the only one that can be treated
   or analyzed efficiently. Other forms
   must be converted to simple soluble cya-
   nides during or prior to treatment or
   analyses.   Other forms of cyanide may be
   considered as interferences.
V  ANALYTICAL INTERFERENCE CONTROL

A  Insoluble and complexed cyanides gener-
   ally can be converted to simple cyanides
   by the Serfass distillation technique in the
   presence of HgC^, MgCl-2 and acid. Cer-
   tain copper and cobalt complexes  and prob-
   ably others are not converted completely
   to simple  cyanides except after extended
   distillation periods.

B  Sulfides - precipitate with PbCO3 before
   analysis.

C  Fatty acids or other organic turbidity -
   frequently may be extracted with iso-
   octane,  hexane or chloroform from slightly
   acid solution.

D  Amines -  extract from slightly alkaline
   solution as in V,  C.  The three solvents
   will not extract detectable HCN.

E  Oxidizing  agents may destroy HCN. Test
   with starch-Kl paper and titrate with
   sodium sulfite to a negative test before
   analysis.

F  Turbidity  - remove by acid distillation.
   Trace quantities may be controlled by
   extraction of the cyanide color complex.

G  Color-try extraction, distillation or both.

H  SCN" and  OCN" acid distillation destroys
   them.
     Organic cyanides or organics degrading to
     cyanide under analytical conditions gen-
     erally interfere to a degree depending
     upon the individual constituent.  No general
     method  of removal can be recommended.
     Results are open to question as these con-
     stituents may produce false cyanide tests.
     Nitriles and organic nitrogen compounds
     may produce low level interference.  Acid
     distillation may help.

     Buffer capacity of the sample may raise
     the pH above 8. 0 during color formation
     which decreases  resulting absorbance'
     materially.
 VI  ESTIMATION OF CYANIDE

  A Silver nitrate titration using p-dimethyl
     aminobenzalrhodanine indicator is recom-
     mended when cyanide is 1 mg/1 or higher.

  B Pyridine pyrazolone color test recom-
     mended when CN is less than 1 mg/1.
     May use aqueous or extracted absorbance
     reading.  Indicated CN of approximately
     0.005 mg/1 is questionable.
VII  GENERAL CONSIDERATIONS

  A Available methods of analysis cannot sep-
     arate so called "free" and "total" CN.
     Certain complexes are stable enough to
     prevent complete analytical recovery.
     Part of the complexed cyanide invariably
     is included with the simple cyanides.
     Easily hydrolyzed cyanides will be recov-
     ered in high yield;  stable complexes may
     not.

  B Sample preservation is never 100%  effec-
     tive.  Complexes may form or dissociate
     in storage.  HCN may volatilize.  Prompt
     analysis is recommended.  Alkali addition
     to pH 11 or above and cold storage is the
     next best approach.

  C Importance of distillation  cannot be over
     estimated.  It should not be omitted unless
     check tests with and without  distillation
     are comparable.
24-2

-------
                                                     Sources, Effects and Analysis of Cyanides
  D  Serfass  distillation with HgCl2 and MgCl2
     is recommended.  One hour of reflux will
     result in recovery of easily hydrolyzed
     cyanides in high yield along with part of
     the stable complexed cyanide.  If cyanide
     appears during a second one hour  reflux
     stable cyanides are indicated and low re-
     covery may be expected.

  E  Results  should be expressed in terms of
     the CN  ion even though it generally does
     not exist in the sample as such except in
     small proportions.
/Ill  COMMENTS, CN PROCEDURES,  11TH
     ED. OF STANDARD METHODS

  A  Comments on "free" cyanide may  be
     misleading.
                                    i    II
  B  Certain complexes containing Cu Cu
     mixtures may be highly resistant to acid
     distillation although most copper cyanides
     are recovered in good yield.

  C  UndissociatedHCN is generally considered
     more toxic to fish than the CN" ion.  Rel-
     atively little CN"  occurs in samples except
     at high pH values.

  D  Use of  the work "screening"  in place of
     "interference control"  is popular but
     somewhat confusing.

  E  The color test is not particularly sensitive
     to "salt" concentration unless the  salt
     buffers the color mixture to a pH greater
     than 8.0.  Color will not form consistently
     in strongly alkaline solutions.  See item N.

  F  Kruse and Mellon also  suggested extraction
     of cyanide from aqueous samples.   The
     best partition coefficient found was about
     0.4 for transfer of HCN to the organic
     solvent which does not  contribute to a high
     CN yield.  Removal of  interference as
     described is effective.

  G  Apparatus item 2. 1 may be obtained as
     Sargent No.  34087 including the  air inlet
     (item 2. 2).  The Fisher Milligan gas
     washer is difficult to seal, drain,  and
     rinse, and is not recommended.  Sargent
     No.  39623 is the one indicated for  item 2. 4.
 H Reagent 3. 2 is likely to be hard to pre-
    pare as it is very close to a saturated
    solution at room temperature.  The
    strength of  mercuric chloride is not
    critical - from 3 to 5 per cent solution is
    adequate and easier to  dissolve.

 I  It is not advisable to increase the air
    rate if the liquid starts to back up into
    the air  inlet.  Decrease the heat instead.
    A high air rate is likely to blow cyanide
    through the absorber.   An air rate below
    that of bubble coalescence in the spiral
    is suitable.   A heating  mantle with a
    powerstat control may  be set to avoid
    difficulties  during warmup.

 J  5 ml of acid is adequate for up to 1000 ml
    of sample providing excess alkali has been
    neutralized. The suggested 5 ml/100 ml
    solution may result in low yields.  Distil-
    lation pH of about 1.5 is  desirable.

 K Item 1.  2 titration method.  Distillation
    will not remove interference  such as H^S,
    fatty acids,  or volatile  color.

 L Item 3.5 Colorimetric  Method.  If the
    chemical does not dissolve immediately
    the analyst  can expect difficulties due to
    changes in storage. Replace with new
    chemical.

 M Item 3.  8 Use Eastman  6969,  3, 3'-dimethyl-
    1, 1'diphenyl (4, 4'-bi-2-pyrazalene)-5,
    5' dione.

 N Color Procedure item 4.1.  Dilute with
    distilled water.   If the  suggested NaOH
    solution is used here it will raise the pH
    above the point of maximum color
    development.
 REFERENCE

 Standard Methods, Water and Wastewater,
4/J' Hth Edition includes a good reference
    list.  Additional biological treatment
    information may be found  in the following:

 NITRILES

 1  Sew.  & Ind. Wastes 31,  No. 1, 33, 1959.
                                                                                         24-3

-------
Sources, Effects and Analysis of Cyanides
2  Proc 13 Ind. Waste Conf., Purdue Univ.,        4  J.W.P.C.F.  33, p. 492, May,  1961.
      Ext.  series 96,  p.  297, May, 1958.               Act Sludge tr. of Cn,  OCN, and SCN.

3  Proc. 14th Ind. Waste Conf., Purdue           5  Proc.  15th Ind.  W. Conf. Purdue Univ.
      Univ.,  Ext. series 104, p. 547, May,             Eng. Ext.  series 106, p. 439, May,
      1959.                                            1960.
24-4

-------
                         LABORATORY PROCEDURE FOR CYANIDE
                                       B. A. Punghorst*
      Serfass Distillation Procedure

 I   REAGENTS

 A  Sodium hydroxide, 4% aqueous solution.

 B  Mercuric chloride,  5% aqueous solution.

 C  Magnesium chloride solution - add 51 gms
    of MgCl2- 6H2O to flask,  dissolve in
    minimum quantity of water and make up
    to 100 ml volume.

 D  Sulfuric acid, concentrated.
 H  Drain the contents of the gas scrubber
    into a 250 ml volumetric flask and bring
    to the mark with washings from the gas
    scrubber and connections.  Hold for
    subsequent  analysis.
    Williams Cuprous Chloride Procedure

 NOTE:  It is recommended that this distillation
 technique be used for samples containing less
 than 1 mg/1 cyanide.  In samples of this type
 low recoveries have been obtained using the
 Serfass Distillation.  (See Reference  1.)
II   PROCEDURE

 A  Add 50 ml of 4% NaOH to the gas washer
    and dilute with distilled water until the
    spiral is  covered.

 B  Add 250 ml of sample to the boiling flask.
    Dilute to  500 ml if necessary.

 C  Connect the  train  (boiling flask, condenser,
    gas washer and trap) to the vacuum line
    and adjust the pressure so that approxi-
    mately one bubble of air per second enters
    the gas scrubber.

 D  Add 20 ml of mercuric chloride solution
    and 10 ml of magnesium chloride  solution
    through the air inlet tube.   Rinse  the tube
    with distilled water.

 E  Add slowly 5 ml of cone, sulfuric acid
    through the air inlet tube and rinse with
    distilled water.

 F  Heat the sample to boiling,  using  extreme
    care and  attention to prevent the sample
    from backing up into the air inlet  tube.

 G  Reflux the sample for one hour.  Remove
    the burner and continue the air flow for
    about ten  minutes.
 I   REAGENTS

 A  1:1 H2SO4

 B  Cuprous Chloride

 C  Sodium Hydroxide, 4% Aqueous Solution


II   PROCEDURE

 A  Add 50 ml of 4% NaOH to the gas washer
    and dilute with distilled water until the
    spiral is  covered.

 B  Add 250 ml of sample or an aliquot diluted
    to 250 ml Claissen flask.

 C  Connect the train (boiling flask, condenser,
    gas washer and trap) to the vacuum line and
    adjust the pressure so that approximately
    one bubble of air per second enters the gas
    scrubber.

 D  Slowly add 50 ml of 1:1 H2SO4 through the
    air inlet tube and rinse with distilled water.

 E  Add one-half gm Cu2Cl2 to the flask by
    washing with distilled water.
 *Chemist, DWS&PC Training Activities, SEC.

 CH. Cy. lab. Ic. 12.65
                                       24-5

-------
 Laboratory Procedure for Cyanide
 F Heat the sample to boiling, using extreme
   care and attention to prevent the sample
   from backing^up into the air inlet tube.

 G Reflux for 2 hours.

 H After removing heat continue air flow for
   about 10 minutes.

 I  Drain the contents of the gas scrubber
   into a 250 ml volumetric flask and bring
   to mark with washings from the  gas
   scrubber and connections.  Hold for
   subsequent analysis.
    Silver-Nitrate and Rhodanine Indicator
           (Modified Liebig Method)
 D Titrate a 200 ml aliquot of the distilled
    sample and record the titration volume.
    Save remaining distillate for colorimetric
    analysis.
                    DATA
              Blank     Standard   Sample
ml used      _
Corrected
titration value _
mg CN~/aliquot_
mgCN'Aiter
 I   REAGENTS

 A  Silver nitrate solution,  0.0192 N.
    Dissolve 3. 27 gms of silver nitrate in
    1. 0 liter of chloride-free distilled water;
    1 ml =  1 mg CN~.  Standardize against
    standard NaCl using the Mohr method.

 B  p-dimethylamino benzalrhodanine
    solution.  Dissolve 0. 02 gms of rhodanine
    compound in 100 ml of acetone.

 C  Stock cyanide solution,  1.0 mg/ml
    (1000 ppm).

 D  Sodium hydroxide, 4% aqueous solution.
II   PROCEDURE

 A  Familiarization with End-Point

    Run several blank determinations as
    follows:  Place 50 ml of 4% sodium
    hydroxide and 150 ml of distilled water
    in a 500 ml Erlenmeyer flask.

 B  Add about 10 drops of rhodanine indicator
    and titrate with silver nitrate to the first
    distinct color  change  (yellow to pink).

 C  Repeat the above  exercise  using 2. 0 or
    4. 0 ml of CN" stock solution.
Ill  CALCULATION
        -/ liter - (ml of AgNO3 - ml for blank) 1000
                     ml of sample titrated
  NOTE: If the above result is less than 1 mg/1,
  proceed with the colorimetric determination.
     2, 4. A. 1 0 APPARATUS - SCHEMATIC OUTI.INK
      K.H. Satgi-nt Calalof; Nos. nml Pru rs Givrn
 24-6

-------
                                                         Laboratory Procedure for Cyanide
      Pyridine-Pyrazalone  Method

I  REAGENTS

A  Chloramine T, 1% aqueous solution.
   (Prepare fresh daily.  If this does not
   dissolve rapidly it indicates Chloramine
   T degradation and probable analytical
   difficulty.)

B  1-phenyl,  3-methyl, 5-pyrazalone,
   saturated aqueous solution. Add 3-4 gms
   of the pyrazalone compound to  500 ml of
   water and bring to boil.  Cool,  let stand
   overnight and filter the appropriate volume
   prior to use.  The solution is stable
   indefinitely.

C  Bis-pyrazalone.  Dissolve 0. 025 gm  of
   bis-pyrazalone in 25 ml  in pyridine
   (prepare fresh daily).  Eastman 6969,
   designated as 3, 3'-dimethyl-1, 1'diphenyl-
   (4, 4'-bi-2-pyrazalone)-5, 5'dione.

D  Mixed Reagent

   Immediately prior to use, pour 125 ml of
   solution #2 and 25 ml of  solution #3
   together and mix.  (Prepare fresh daily.)

E  Acetic acid 1:4
    Cyanide stock standard,  1.00 gms
    CN~/liter.  Dissolve 2. 51 gms potassium
    cyanide in 1.0 liter of distilled  water.
    Add 2 or 3 pellets of sodium hydroxide to
    increase stability.   Standardize against
    silver nitrate and recheck weekly.
II   PROCEDURE

 A  Preparation of Standards

    1  Prepare a working standard by diluting
      accurately 1. 0 ml of the stock standard
      to 1. 0 liter.   (This solution is equiva-
      lent to 0. 0010 mg CN'/ml).

    2  Add 0,  1.0,  2.0, 3.0,  5. 0  and  7. 0 ml
      of the working standard to each test
      tube and dilute to the 25. 0 ml mark.

 B  Preparation of Sample

    1  Dilute remaining 50 ml of distillate to
      about 150 ml.  Transfer to a 400 ml
      beaker and neutralize with  1:4 acetic
      acid using a pH meter.  (Caution:  Do
      not over titrate with acid.)   Dilute to
      250 ml with distilled H2O.

    2  Add 10 ml and 20 ml portions of
      neutralized sample to separate test
      tubes.  Dilute to 25. 0 mark.
                                           DATA

Standard





Sample

Volume Used, ml
0
1
2
3
5
7
10
20
mg CN~ in 25 ml
0
.0010
.0020
.0030
.0050
.0070
--
--
Absorbance Reading
620 mn, 1.0 cm cell
--
--
--
--
--
--
--
--
                                                                                       24-7

-------
Laboratory Procedure for Cyanide
C  Color Reaction

   1  Add 0. 2 ml of Chloramine T solution
      to each standard and sample.  Mix and
      let stand for 3 minutes.

   2  Add 5 ml of mixed reagent to each test
      tube, mix and let stand for  20 minutes.

   3  Read the absorbance of each sample
      and standard in a 1.0 cm cell at 620 mix,
      using the O standard as a blank.

D  Calculation

   1  Construct a standard curve, plotting
      mgs CN~ vs optical density.

   2  Apply readings from samples to curve
      and calculate  mg CN~Aiter in the sample.
REFERENCES
   Finger, J.  H.   Recovery of Simple
      Cyanides by the Serfass Distillation
      Procedure as Compared with the
      Williams Cuprous Chloride Method.
      Lab. Investigations Report No.  2,
      Technical Advisory and Investigations
      Section, Technical Services Branch,
      Division of Water Supply and Pollution
      Control.  April 7,  1964.
2  Gonter, C. E. and Schmitt, J.  W.  Deter-
      mination of Cyanides in Water and
      Waste Samples.  Paper presented before
      the Division of Water and Waste Chem-
      istry, ACS, New York,  New York.
      September, 1963.

3  Standard Methods for the Examination of
      Water and Wastewater,  llth Edition.
      APHA, AWWA, WPCF.  1960.
24-8

-------
                 RECENT ADVANCES IN ESTIMATING FLUORIDES IN WATER
                                       R. C. Kroner*
  I  INTRODUCTION

  Today more than 2, 000 cities and towns in
  the United States, serving more than 40
  million people,  add fluorides to their public
  supplies as a caries preventive.  For this
  purpose,  the  concentration of fluoride is
  maintained at approximately 0. 8 to 1.2 mg/
  liter.  However, water supplies in many
  parts of the country contain naturally occur-
  ring fluorides in varying quantities,  and in-
  dustrial discharges often contribute additional
  fluorides to the normal content.
 II  ANALYTICAL REQUIREMENTS

  Since a wide range of skills and experience is
  exhibited by the personnel regulating the
  fluoridation procedures,  a simple, foolproof
  method for measuring microquantities in water
  is required.   The measuring procedure is
  frequently preceded by a separation procedure,
  usually a distillation, for removal of inter-
  ferences.  The analytical requirements then
  are resolved into:

    1  Rapid, dependable separation
       procedure

    2  Rapid, simple  measuring procedure,
III  SEPARATION PROCEDURE

 A  The older separation procedure still in
    use'*)  is the Willard-Winter steam dis-
    tillation.  This procedure has the follow-
    ing shortcomings.

    1  The apparatus used is fragile and
       unhandy.

    2  Temperature control is extremely
       critical because too low a temperature
       does not recover the fluoride and too
       high a temperature leads to sulfate
       carryover from the sulfuric acid dis-
       tilling media.
   3  Constant attention by the analyst is
      required.

B  A more recent distillation procedure by
   Bellack(2) employs distillation of a sample
   from a fixed ratio of sulfuric acid-water
   medium, using very simple glassware.
   The advantages of this procedure are:

   1  Simplicity of equipment

   2  Rapid distilling time

   3  The procedure does not require
      constant  attention

   4  The sulfate carryover is negligible.
                  (12)
C  A recent method     employs the ion-
   exchange as a means of separation, using
   an ahionic resin.   A resin slurry is
   pipetted into a column and allowed to
   settle and purified sand is added to cover
   and preserve the moisture of the resin.
   The sample  may be poured directly into
   the column  reservoir - with one exception.
   If aluminum is present above 0. 5 ppm,
   pretreatment of the sample is necessary.
   Pretreatment consists of dosing the sample
   with an ammonium-EDTA solution and ad-
   justing the pH to 11-12.  The fluoride ion
   is eluted from the  resin by addition of a
   beryllium-acetate  solution to the column
   reservoir.   The eluate is collected and
   the SPANeS^7) procedure for measuring
   fluoride concentration is  followed.  The
   advantages  of this  method are:

   1  Complete elimination of distillation
      equipment.

   2  The operation is self-sustaining so that
     the analyst need not be in close
      attendance.

   3 Ability to handle multiple samples
      simultaneously.

   4 Savings in time and equipment.
 *In Charge, General Laboratory Services,  Water Quality Section, Water Pollution Surveillance
 System,  1014 Broadway,  Cincinnati, Ohio.  Revised by John M. Matthews, Chemist,  Analytical
 Reference Service,  Training Program, SEC.  Reviewed December 1965.
 CH. HAL. f.33b. 11.64                                                                 25-1

-------
  Recent Advances in Estimating Fluorides in Water
IV  MEASURING TECHNIQUES

 A The two Standard Methods in current use
    are based upon the complexation of zir-
    conium with alizarin dye to form an intense
    red solution.  When a small amount of
    fluoride ion is added, a zirconium-fluoride
    complex is formed,  thus lessening the
    intensity of the red color of the solution.
    As  the concentration of fluoride increases,
    the solution becomes less  red and begins
    to turn  yellow.  A point is finally reached
    at which the addition of further fluoride
    does not appreciably change the color of
    the solution.

    The older Scott-Sanchis and Lamar
    methods were designed for use with Nessler
    tubes,  i.e., are visual methods.  The
    Megregian-Maier method used different
    concentrations of zirconium and alizarin
    and different acidity which adapts the pro-
    cedure to photometric measurement of
    the color intensity.  The disadvantages of
    these methods are roughly the same for
    each:

    1  Sensitivity to interferences,  especially
       sulfate, phosphates and aluminum

    2  Time required for completion of color
       reaction, especially with regard to
       the  Megregian-Maier procedure
 B A procedure developed by Megregian
    uses a different dye,  Eriochrome Cyanine
    R,  which gives rapid color production.
    Procedures are also  given to overcome
    the interferences due to sulfate and
    aluminum.  The net result is a photometric
    method which gives:

    1  Complete color formation in about  15
       minutes

    2  Built-in steps for  removal of two
       important interferences
    However, since the method is very sensi-
    tive to sulfate, this correction step must
    be included in most measurements.   In
    order to circumvent the effect of sulfates.
           (6)
   Thatcher    incorporated barium chloride
   into the ECR reagent to precipitate the
   unwanted sulfate.  This step accomplishes
   the desired result,  but the time advantage
   is lost because of the period required for
   growth and settling of the  barium sulfate
   crystals.
                                      (7)
C  A newer method proposed by Bellack
   employs a dye known as SPADNS* which
   replaces the alizarin dye of the older
   methods.  The dye  solution is incorporated
   into the zirconium salt solution so that only
   one reagent is required.  The advantages
   claimed for this procedure are:
       180*C
                                                            Bellack Fluoride Still
*Eastman Catalogue #7309 (4, 5 Dihydroxy-3-
 (p - s ulf ophe nyazo)-2,7- naphthalene - disulf onic
 acid,  trisodium salt.
 25-2

-------
                                            Recent Advances in Estimating Fluorides in Water
   1  One shot reagent

   2  Color completion in less than 5
      minutes

   3  Built-in correction for aluminum
      interference

   4  No pH adjustments required for
      sample.
D  Other methods which have been proposed
   include:

   1  A method for turbidimetric titration of
      fluoride with thorium nitrate'8)

   2  Displacement of silicon from a silicon
      fluoride compound and subsequent re-
      action of the free silicon to form a
      heteropoly blue compound.  The amount
      of color formed is proportional to the
      amount of fluoride in the silicon-
      fluoride compound^) and'   '.
   3  Titration of a fluoride sample with
      thorium nitrate and subsequent
      measurement of the resulting color by a
      recording spectrophotometer.'  '
V  STANDARD METHODS, llth EDITION

A  The Standard Methods  which was issued
   in 1960 made the following changes:

   1  The Willard and Winter steam dis-
     tillation  was retained as the Standard
     Method.

   2  The Bellack distillation procedure was
     included on a tentative basis.

   3  The Lamar visual method was excluded.

   4  The Scott-Sanchis visual and the
     Megregian-Maier photometric methods
     were retained as referee  methods.

   5  The new SPADNS photometric method
     was included on a tentative basis.
                               TABLE OF INTERFERENCES
Concentration of Substance, In mg/1, Required to Cause
An Error of (+) or (-) 0. 1 mg/1 at 1. 0 mg/1 F

Alkalinity
Al+++
Cl"
Fe+++
(NaP03)g
"PO A "
i\-JA
SO4"
Scott-Sanchis
400(-)
0. 25(-)
2, OOO(-)
2(+)
LOW
300(+)
Megregian-Maier
325(-)
0. 2(-)
1, 800(-)
5(-)
1. K+)
400(+)
SPADNS
5, OOO(-)
0. !(-)*
7, 000(+)
10(-)
1. 0(+)
200(+)
Chlorine Must Be Completely Removed With Arsenite
Color & Turbidity Must Be Removed or Compensated For
          *Above Figure is For Immediate Reading.  Allowed to Stand Two Hours
           Tolerance is 3.0 mg/1.  Four Hour Tolerance is 30 mg/1.
                                                                                     25-3

-------
Recent Advances in Estimating Fluorides in Water
REFERENCES

1  Standard Methods for the Examination of
      Water, Sewage and Industrial Wastes.

2  Bellack,  E.  Simplified Fluoride Distil-
      lation Method.  Jour.  AWWA, 50,
      April  1958.  p 530.

3  Campbell, S. T., Chief Chemist, Torres-
      dale Plant.   Philadelphia.  Unpublished
      Data.

4  Shoup, R.  Removal of Interferences in
      The Scott-Sanchis Fluoride Determi-
      nation.  Anal. Chem.  29.  August 1957.
      p 1216.

5  Megregian, S.  Rapid Spectrophotometric
      Determination of Fluoride with Zir-
      conium-Eriochrom Cyanine R Lake.
      Anal.  Chem. 26.  1954.  pllGl.

6  Thatcher, L. L. Modified Zirconium
      Eriochrome Cyanine R  Determination
      of Fluoride.  Anal. Chem.  29. November
      1957.  p 1790.

7  Bellack,  E.,  and Schouboe, P.  Rapid
      Photometric Determination of Fluoride
      with SPANDS.  Zirconium Lake.
      Unpublished.

8  Brandt,  W. W., and Duswalt, A. A. Determi-
      nation of Fluoride Ion by Turbidimetric
      Titration.  Anal.  Chem. 30.  June 1958.
      p 1120.
 9  Curry, R.P.,  and Mellon, M. G.  Spec-  '
      trophotometric Determination of In-
      organic Fluoride and of Fluorine in
      Organic Compounds.  Anal. Chem. 29,
      November  1957. p 1633.

10  Curry, R. P.,  and MeUon, M. G.  Colori-
      metric Determination of Fluoride in
      Water by  Heteropoly Blue System.
      Anal.  Chem. 28. October 1956. p 1567.

11  Mennis, O.,  Manning, D. L.,  and Ball,
      R. G.  Automatic Spectrophotometric
      Determination of Fluoride.  Anal.
      Chem. 30.  1958. p 1772.

12  Kelso,  F. S.,  Matthews, J. M.,  and
      Krame r,  H. P.  Ion-Exchange Method
      for Determination of Fluoride in Pot-
      able Waters. Anal.  Chem.  36:577.
      March 1964.
 ADDITIONAL REFERENCES

 1  Kramer,  H. P., Kroner, R.,  and Ballinger,
      D. G.  Problems in Estimating Fluorides
      in Water. Jour. AWWA 48. May 1956.
      p 573.

 2  Thorn,  J. V.,  and Gribkoff, G. P.  Com-
      parative Fluoride Analysis by Several
      Methods.   Jour. AWWA 48. April 1958.
      p 455.
25-4

-------
                        LABORATORY PROCEDURE FOR FLUORIDE
                                   John M.  Matthews*
   REAGENTS
A Resin:  Purification

   To purify the resin,** wash in the following
   manner and decant after each wash.  Place
   450 grams of resin in a 1500-ml beaker,
   wash with two 300-ml portions of 95%
   ethanol; two 300-ml portions of distilled
   water; five 300-ml portions of 3 M hydro-
   chloric acid; then transfer to Sedwick
   Rafter cone and wash with 8 liters of dis-
   tilled water by  means of the siphon arrange-
   ment.  Transfer resin to 1500-ml beaker,
   add 300 ml of 1 M sodium acetate solution
   and stir with magnetic stirrer for 15
   minutes.  Discard supernatant.  Prepare
   a 1:1 slurry of  the acetate-resin and dis-
   tilled water and store in a closed poly-
   ethylene container.

B Beryllium Eluting Solution - Stock
   Solution

   Pipet 57 ml of glacial acetic acid into 500
   ml of distilled water,  dissolve 2.6 grams
   of reagent grade beryllium carbonate
   (BeO)5-CO2'5H2O*** and dilute to 1 liter
   with distilled water. (Note toxicity of
   beryllium, and  exercise care.)

C Beryllium Eluting solution - Working
   Solution

   The beryllium stock solution is diluted
   1:10 with distilled water to provide the
   beryllium eluting solution used to remove
   the fluoride from the acetate resin.

D Sand: Purification

   Use purified white Quartz sand,**** 60-
   120 mesh.  Purify the sand by digestion
   at  100C for 1 hour with 250 ml of 20%
   sodium hydroxide, discard supernatant,
   and wash with 250 ml of  1:3 hydrochloric
   acid  solution.   Wash in 2-liter flask with
   distilled water  until all traces of chloride
   are removed.
 E Ammonium - EDTA Solution

    To prepare the 0, 13 M NH4EDTA solution,
    dissolve 50 grams of Na2C10H14O8N2'2H2O
    in 70 ml of concentrated NH4OH and dilute
    to one liter with distilled water.

 F SPADNS Reagent

    Dissolve 0.958 grams 4, 5-dihydroxy-3-
    (p-sulfonphenylazo) -2, 7-naphthalene
    disulfonic acid trisodium salt (Eastman    ,
    No.  7309)  in distilled water and dilute to /
    500 ml.

 G Acid-Zirconium Reagent

    Dissolve 0. 133 grams zirconyl chloride
    (ZrOCl2  8H2O) in 25 ml distilled water.
    To the  zirconium solution add 350 ml
    cone. HC1 and dilute to 500 ml.

    Combine equal volumes of the above re-
    agents to produce a single working reagent.

 H Reference Solution

    Mix  10 ml of SPADNS reagent solution
    with 103 ml of distilled water and 7. 0 ml
    of cone.  HC1.

 I  Fluoride Stock Solution

    Dissolve 0.2210 grams NaF in  1 liter of
    distilled water (1 ml = 0. 1 mg F).

 J  Standard Fluoride Solution

    Dilute 100 ml of the above stock solution
    to 1 liter (1 ml = 0.01 mg F).  From this
    prepare working solutions.
  **Dowex 2-x8,  Anionic Resin,  Cl  Form,
    50-100 Mesh.  Dow Chemical Co.
 ***Fisher Scientific Company
#***Fisk Sand Company, 40-38th Ave. North,
    Minneapolis,  Minnesota
*Chemist, Analytical Reference Service,  Training Program,  SEC.  Reviewed December 1965.
CH. HAL. f. lab. 1. 11.64                                                               25-5

-------
                                 \
 Laboratory Procedure for flucO&de -
^i
 II  PROCEDURE

( A Ion Exchange
                                     /.
     1  Preparation of columns for each
       standard and sample.

       a  While the magnetic mixer is stirring
          and purified resin slurry, pipet 25ml
          into each reservoir. After the resin has
          settled in the columns, rinse the remain-
          ing resin from sides of the reservoir.

       b  Add purified sand to each column to
          form a top layer approximately  1 cm
          high.  Wash the reservoirs with
          distilled water to remove all sand
          from the sides of the reservoirs.
          Allow the  water to drain completely -
          discard the drainage.

     2  Analysis of water sample

       a  If no aluminum is present in  the
          sample  then proceed to step b.  If
          alumium is present in  excess of
          0. 5 mg/1 then proceed as outlined
          below.

          1)  Pipet 50 ml of the standard
             fluoride working solution, (. 00
             mg,  .02mg,  .04mg, .06mg/50
             ml) into individual 125-ml Erlen-
             meyer  flasks.

          2)  Pipet 50 ml, or  an aliquot diluted
             to 50 ml, of sample into a 125-ml
             Erlenmeyer flask.

          3)  To each 50 ml volume of standard
             and sample pipet 1 ml of NH4EDTA
             solution followed by 2 ml of 0. 5
             N4NaOH.  Mix well.
                      4) Pour each standard and sample
                        into its respective prepared
                        column and allow to drain.  Dis-
                        card the drainage.  Proceed to
                        step d.

                   b  Pipet 50 ml of the standard fluoride
                      working solution into its prepared
                      column.

                   c  Pipet 50 ml, or an aliquot diluted
                      to 50 ml, of sample into the pre-
                      pared columns and allow to drain.
                      Discard the drainage.

                   d  Wash the columns by adding 100 ml
                      of distilled water to the reservoirs
                      and  allow to drain.  Discard the
                      drainage.

                   e  Remove the adsorbed fluoride  from
                      the resin by pipetting  100. 0 ml of
                      beryllium eluting solution into the
                      reservoirs.  Collect the eluate in
                      a 250-ml Erlenmeyer flask.

             B  Colorimetric (SPADNS)

                1  Pipet 20 ml of mixed SPADNS  solution
                   into each flask containing standards
                   and samples.  Mix well.

                2  Adjust  the temperature of the standards
                   and samples to within + 2C of each
                   other.

                3  Read the standards  and samples in 1 cm
                   cells against the reference solution at
             / iO -5*fr mji.  If aluminum was present in
             (0    the original sample and step 2a was
                   used for complete complexation of the
                   aluminum fluoride complexes, then a
                   30-minute waiting period is required
                   for a complete color development.

                4  Prepare a standard curve,  plotting
                   mg F vs. OD.
 25-6

-------
                       TRACE ORGANIC CONTAMINANTS IN WATER
                                        R.  L. Booth*
I  INTRODUCTION

The subject of trace organic contaminants
in water continues to receive ever-increasing
amounts of attention.  Concurrently, the
sources  of these refractory materials are
becoming more  varied and complex.  The
problems associated with these substances
are, likewise, increasing and satisfactory
water treatment is becoming more and more
difficult.
II   SOURCES

 A  Man-made

  i^l  Domestic wastes, in various stages of
      sewage treatment, discharged into
      rivers and streams.

  ^ 2  Industrial wastes, due to their multi-
      plicity and complexity.

    3  Carrier solvents, such as those  used
      in pesticide formulations.

    4  Chemicals applied directly to land
      and water.

 B  Natural

  /'l  Extracellular products of algae by
      (a) diffusion of metabolic intermediates,
      (b) by-products of metabolism,  and
      (c) hydrolysis of capsular materials.

  i/ 2  Actinomycetes, microorganisms present
      in rivers/streams, by their growth and
      decomposition cycles.   ( j<2.
-------
  Trace Organic Contaminants in Water
       where large quantities of organic
       materials are needed.
  B Isolation

    1  The carbon samples are sequentially
       extracted with chloroform and ethyl
       alcohol to desorb the organic material
       from the carbon.

       a  After extraction, the excess  solvent
          is removed,  and the samples are
          brought to dryness to yield a:

          1)  Carbon chloroform extract (CCE).

          2)  Carbon alcohol extract (CAE).  O*

    2  The CCE is separated into broad
       classical groups by techniques based
       on solubility differences.

    3  Further separations are made by such
       techniques as  adsorption, paper, and
       thin layer chromatography.

  C Identification

    1  Tentative identification is normally
       made by gas chromatography analysis.

    2  Positive identification normally
       requires infrared confirmation.
VI  TREATMENT AND REMOVAL PRACTICES

 A Plant treatment procedures, such as
    coagulation,  sedimentation,  and filtration
    are generally not too effective.

 B Chemical treatment

    1  Copper sulfate used to control algae.

    2  Oxidizing agents,  such as chlorine,
       chlorine dioxide, ozone,  and potassium
       permanganate are used with varying
       degrees of success.

    3  Activated carbon treatment removes
       organic substances by adsorption.
   C  Biological Treatment

      1   Natural degradation in unsaturated
         soils and streams.

      2   Biological oxidation of organic
         materials both in streams and
         acclimated systems.

 VII  SUMMARY

   The problems associated with trace organic
   contaminants in water are becoming more
V * apparent as our need  and usage of water
   increase.  The continued growth of the
   chemical industry,  our increasing population,
   and the public's demand for more palatable
   water emphasize even more the urgency of
   these problems.  Developments have been
   made in the detection of these refractory
   materials and in their removal from water
   supply sources.  It is apparent, however,  that
   further advances in the collection,  identification,
   and removal of these  pollutants are needed to
   insure the public of high-quality water and
   water resources.
   REFERENCES

   1  Anon.  Tentative Method for Carbon
         Chloroform Extract (CCE) in Water.
         Jour.  AWWA.  54, 223.  1962.

   2  Ryckman, D. W., Burbank,  N. C.,Jr.,  and
         Edgerley, E., Jr. New  Techniques for
         the Evaluation of Organic Pollutants.
         Ibid. 56, 975.  1964.

   3  Ettinger, M. B.  Developments in Detection
         of Trace Organic  Contaminants.  Ibid. 57,
         453.   1965.

   4  Robeck,  G. G., Dostal,  K. A., Cohen, J. M. ,
         and  Kreissl,  J. F.  Effectiveness of
         Water Treatment  Processes in Pesticide
         Removal.   Ibid. 57.  181.  1965.

   5  Anon.  Taste and Odor Control - Chemicals
         and  Methods.  Taste and Odor Cont.
         Jour.  31. No. 1,   1. 1965.
 26-2

-------
        METHODS  OF RECOVERING ORGANIC MATERIALS FROM SURFACE WATERS
                          R. H.  Burttschell and J.  J.  Lichtenberg*
Methods for recovering organic materials
from water may be classified according to
the degree of concentration required before
the desired analytical procedure can be
applied.

I  CONCENTRATED SOLUTIONS

Where only a minor degree of concentration
is involved, the following methods should be
considered.

A Liquid-liquid extraction usually involves
   water and an immiscible organic solvent.
   Solvents should be investigated in the
   series of increasing polarity:

         aliphatic hydrocarbons
         aromatic hydrocarbons
         ethers
         chlorinated compounds
         esters
         alcohols, amines, acids,  etc.

   pH may be of critical importance; this
   point will be discussed  at length in the
   discussion of Analytical Procedures.  In-
   organic salt concentration may also be
   important.

   Remember the concept  of the partition
   coefficient:
              K  =
Cs
Cw
   where  K  is the partition coefficient

        Cs  is concentration in the extract-
             ing solvent

        Cw  is the concentration in water

   Continuous extractors must be used where
   the K value is  not favorable to the extract-
   ing solvent. Continuous batch and counter-
   current extractors may be used.

   Separatory funnels are available in a variety
   of sizes.  Batch continuous extractors are
   commercially  available in sizes up to a
   liter or so and  can be readily assembed  in
    larger sizes.  Continuous counter-current
    extractors are convenient for up to 10-20
    gallons.

 B  Steam distillation can be used to strip a
    sample of small amounts of volatile or-
    ganic  compounds; in this case the distillate
    usually must be further concentrated  by
    liquid-liquid extraction.  The organic com-
    pound should have at least moderate vapor
    pressure at  100  C and should be almost
    insoluble in  water.

    A variation of this method is simple
    evaporation to concentrate non-volatile
    organic compounds.

 C  Precipitants may be used:  silver salts of
    acids, chloroplatinates or tetraphenyl
    boron, derivatives of  amines, phenylhy-
    drazine derivatives of ketones and alde-
    hydes, etc.

 D  Ion exchange may be used to concentrate
    acids  and bases.  The  only limit to the
    volume of water to be filtered is the
    amount of inorganic salts in the water;
    these  inorganic salts usually use up the
    exchange capacity too rapidly to make this
    method practicable.

II   VERY DILUTE SOLUTIONS

 To concentrate  extremely dilute solutions the
 carbon filter is the most useful method.   The
 organic matter  is adsorbed from aqueous so-
 lution and desorbed by an organic  solvent.
 The great advantage is the large amount of
 water that can be put through a small filter;
 the disadvantages lie in the lack of quantita-
 tive adsorption  and desorption.

 A  The Adsorption Process

    1  The adsorption process involves an
      equilibrium in solution.
                                      Adsorbed
                           .Unadsorbed
*Chemist,  Chemistry & Physics Section Section,  Basic and Applied Sciences Branch, DWS&PC,
SEC and Chemist, Water  Quality Section,  DWS&PC,  SEC.  Reviewed December 1965.
CH. OTS. 37a. 3.62
                                                                  27-1

-------
Methods of Recovering Organic Materials from Suv .ice Waters
   2  The Freundlich Isotherm is often useful
      in evaluating adsorption behavior.
                       1
               x
              m
= kc
      Units may be chosen for convenience.
      The larger _ the stronger the adsorp-
      tion. The  n   constant k gives the
       value at unit concentration.
      m
        x =  weight of adsorbed  compound
        m =  weight of carbon
        k =  constant
        c =  equilibrium concentration of
              organic compound in the liquid
              phase
          =  constant
   3  General rule: non-polar compounds are
      strongly adsorbed and polar compounds
      weakly adsorbed from water e. g.  , mi-
      meral oil  is more strongly adsorbed than
      glycine.

   4  Adsorption will depend on the type of
      carbon, grain size, pH of solution, po-
      larity of adsorbate, nature of the  sol-
      vent,  temperature, etc.  If powdered
      carbon is  not used, the column length
      and contact time must be chosen so as
      to permit  efficient adsorption.

   5  Desorption is simply the reverse  re-
      action in the adsorption equilibrium
      and is influenced by the same factors
      as adsorption.  It is usually necessary
      to use an  organic solvent for desorption
      with an extended period of extraction.

B Setting up the Carbon Filter

   1  In the next section is a description of
      the procedure used in setting up and
      running carbon filters in our laboratory.
      It should,  however, be understood
      that elaborate apparatus is not required
      and that excellent results can be ob-
      tained with a piece of glass tubing
      closed at  either end by a rubber stopper
      in which is inserted a piece of smaller
      glass tubing.  Such apparatus is ade-
      quate for  testing  small volumes, e. g. ,
      sewage or concentrated industrial wastes
although not convenient for handling
thousands of gallons of water.

Wherever the  investigation is concerned
only with certain specific compounds,
bench tests in small columns should be
carried out in order to evaluate the per-
formance to be expected from the filter.
                               TTI INSTALLATION OF EQUIPMENT AND
                                   COLLECTION OF CARBON FILTER
                                   SAMPLES

                                A The carbon filter consists of a piece of
                                   pyrex glass pipe 3 inches in diameter and
                                   18 inches in length.  The ends are fitted
                                   with brass plates and 3/4 inch galvanized
                                   nipples.   A stainless steel screen is
                                   fixed in a neoprene gasket at both ends.

                                B Presetting,  Prefilter,  and Backwash

                                   River waters will frequently clog the car-
                                   bon filter before the desired amount of
                                   water has been sampled.  It is necessary
                                   to remove sufficient turbidity to permit
                                   the required amount of water to pass
                                   through the unit.   This  may require a pre-
                                   settling tank, and  a prefilter containing
                                   sand and gravel.   For waters having less
                                   than 100 ppm of turbidity, a presettling
                                   tank is generally not required.  Tap water,
                                   of course, requires no prefiltering and
                                   may be passed directly into the carbon
                                   filter.

                                C Presettling Tank

                                   A standard hot water tank connected with
                                   the inlet at the bottom and outlet at the top,
                                   with a clean-out tap at the bottom can serve
                                   as a presettling tank.  The outlet connects
                                   to the prefilter containing sand and gravel.
                                   The hot water tank should be flushed at fre-
                                   quent intervals to  prevent a large accumu-
                                   lation of solids.  Open settling tanks can
                                   be used if care is  taken to prevent long
                                   detention times and biological action. With
                                   open tanks a pump will be required to move
                                   the water through  the filter.

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                              Methods of Recovering Organic Materials from Surface Waters
D  Sand Prefilter

   The sand prefilter consists of a standard
   piece of steel pipe 3 inches in diameter
   and 3 feet long, threaded at both ends, and
   equipped with 3" X 1" reducer couplings.
   Two disks of stainless steel screen are
   fitted to the inside diameter of the pipe.
   A simple way to prepare and hold the screen
   in place is to cut out a disk about the size
   of the outside diameter of the reducer,
   and then push it into place  so that it is be-
   low the threads.  The screen is held
   tightly against the inside of the reducer.
   The pipe is packed with 6 inches of 1/8"
   gravel,  24" of 0.  6 to 0. 8 mm sand,  and
   another  6 inches of 1/8" -  1/4" gravel.
   No free  space is left in the pipe. The
   gravel should be packed by jarring the
   pipe while fitting.  This arrangement
    provides a strainer rather than a filter
    with a movable bed.   By such an arrange-
    ment backflushing can be done without
    disturbing the filter.   The construction
    details are shown in Figure 1.  The di-
    mensions may be varied according to
    local conditions.
 IV FILTER ARRANGEMENT

 A The presettling tank, the sand prefilter,
    and the carbon filter should be installed
    at the most convenient source of raw water.
    If less than 15 psi pressure is available,
    it may be necessary to pump the water
    through the system. A schematic drawing of
    a workable system is shown on the following
    page.  Exact lengths of pipes, etc. are
    not given,  since these will vary with the
                      16-18 Mesh
                      Stainless Steel
                      Screen	
                                           J~U-
                   Standard 3" Pipe
                   Threaded Each End
                     16-18 Mesh
                     Stainless Steel
                     Screen 	
 " X 1" Reducer Coupling
                                                 lo    l/8"-l/4" Gravel
     0.6 to 0. 8 mm Sand
                                                       1/8" - 1/4" Gravel
3" X 1" Reducer Coupling
                           FIGURE 1 - Details of Sand Prefilter
                                                                                       27-3

-------
 Methods of Recovering Organic Materials from Surface Waters
   local situation.   Both the sand and car-
   bon filters should be connected with unions
   at both ends for easy removal.  A typical
   installation is shown in the photograph on
   page 3-6.

B  The raw water passes into the bottom of
   the  sand prefilter, around and into the
   bottom of the carbon filter. When the rate
   of flow through the system falls below
   1/4 gpm backwashing of the sand filter is
   necessary, using a high pressure source
   of water.  A clean hose is connected to
   the  top of the sand filter, the valve to the
   carbon filter is closed,  the drain valve
   on the sand filter is opened and the sand
   is back-flushed until the water coming out
               is clear.   The length of time between      '
               backwashings will vary. On the Missouri
               River,  for example,  it has been found
               that once every 24 hours is sufficient.
               After backwashing connect the system as
               before  and continue the  sampling.  Be sure
               to disconnect hose at top of sand filter
               after backwashing.  A pressure gauge is
               inserted in the system to indicate when
               clogging is taking place in the carbon fil-
               ter.  Total pressure in  the filter should
               not exceed 50 psi.

            C  A water meter, located at the end of the
               system to prevent excessive fouling of
               the meter, is used to measure the vol-
               ume  of water samples.  It is good practice
                                  r
                        Union-
Hose Connection

	j   Valve
                                                                 Valve
                  Sand Prefilter'
                       Pump
                    (If Required)
                       Raw
                      Water
                                                                 Water
                                                                    Meter
                                                            Carbon Filter
                                             Pressure   ^ j2^Uni
                                              Gauge
      LJl
    Valve.
    Drain-
                                                                Flow
Regulator
(1/2 GPM)
                 Figure 2 - Schematic Diagram of Piping Installation for Sand
                              Prefilter and Carbon Filter
 27-4

-------
                              Methods of Recovering Organic Materials from Surface Waters
  to disassemble and clean the meter thor-
   oughly after each run.  A 5/8" X 3/4",
   disk-type meter, is fairly satisfactory.
   A valve following the meter serves  to
   throttle the flow  if necessary. A flow-
   regulating device may also be used  for
   this purpose.  The complete installation
   is shown in the schematic diagram,
   Figure 2.

 D Fine carbon washes out of the filter when
   it is first started.  A few gallons of water
   can be passed through the top connection
   and through the carbon filter drain before
   cutting in the meter, to keep the meter
   free of the carbon.   The hose connection
   and drain on the  carbon filter can be used
   to back-flush the carbon should it become
   clogged.  This is a last resort and  should
   only be used if absolutely necessary.

 E The system outlined is not intended to re-
   move all traces of turbidity from the water
   before passing through the carbon filter.
   Its  purpose is to take out gross materials,
   most organisms, and permit the required
   volume of water  to pass through the car-
   bon.  The valve nearest the bottom  of the
   sand filter is to be  closed when it is desired
   to obtain a sample of raw water directly
   for other analyses.  The drain valve is
   opened and, after flushing, the necessary
   raw water sample is collected.

 F Pumping

   1  If adequate pressure is not available
      for sampling raw water, it is neces-
      sary to pump  through the filter system.
      It is important that the pump used
      should not contaminate the sample
      through oily packing or other  sources.
      New pumps are  sometimes grease
      coated and should be thoroughly  cleaned
      before being put into service. If  a lift
      of more than 12  feet is required, it
      will be necessary to use a jet-type
      pump.  A model suitable for the  con-
      ditions should be selected.

   2  Before a new  pump is put into service,
      it should be thoroughly flushed with
      hot water containing a little detergent.
      The pump should be operated against
      the minimum, amount of head required
      to get the water through the filter. This
      may require by-passing of part of the
      flow.

G  Collection of Sample

   1  With fairly concentrated samples (sew-
      age,  industrial wastes,  etc.) a small
      filter and a few gallons  of water may
      be sufficient. Generally, for river
      sampling,  water should be passed
      through a large filter at a rate of 1/4
      to 1 / 2 gallons per minute  until up to
      5000 gallons or more have been filtered.
      With highly turbid waters  clogging may
      occur earlier. Although a suitable sam-
      ple can sometimes be obtained with
      several hundred gallons of river water,
      it is desirable to filter a minimum of
      2000 gallons if at all possible.  A flow
      regulating device set at 1/4 or  1/2
      gpm can be placed  in the system ahead
      of the carbon filter. A  suitable unit can
      be obtained from the Dole Valve Company,
      6201 Oakton Street, Morton Grove,
      Illinois.  These devices generally need
      a minimum pressure of 15 psi for proper
      operation.

   2  Since the purpose is to get a quantitative
      measure of organics in  water, it is very
      important to have accurate flow measure-
      ments. If difficulties in flow occur this
      should be noted on  a log sheet.  Meter
      readings should be recorded daily on
      log sheets and should be designated
      either in GALLONS or  CUBIC FEET.
      If a  satisfactory meter cannot be ob-
      tained, the flow rate for a set volume
      (1 or 2 liters) can be determined at
      regular intervals.

H  Precautions

   The purpose of the carbon filter is to ad-
   sorb small amounts of impurities from
   the water.  It is important to avoid contami-
   nation of the carbon from other sources.
   Hence the following should be observed:

   1  New galvanized fittings  are usually
      coated with oil or grease.  The oil
      should be removed by washing in kero-
                                                                                        27-5

-------
Methods of Recovering Organic Materials from Surface Waters
V
      sene followed by a detergent wash before
      such fittings are used for making con-
      nection to the filter.

    2  Ordinary organic pipe jointing com-
      pounds should not be used.  Red lead
      (lead oxide) mixed to a paste with water
      can be used for this purpose.

    3  Plastic hose is to be avoided,  and if
      rubber hose is used in any connections
      it should be flushed  thoroughly before
      being connected to the filter.  Copper
      tubing is ideal for connections.

    After the  required volume of water has
    been run  through the filter, the carbon is
    removed,  dried, and extracted.

    The wet carbon is spread out in a thin layer
    on a metal sheet and air dried for several
    days.  The time necessary for drying in-
    creases with the thickness  of the layer.
    Warm air can be passed over the surface
    of the carbon to hasten the  drying but with
    the  risk of driving off weakly held volatile
    substances.
LABORATORY TREATMENT OF SAMPLES
OBTAINED BY THE CARBON ADSORPTION
TECHNIQUE: EXTRACTION PROCEDURES
 The sample is collected by passing approxi-
 mately 5000 gallons of water through a carbon
 adsorption unit.   The unit is shipped to S. E. C.
 along with a daily record of the sampling activi-
 ty and the carbon treated as described below.

 A  Preliminary Treatment

    1   Records

       a  Log sample in - list date received -
         assign it a number.

       b  Send daily record sheet to the Lab-
         oratory where pertinent data are re-
         corded on a data card,  i. e. , source,
         location, dates sampled,  date re-
         ceived and total flow.

    2  Drying
       a  Remove wet carbon from the tube and
          dry it on copper,  brass or stainless
          steel trays  in an oven at  40C.  (N. B.
        air circulated through drying cabi-
        net should be prefiltered through     *
        carbon to prevent the adsorption of
        foreign materials).  Drying requires
        about two days.

      b  Store carbon samples in one gallon
        paint cans, (tightly closed)

B  Solvent Extraction of Carbon

   It is necessary that blanks be run on all
   solvents and on the carbon used for col-
   lection of the sample.

   1  Packing the Extractors

      a  Filter paper at bottom of soxhlet.

      b  Glass wool (pre-extracted) three
        inches in depth to prevent carbon
        fines from passing into the pot. Add
        chloroform to wet the wool.

      c  Carbon is  added and packed. (N. B.
        do not pack too tightly)

   2  Chloroform Extraction

      a  Add chloroform - about two cylinder
        volumes.

      b  Extract for 35  hours.

      c  Siphon and blow the bulk of the chloro -
        form into the pot with air.

      d  Remove the flask  containing the
        chloroform solution from the system.
        Concentrate to 250 ml. by distillation
        and filter into a 300 ml. Erlenmeyer
        flask.  Evaporate to about 20 ml. on
        a steam bath with a stream of air and
        transfer to a tared 5  dram vial.  The
        remaining solvent is  evaporated at
        room temperature without an air jet
        and the weight  is obtained.

   3  Alcohol  Extraction

      a  Remove residual chloroform from
        the carbon by one of the following
        methods:
27-6

-------
                       Methods of Recovering Organic  Materials from Surface Waters
   1)  Blow warmed (40C) prefiltered
      air upward through the carbon for
      about 4 hours.

   2)  Leach the residual chloroform off
      the carbon with ethyl alcohol (95%)
      and distill off the chloroform
      alcohol mixture.   Repeat until
      virtually pure alcohol remains.

   3)  Remove the carbon from the
      soxhlet and air dry on trays.
      When dry,  repack into soxhlet as
      before  (Chloroform vapors must
      be disposed of).

b  Add sufficient ethanol (about two
   cylinder volumes) and extract for
   24 hours.

c  Concentrate the alcohol solution  as
   in the case of chloroform,  except
   that the final drying can be carried
   out on a steam bath with a stream
   of air.

The method listed first is most satis-
factory  for our work here, mainly
because a minimum of supervision is
required and chloroform vapors are
exhausted out the hoods.
C Extractable Materials

   1  Calculation of concentrations

      On most waters it is convenient to
      compute the recovery in parts per
      billion (ppb)(i. e.,  (ig/1) using the
      following formula.
                                /?
     h  -   grams recovered X 10
   PP   "    gallons filtered X 3. 785
   2  Infrared spectra
      Infrared spectra are routinely run on
      both the chloroform and alcohol extracts.
D  Special Applications

   Other solvents may find use in performing
   extractions.  If special applications are
   needed, a testing program is necessary
   to establish what solvents may best be
   used.

E  Adsorption and Desorption

   The effectiveness of adsorption and de-
   sorption varies for different materials and
   should be considered in interpretation of
   results.
                                                                                  27-7

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                       PRELIMINARY SEPARATION OF EXTRACTS

                                      R.  H. Burttschell*
 I  INTRODUCTION

 As a general principle it may be stated
 that the more sensitive modern analytical
 techniques (gas and other forms of chroma-
 tography, spectrophotometry, etc. ) require
 fairly pure samples to begin with;  and also
 as a general principle, it may be said that
 the more widely different the purification
 steps employed, the greater the degree of
 purification.

 Ion exchange, dialysis, crystallization,
 electrophoresis, etc. , are useful  but cannot
 be discussed here;  we will briefly cover
 only three techniques.

 A  Distillation

 B  Partition

 C  Adsorption
II  THEORETICAL BACKGROUND
                                                       layers are present,  irrespective of
                                                       their  relative amounts, the total vapor
                                                       pressure remains constant,  and the
                                                       system boils at a definite temperature."

                                                       Besides the familiar case of steam
                                                       distillation, non-polar organics  can
                                                       be co-distilled with  polar liquids, e. g. ,
                                                       insecticides with glycerol, and polar
                                                       compounds with non-polar solvents,
                                                       e. g. ,  mineral oil.   The co-distillation
                                                       can be done with superheated solvents
                                                       and under vacuum.   Where trace
                                                       quantities of one component are  in-
                                                       volved, there may not be a two-phase
                                                       system present and  the solvent vapor
                                                       serves only as a carrier  gas.  However,
                                                       here the solute can usually be easily
                                                       recovered  so  the method  is worth con-
                                                       sideration,  regardless of the mechanism.

                                                       In practical work the three important
                                                       points are  the stability of the sample,
                                                       its volatility,  and the ease of recovery
                                                       from the distillate.
A  Distillation

   1  Raoult's Law states that the partial
      pressure of A (PA) m an ideal mixture
      of volatile solvents is

      PA = mole fraction of A in liquid X
           vapor pressure of pure A at the
           temperature of the system.

      The total vapor pressure (which of
      course sets  the boiling point) is then
      PA+PB+  .  . .   This  is the basis
      for studies of distillation.   The ques-
      tion of non-ideal  solutions is too com-
      plicated to discuss.  Most physical
      chemistry texts go into it at length.

   2  Partially miscible liquids are a
      special case, often discussed as
      "steam distillation" although "co-
      distillation" is a  better term.  Quoting
      from Glasstone,  "As long as the two
                                                     3  Distillation from acid and basic solu-
                                                        tions may also be useful.  The principle
                                                        behind this will be discussed in the
                                                        solubility separation method.
                                                  B  Partition

                                                     Partition is the principle utilized in
                                                     liquid-liquid extraction, paper chroma-
                                                     tography  and gas  chromatography.   The
                                                     fundamental  law is the Distribution Law:
                                                     "A dissolved substance distributes  itself
                                                     between the layers of a two-layer system
                                                     so that at constant temperature the ratio
                                                     of the concentrations is also constant.
                                                     The Law is properly applied only to dilute
                                                     solutions  but a first approximation  to the
                                                     distribution ratio  can be obtained from
                                                     the  ratio of the  solubilities:

                                                                     K -
                                                                          Sw
-Chemist,  Chemistry & Physics Section, Basic and Applied Sciences Branch,  DWS&PC, SEC.
Reviewed December  1965.
CH.OTS.46a.4.65
                                                                                      21-1

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Preliminary Separation of Extracts
     K is a true constant but apparent dis-
     crepancies occur where the solute has
     different molecular weights in the two
     phases.   Benzole acid, for instance,  is
     largely  tjiCOOH plus some benzoate ion
     in water;  in benzene it is the  dimer
     (4>COOH)2. K then applies only to the
     species common to both layers, COOH.
     and ignores the dimer.

     Most texts on qualitative organic analysis
     contain  a great deal of practical infor-
     mation on solubilities, while the usual
     undergraduate physical chemistry texts
     cover the essentials of the theory.
  C  Adsorption

     There are two kinds of adsorption to be
     considered, physical (van der Waals)
     adsorption and chemisorption.  The
     theory of adsorption from solution is
     not as well understood as adsorption of
     gases but we can make a few comments.
     Physical adsorption depends on the
     relatively weak  van der Waals forces due
     to electrostatic  attraction of dipoles, it
     being assumed that non-polar molecules
     act as oscillating dipoles,  i. e. , the
     nuclei of atoms  and molecules form
     oscillating dipoles with the  electrons.
     Since the bonds  are weak,  adsorption can
     be made reversible under proper conditions.
     Chemisorption is thought of as actual
     chemical reaction and the resulting bonds
     are much more difficult to break.  Losses
     due to "irreversible adsorption" may
     therefore appear; this is particularly
     true  of carbon,  less so of silica and
     alumina.
 Ill  SOLUBILITY SEPARATION OF
     EXTRACTS

  In the next section we have described a
  laboratory procedure we have found very
  useful in handling carbon filter extracts
 ( CCE).   The extracts are split into acid,
 basic, and neutral fractions and the neutral
 fraction is further separated by adsorption
 chromatography.

 This procedure has been extremely useful
 where the fractions are  weighed and infrared
 spectra made.   However, where volatile com-
 pounds  are to be looked  for by gas chromato-
 graphy, it is almost imperative that a steam
 distillation step be included.  Otherwise the
 mass of heavy probably  polymeric material
 present causes much interference.

 Really good clean-up methods  are likely to
 be highly specific and need to be "tailor-
 made" to suit the situation.  Since this lecture
 is concerned only with "preliminary" puri-
 fication, we have omitted discussion of  precise
 analytical partition and  adsorption columns;
 thin-layer,  ion exchange, paper,  and gas
 chromatography; gradient elution methods,
 etc.  Such methods constitute a second and
 higher degree  of purification but ordinarily
 require that they themselves be preceded by
 a "rougher" primary purification.
IV  NOTE ON LOSSES OF VOLATILE
    COMPOUNDS
 It may not be generally recognized but it is
 quite true  that heavy losses of even moderate-
 ly volatile compounds occur if one tries to
 evaporate  off all the  solvent,  as when pre-
 paring to weigh an extract.  We have had
 losses of over 50% in attempting to carry
 out what we thought were very careful  evapora-
 tions of ether from 10 to 20 mg amounts of
 phenols.

 For this reason we suggest that no extract or
 fraction be evaporated down for weighing
 unless it is known to be  completely non-
 volatile.  This precaution becomes more
 necessary as the purity  of the sample in-
 creases because non-volatile impurities act
 as "solvents" to reduce  the amount of loss
 (according to Raoult's Law).
27-9

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           PROCEDURES FOR THE PRELIMINARY SEPARATION OF EXTRACTS

                           R. H. Burttschell and J.  J.  Lichtenberg*
 I  STEAM DISTILLATION OF EXTRACTS

 Steam distillation need be only a very simple
 procedure.   Put a gram or two of crude or
 partially purified sample in a small flask
 containing 50 -  100  ml of distilled water.
 Set up for ordinary  distillation and boil off
 most of the water.  If necessary,  add more
 water to the flask and continue distilling un-
 til the distillate has no trace of  cloudiness or
 a second phase  as it drips from the condenser.
 Transfer the distillate to a separatory funnel,
 extract with a suitable solvent,  and concen-
 trate to a convenient volume.  As  the product
 is relatively volatile,  do not try to evaporate
 to dryness if it  can  be avoided.  The non-
 volatile residue in the distillation  flask can
 also be recovered if necessary.

 If it is  desired to recover acids  (e. g., phenols
 in the 4-AAP colorimetric method), make the
 solution acid before distilling; the distillate
 will then contain only neutral and acidic sub-
 stances.  The neutrals can then be separated
 during  the extraction step.  Basic materials
 remaining in the still pot, e. g., aniline,  can
 then be recovered by making basic and dis-
 tilling over a second fraction.
II   SOLUBILITY SEPARATION OF EXTRACTS

 A  The organic contaminants from water as
    extracted from carbon or concentrated by
    liquid extraction ordinarily form an ex-
    ceedingly complex mixture for which there
    is no one satisfactory separation procedure.
    If the analysis is directed towards a single
    component, the procedure  may be designed
    for that purpose; otherwise a useful and
    generally applicable preliminary separa-
    tion may be made on the basis of relative
    acidities.
 B
By extracting an ether solution of the sam-
ple with water,  then with dilute hydrochlo-
ric acid, then sodium bicarbonate,  and fin-
ally sodium hydroxide, a separation into
water soluble, basic, strongly acidic, weak -
ly acidic, and neutral fractions  may be made.
                                                 The portion insoluble in ether may also be
                                                 recovered as an additional fraction.  This
                                                 method is obviously not suited to very vola-
                                                 tile  substances, nor  to further separation
                                                 of the water  soluble fraction, nor to sub-
                                                 stances unstable in the presence of water
                                                 or dilute acid or base; in addition, it must
                                                 be remembered that  substances whose par-
                                                 tition coefficients are not  extremely un-
                                                 favorable to  water may be present in sev-
                                                 eral fractions in varying amounts.

                                              C This procedure  constitutes one of the best
                                                 preliminary  steps in  analyzing any unknown
                                                 sample and may often profitably  be either
                                                 preceded or followed by steam distillation
                                                 (at various pH's) fractional crystallization,
                                                 etc.  Simple micro qualitative tests for ni-
                                                 trogen, halogens, sulfur,  phosphorus, etc,
                                                 are also often useful; for a more extended
                                                 discussion, see the texts mentioned in the
                                                 bibliography.

                                              D General

                                                 The  sample should be substantially free of
                                                 solvent.  The amount may vary consider-
                                                 ably but one-half gram is a very convenient
                                                 amount; as little as 100 mg or even less
                                                 may be used, but in this case there may
                                                 be large percentage errors.  Ethyl ether
                                                 has proved to be an excellent solvent al-
                                                 though often  not all the sample will dis-
                                                 solve in it; benzene or chloroform may be
                                                 used although these solvents are more
                                                 likely to cause troublesome emulsions.
Ill  LABORATORY DIRECTIONS

  A Solubility Separation Procedure

    Solution in Ether

    1  Weigh previously dried sample con-
       tained in a tared 50 ml beaker  (ap-
       proximately 0. 5  gm preferred). Also,
       weigh a 125 ml flask for the  Water
       Solubles (WS).
*Chemist, Chemistry & Physics Section, Basic and Applied Sciences Branch,  DWS&PC,  SEC
and Chemist,  Water Quality Section,  DWS&PC, SEC.   Reviewed December 1965.

CH. OTS.22b.4.65                                                                    2*7-10

-------
Procedures for the Preliminary Separation of Extracts,
   2  Dissolve the sample with a small
      amount of methanol (about one ml).
      Add the methanol dropwise and stir
      with a rigid wire until the sample
      reaches a syrupy consistency.

   3  Add 30 ml ether to the sample.  Not
      all will dissolve. Collect the Ether
      Insolubles (El) on a sintered glass
      funnel with suction and set aside for
      paragraph 4.   Pour the contents of
      the suction flask into a 125 ml separa-
      tory funnel equipped with a teflon stop-
      cock.   (Stopcock grease  will contami-
      nate the sample.)

   Ether Insolubles (El)

   4  Dissolve "El" previously collected on
      the sintered glass funnel with methanol.
      Wash funnel once with a  small volume
      of chloroform and collect in the suction
      flask.  Transfer filtrate to the original
      tared beaker with methanol.  Evaporate
      to dryness on a  steam bath and record
      weight for Ether Insolubles.

   Separation of the Water Solubles (WS)
                            (3>
   5  Shake the ether  solution three times
      with 15 ml portions  of distilled water.
      Drain the water layers into the weighed
      "WS" flask after each shaking. Evapo-
      rate the Water Soluble fraction to dry-
      ness on a steam bath with -a  jet of clean,
      dry air and record  weight for Water
      Solubles.

   Separation of Amine Fraction (B)

   6  Mark flask "HCl".   Shake ether solu-
      tion three times with 15 ml portions  of
      5% HCl and drain aqueous layers into
      HCl flask after  each shaking.  Make
      this aqueous  solution strongly basic
      by carefully adding NaOH pellets
      (about 30) or 25% NaOH. The solution
      becomes darker at this  point. Set a-
      side for back-extraction.

   Separation of Strong Acid Fraction (SA)

   7  Restore,  original ether volume to 30
      ml,  if necessary.  Mark flask "NaHCOa"
      Shake three times with 15 ml portions   
      of 5% NaHCOs and drain aqueous layers
      into NaHCOs flask after each shaking.
      Acidify aqueous solution in flask by
      adding sufficient concentrated HCl
      (dropwise because of liberation of CC>2)
      until strongly acid to litmus paper.
      About 4 ml is sufficient.   The solution
      becomes  cloudy at this point.  Set
      aside for back-extraction.

   Separation of Weak Acid Fraction (WA)

   8  Restore original ether volume to 30 ml,
      if necessary.  Mark flask "NaOH".
      Shake three times with 15 ml portions
      of 5% NaOH and drain aqueous layers
      into "NaOH" flask after each shaking.
      Wash once with 15 ml distilled water
      and drain this  into "NaOH" flask.

      CAUTION:  Tilt separatory funnel gently
                 a few times,  instead of shak-
                 ing the first portion, as e-
                 mulsions often occur.

      If a small amount of the water wash re-
      mains emulsified,  after draining,  add
      several drops  of saturated Na2SO4 so-
      lution and shake.  This may help to break
      the emulsion.  Acidify aqueous solution
      in flask with concentrated HCL until
      strongly acid to litmus paper.  About 8
      ml sufficient.  The  solution becomes
      cloudy at this point.  Set aside for back-
      extraction.

   Neutral Fraction  (N)

   9  Mark flask "N".  Pour the ether layer
      remaining in the separatory funnel in-
      to the flask "N". Add about 10 gm of
      anhydrous sodium sulfate, cap with
      aluminum foil  and allow to stand over-
      night to dry the ether solution.

B  Back Extraction

   Strong Acids (SA)

  10  Mark flask "SA".  Transfer NaHCO3
      extract from step 7 to separatory fun-
      nel and shake several times, care-
      fully, relieving pressure caused by
 27-11

-------
                                      Procedures for the  Preliminary Separation of Extracts
                                  WEIGHED SAMPLE
                                     add ether, filter
              Ether Solution
              extract with
  Ether Layer
 extract with HC1
  Ether Layer
extract with NaHCO3
                                           Residue
                                        evaporate, weigh

                                    ETHER INSOLUBLES (El)
                                      Water Layer
                                      evaporate, weigh
                                             I
                                  WATER SOLUBLES (WS)
                                                Water Layer
                                              Make basic, extract
                                                   with ether
              Water Layer
                 make acid
              extract with ether
                                    Ether Layer
                                    dry, evaporate
                                       and weigh
                                       BASES (B)
                              Water Layer
                                   Discard
           Ether Layer
           dry, evaporate
              and weigh
Water Layer
    Discard
          STRONG ACIDS (SA)
  Ether Layer
 extract with NaOH
                                                    Water Layer
                                                        make acid
                                                    extract with ether
  Ether Layer
   dry,  evaporate
     and weigh
               Ether Layer
                dry, evaporate
                  and weigh
        I
Water Layer
   Discard
  NEUTRALS (N)
              WEAK ACIDS (WA)
                                                                                   27-12

-------
Procedures for the Preliminary Separation of Extracts
      evolution of CO2.  Shake the NaHCO3
      extract, previously made acid, with a
      15 ml portion of ether.  Caution:  Re-
      lease  CC>2 during first shaking repeated-
      ly to avoid pressure build-up.

      Drain the aqueous layer into the NaHCC>3
      flask.   Pour the ether layer into the
      "SA" flask.  Return aqueous layer to
      separatory funnel and repeat, extraction
      two  more times with 15 ml portions of
      ether.

      After  all the ether layers have been
      collected in the "SA" flask, add about
      10 gms anhydrous sodium sulfate, cap
      with foil and allow to stand overnight
      to dry the ether solution.  Discard  the
      aqueous NaHCC>3  portion which should
      be almost colorless.

   Weak Acids (WA)
  11  Mark flask "WA".  Shake the NaOH ex-
      tract,  previously made acid, three
      times  with 15 ml portions of ether and
      collect in flask "WA" as  in step 10.
      Add sodium sulfate to dry,  cap with
      foil and allow to stand.  Discard aqueous
      NaOH  portion which should be almost
      colorless.

   Bases (B)

  12  Mark flask "B". Shake the HC1 extract,
      previously made basic, three times
      with 15 ml portions of ether and col-
      lect in flask "B".  Add sodium sulfate
      to dry, cap with foil  and  allow to stand.
      Discard aqueous HC1 portion.

C  Transfer

  13  Weigh four flasks and mark them "N",
      "WA",  "SA", and "B".  Record weights
      of each.  Transfer the corresponding
      dried ether solutions from the Na2SC>4
      into the weighed flasks by filtering
      through filter paper.

  14  Evaporate the  ether from the above
      fractions with  the aid of clean, dry cir-
      culating air and gentle heat on a steam
      bath.  The ether solutions should  be
      removed from the  air and heat before
      totally dry and allowed to dry spontane-
      ously to prevent loss of volatile com-
      ponents.  Record the weight of  the dried
      fractions.

D  Chromatographic Separation

  15  Weigh a 10 ml beaker and record weight.
      Dissolve the Neutrals in about 5 ml an-
      hydrous ether,  transfer most of the Neu-
      trals to the beaker and place the remain-
      ing few drops in a vial for infrared analy-
      sis.  Wash the (N) flask with ether and
      pour washings into vial also. Dry the
      Neutrals contained in the beaker by
      spontaneous evaporation and record
      weight.

  16  Weigh a set of 125 ml Erlenmeyer
      flasks and mark them Aliphatics, Aro-
      matics and Oxys. Record weights of
      each.

  17  Fill the chromatographic column with
      4 1/2" of silica gel and tap down to
      about 4".  Place the Aliphatics flask
      under the column. Add about 20 ml of
      iso-octane to wet the column.

   Aliphatics

  18  Before the iso-octane  reaches  the le-
      vel of the silica gel, add the Neutrals
      which have been previously adsorbed
      onto a small amount of silica gel by
      stirring in the beaker with a rigid
      wire.  Elute with 85 ml  iso-octane.
      Rinse the beaker with a  small portion
      and add to the column first.  Allow
      this volume to enter silica gel  before
      adding the remainder of the iso-octane.
      Collect the eluent in the Aliphatics
      flask,  evaporate to dryness with the
      aid of gentle heat and circulating air.

   Aromatic s

  19  Place the Aromatics flask under the
      column.  Elute column with 85 ml of
      Benzene-rinsing the beaker with a
      small portion and adding immediately
      as the previous eluent reaches the
      level of the silica gel.  Allow this vol-
      ume to enter silica gel before  adding
      remainder of benzene.  Evaporate
 27-13

-------
                                      Procedures for the Preliminary Separation of Extracts
                  CHROMATOGRAPHIC SEPARATION OF NEUTRALS

                                       NEUTRALS
                              Adsorb on Silica gel Column
         Elute with
          Iso-octane
        ALIPHATICS
 Elute with
  Benzene
AROMATICS
         Elute with
    Chloroform/ Methanol
            (1:1)
OXYGENATED COMPOUNDS
    with the aid of gentle heat and circu-
    lating air.  The Aromatics fraction
    should be removed from the air and
    heat before totally dry and allowed to
    dry spontaneously to prevent loss of
    volatile  components.
20  Place the Oxys flask under the column.
    Elute with 85 ml of a 1:1 methanol
    chloroform mixture - rinsing the beaker
    with  a small portion and proceed as
    before.  Evaporate to dryness with the
    aid of gentle heat and circulating air.

21  Record weights of the dried Aliphatics,
    Aromatics and Oxys.

    NOTE: (All chromatographic solvents
           should be redistilled before use)
          REFERENCES

          1  Shriner, Fuson and Curtin, "The Systematic
               Identification of Organic Compounds, "
               4th Ed. , John Wiley & Sons, New York,
               1956.
          2  Cheronis and Entrikin, "Semimicro Qualita-
               tive Organic Analysis, " Thomas  Y.
               Crowell Co. , New York, 1947.

          3  Cheronis, "Micro and Semimicro Methods, "
               Vol. VI of the series "Techniques of
               Organic Chemistry, " Arnold Weissber-
               ger, Ed. , Interscience, New York, 1954.

          4  Schneider, "Qualitative Organic Microanaly-
               sis, " John Wiley & Sons, New York,
               1946.
          These books deal principally with chemical
          methods of identification; Shriner, Fuson
          and Curtin and Cheronis and Entrikin are
          recommended for those new to the field. For
          instrumental analysis and quantitative work,
          see standard works in those fields.
                                                                                   27-14

-------
                        SURFACTANTS AND SYNTHETIC DETERGENTS

                                        R.  C.  Kroner*
  I  COMMERCIAL SIGNIFICANCE

  Synthetic detergents are a new class of
  organic chemicals  of extreme commercial
  significance.  In approximately 20 years sales
  have increased from a negligible amount to
  about 3. 8 billion pounds per year.   They are
  of public  health significance because almost
  every pound of material sold ultimately finds
  its way into a sewage treatment plant,  a
  surface water or a water treatment plant.
                 o
                 II
 C1nH_..  - O  - S  - O
   12  25         ||
                 O
                                  Na
   2  Cationic, in which the long chain por-
     tion of the molecule carries a positive
     charge:
 A Household users make up about 75% of the
    market.  Industrial users,  which are
    rapidly increasing, currently use the
    remaining 25%.

 B Household uses are well established.  In-
    dustrial uses include natural and synthetic
    fiber processing and  dyeing, fur and
    leather processing, paper making, brick
    and pottery processing,  electroplating
    and electrocleaning,  concrete preparations,
    rubber manufacture,  formulations as in
    soluble oils, insecticides, cosmetics, etc.


 II  NATURE  OF SURFACTANTS(7) (8)

 What are surfactants, synthetic detergents?

 A Surface active  agents are soluble organic
    materials which possess the property of
    altering the surface or interfacial pro-
    perties of their solutions to an unusual
    extent when present in low concentrations.
    Three types of surface active materials
    are presently in use.
       Anionic, in which the long chain
      ^portion of the molecule carries a
       negative charge:
                                                                     CH
C12H25  -    ?
            CH,,
                                       Cl
   3 Nonionic,  which does not ionize at all.
   C8H17
      -O-
C  A typical household detergent may contain
   the materials shown in Table  1.

D  The advantages of synthetic detergents are
   stability in low pH waters, no "scums"
   with hard  waters,  superior efficiency,
   variety of formulation, cheapness.

E  Anionics are used principally in household
   cleaners.   Cationics are used as sanitizers
   in laundering and dish-washing (hospitals,
   restaurants, taverns).  Nonionics are used
   as suds controllers but find principal usage
   in industrial applications.
*In Charge, General Laboratory Services,  Water Quality Section, DWSPC, SEC,  and revised by
Betty Ann Punghorst, Chemist, DWSPC Training Activities,  SEC.  Reviewed December 1965.
CH. DS.9b. 11.64
                                    28-1

-------
 Surfactants and Synthetic Detergents
                                          TABLE  1
CHEMICAL
Surface active agent
Sodium phosphate
Sodium sulfate
Sodium silicate
Methyl cellulose
Fatty amides
Sodium perborate
Perfumes, anti-oxidants
fluorescent dyes, etc.
%
20%
35%
20%
10%
1%
3%
10%
0.1%

FUNCTION
Reduce surface tension
Assist micelle formation,
pH control, metals com-
plexation
Additional electrolyte, builder
Prevents metal corrosion
Prevents redeposition of
soil particles
Foam stabilizer
Bleaching agent


F  Cationics and anionics react,  forming
   precipitates, effectively removing
   cationics from solution.  Since anionics
   are always in excess, cationics pose no
   problem in water systems.
G  Surface active properties are result of:
         64

hydrophobic portion
of molecule
                         SO  Na
                            o
                          hydrophilic portion
                          of molecule
   hydrophobic - from Greek, meaning
   "water fearing".

   hydrophilic - from Greek,  meaning
   "water loving".
UI  PUBLIC HEALTH SIGNIFICANCE
    OF SURFACTANTS(7)(8)

 Synthetic detergents are said to have adverse
 effects on water supplies and treatment
 processes.
 A Sewage treatment plants have experienced
    severe foaming problems, sedimentation
    difficulties, decrease in coagulation
    efficiencies, changes in biological oxidation
    processes.
 B Water treatment plants have experienced
    coagulation difficulties,  foaming and
    frothing at plant and in homes, taste
    problems,  etc.
28-2

-------
                                                        Surfactants and Synthetic Detergents  	
  C Natural surface waters may contain in-
    creased amounts of phosphates leading
    to production of algae growths.  Efficiency
    of oxygen transfer may be reduced.  Foam-
    ing may follow heavy rains or washouts.

  D A diversity of opinion exists as to the
    actual causes  of these  experiences.
IV  ANALYTICAL METHODS FOR
    ANIONIC SURFACTANTS

 None of the analytical procedures available
 are completely satisfactory.
 A Methylene Blue
          R-SO3Na +  methylene blue
                     R-SO3Na-MB
       The dye complex is soluble in chloro-
       form.  Remove colored chloroform
       layer; read for color.

    2  Interferences include NO ,  NOQ, CNS,
       proteins.
                                ,
                               t
                        (2)
 B Two Phase Titration

    1  Anion + cation - complex precipitate.
       Titrate anion with standard cation; excess
       cation  reacts with acid dye to form dye
       complex in solvent layer.

    2  Interferences by soap and protein are
       eliminated by pH adjustment.  Versene
       eliminates Ca and Mg effect.

                      / c\
 C Infrared Procedure

    Sample is treated with activated carbon
    which adsorbs organic material. Surfactant
    material can be dissolved differentially
    with proper solvent.  Extract analysis  with
    infrared will identify the particular sur-
    factant and can also be used for quantitative
    measurement.
V  LABORATORY PROCEDURE:  Measure-
   ment of Anionic Surfactants by Methylene
   Blue

A  Reagents

   1  Methylene blue solution - dissolve 0. 35
      gms methylene blue  in one liter of .01
      N sulfuric acid.

   2  Chloroform, C.P.

   3  Sulfuric Acid,  5N

   4  Stock ABS Solution, 1.00 mg/ml

   5  ABS Working Standard,  0.010 mg/ml


B  Glassware

   1  Separatory funnels, 250 or 125 ml

   2  Volumetric flasks, 50 ml

   3  Filtering funnels

   4  Pipettes, assorted sizes
C  Preparation of Standard Alkyl Benzene
   Sulfonate Solutions

   1  Weigh an amount of the reference ma-
      terial (obtain from Association of
      American Soap and Glycerine Producers,
      New York) equal to  1. 000 g ABS on a
      100 per cent active basis.  Transfer
      quantitatively to a 1.0 liter volumetric
      flask and add 500 ml of distilled water.
      Swirl gently until all of the powder is
      dissolved, let stand for one half hour
      or until most of foam breaks and then
      make up to mark with distilled water. Each
      ml of this solution contains one mg ABS.

   2  Working Standard:  Pipette 10.0 ml of
      the stock solution into a  1.0 liter volu-
      metric flask and make up to mark.   Each
      ml of this solution contains 0. 010 mg
      ABS.
                                                                                         28-3

-------
Surfactants and Synthetic Detergents
D  Procedure

   1 Add 0,  1.0  2.0,5.0  10.0 20.0 and
     25. 0 ml of working standard to separatory
     funnels and make up to 100 ml with dis-
     tilled water.  These standards contain
     0,  .01,  .02,  .05,  .10,  .20  and. 25 mg
     of ABS.

   2 Add 100 ml of each sample to a separatory
     funnel.

   3 Add 1. 0 ml of 5N sulfuric acid and 5.0
     ml of methylene blue solution to each
     sample and standard.  Mix well.

   4 Add 10 ml of chloroform to each
     funnel, invert and shake once a second
     for 25 seconds. Allow the chloroform
     layer to separate.

   5 Draw off the chloroform layer and
     filter through a plug of absorbent cotton
     into a  50 ml volumetric flask.  Repeat
     the extraction twice more, using 10 ml
     portions of chloroform,  collecting the
     extracts in  the same flask.

   6 Rinse the cotton plugs with chloroform
     into the  50 ml volumetric flask, make
       up to mark with chloroform, mix well
       and let stand for 5 to 10 minutes.
       Read the optical density of the Reagent
       Blank and Standards against chloro-
       form as a reference blank at 650 m|i  in
       a suitable photometer or spectrophoto-
       meter and prepare a standard curve.

       Read the optical density of each
       sample in a similar manner and calculate
       mg/1 of ABS in each portion.  Report
       all results to the second decimal place.
VI  SUMMARY

 Alkyl benzene sulfonate (ABS), an anionic
 surfactant  and important constitutent of
 syndets, is both a surf ace-active agent and
 a biologically "hard" substance.  The Public
 Health Service in its Revised Drinking Water
 Standards of 1962  has stated that ABS should
 not be present in excess of 0. 5 mg/ 1 in any
 water supply where a more suitable supply
 is available.   Various methods have been
 formulated for the detection of anionic sur-
 factants,  the most popular one being the
 methylene blue extraction procedure.
 28-4

-------
                                                    Surfactants and Synthetic Detergents
REFERENCES

1  Bibliography on Synthetic Detergents in
      Water and Wastes.  Public Health
      Service.  Robert A. Taft Sanitary
      Engineering Center (Basic and Applied
      Sciences Branch,  Division of Water
      Supply and Pollution Control) .   June,
      1964.

2  Edwards, Gail P., and Glnn, Martin E.
      Determination of Synthetic Detergents
      in Sewage.  Sewage and Industrial
      Wastes.   26: 945.  1954.

3  Hill, W. H.,  Shapiro, M. A., and Kobayashi,
      Y.  Determination of Alkyl Benzene Sul-
      fonate in Water.   Jour. Amer. Water
      Works Assoc. 54: 409-416.   1962.
5  Longwell J.,  and Maniece, W. D.   Deter-
     mination of Anionic Detergents in
     Sewage, Sewage Effluents and River
     Waters. Analyst. 80: 167.   1955.

6  Sallee, E.M., et al. Determination of
     Trace Amounts of Alkyl Benzene Sul-
     fonates in  Water.  Anal. Chem. 28:
     1822.   1956.

7  Sawyer, Clair N., and  Ryckman,  Devere
     W.  Anionic Synthetic Detergents and
     Water Supply Problems.  Jour. Amer.
     Water Works  Assoc.  49: 480-490.  19~57.

8  Task Group Report.  Characteristics  and
     Effects of  Synthetic Detergents.  Jour.
     Amer.  Water Works Assoc. 46: 751-
     774.  1954.
   Jones,  J. H.  General Colorimetric
     Method for Determination of Small
     Quantities of Sulfonated or Sulfated Sur-
     face Active Compounds.  Jour,  of
     Associated Official Agri. Chemist. 28:
     3987 1945.
                                                                                    28-5

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                               INFRARED INSTRUMENTATION
                                       D.  G. Ballinger*
I  INTRODUCTION

In infrared work the spectroscopist is using
a spectral region which is not visible to the
human eye.  The types of visual comparators
commonly used  in the laboratory cannot be
applied to measurements  in the IR. Thus the
analyst is completely dependent upon an elec-
trical system for his evaluations.

Because of the  specific  nature  of the  IR
spectra of most  substances, the full record-
ed spectrum, with its characteristic peaks
is generally used.  The complexity of the IR
spectrum rules  out the possibility of manual
plotting of absorption curves.  Sensitive re-
corders, having rapid response,are required.

The region generally examined extends from
2.0 - 15(1 (Fig.  1).  Some research instru-
ments are capable of scanning a much wider
range,  from 1.0 - 40^.   In this portion of
the spectrum energy levels are low and strong
absorption bands are found.
                                                  As in all analytical spectroscopy, the measure-
                                                  ment system involves a source of radiant
                                                  energy, an arrangement for placing the sam-
                                                  ple in the incident beam,  and a detector or
                                                  receptor for measuring the changes in energy
                                                  caused by absorption.
                                                 II  SOURCE OF RADIANT ENERGY

                                                  A  Nernst Glower

                                                     This type of element consists of a mix-
                                                     ture of rare earth oxides bonded into a
                                                     small rod.  When electrically heated this
                                                     source gives off infrared energy of the
                                                     desired wavelengths.

                                                  B  Globar

                                                     In many newer instruments a rod of bond-
                                                     ed silicon carbide  is used.   Like  the
                                                     glower, the energy emitted is in the de-
                                                     sired region of the spectrum.
-2   2  2
10 A 1 A 10 A In 10% 1 cm
!



f>
\
<
<
     GAMMA
      RAYS
                  X-RAYS
                                    ULTRA
                                    VIOLET
                                                VISIBLE
  MICRO- AND
 RADIO WAVES
                                                           INFRARED
                         Figure 1 - ELECTROMAGNETIC SPECTRUM
'-Supervisory Chemist,  Technical Advisory and Investigations Section,  DWS&PC,  SEC,
Reviewed December  1965.
 CH. MET. 13. 12.63
                                                                                      29-1

-------
 Infrared Instrumentation
C  Nichrome Wire

   A few IR instruments use an electrically
   heated nichrome wire as a source.

D  Monochromator

   In order to provide a spectrum for study
   the IR instrument must disperse the energy
   from the source into small increments and
   selectively direct these wavelength com-
   ponents through the sample. These  functions
   are accomplished by the  monochromator.
   Since the glass optics used in visual range
   instruments will not transmit infrared
   energy, a prism of another material must
   be used. (Fig. 2)  shows the optical ma-
   terials commonly used, with the effective
   range of each.

   In order to maintain constant energy level
   with changing wavelength, the slit is
   "programmed".  That is, the slit changes
   as the wavelength increases, compensating
   for the loss of energy at  the longer wave-
   lengths.
Ill  CELL ASSEMBLY AND                   ,
    CHARACTERISTICS

 A Geometry

    In most photometric instruments the
    radiant energy reaches the sample after
    being dispersed into selected wavelengths.
    In IR spectrophotometers it is possible to
    place the sample in the undispersed beam
    and then pass the beam through a suitable
    monochromator to the detector.  In the
    double beam instrument shown in Pig. 3
    the energy from the  source is split into
    two equal beams.  One beam passes
    through the sample.the other is unchanged
    and thus becomes a reference. The re-
    corder indicates the difference in energy
    between the two beams; that difference
    is the result of absorption of  radiant energy
    by the sample.

 B Cell Characteristics
    1  Materials

       The factors which govern the  selection
       of optical materials in the monochromator
                                             MICRONS

                                         10              ,  15
                           20
25
                    GLASS
                          .. QUARTZ
                          	LiF
                          	CaFr
                                                  NaCl
                               Figure 2 - OPTICAL MATERIALS
29-2

-------
                                                                Infrared Instrumentation
                     Figure 3 - I-R SPECTROPHOTOMETER
DETECTOR
                             MONO-
                         CHROMATOR
                                                                             SOURCE
                                                          SAMPLE
   also apply to cell materials.  See j ig. 
-------
Infrared Instrumentation
      filled by means of a hypodermic syringe.
      After filling,  the  ports are sealed with
      Telfon plugs.

C  Special Cells

   1  Smears

      When non-volatile materials are being
      examined, the sample can be smeared
      directly onto  a cell window, with or
      without a covering window.

   2  KBr Technique

      Crystalline solids cannot be examined
      directly,  due to light scattering by the
      crystals.  A technique has been develop-
      ed using potassium bromide, whereby a
      solid can be mixed with KBr and com-
      pressed into a very thin sheet.  Since
      the KBr is transparent in the IR, these
      discs permit  the examination of the
      solid sample.  Preparation of the KBr
      discs is difficult but  opens the way to
      the examination of a  wider range of
      organic and inorganic materials.

   3  Gas Cells

      Because of the high sensitivity of the
      IR Spectrophotometer, it is possible to
      obtain the spectrum of gases as well as
      liquids and solids.  Obviously the mole-
      cular density of gases necessitates a
      much longer light path.  Special gas
      cells have been developed with path
      lengths from  5 cm to 10 meters.  The
      5  cm cells have a single pass  light
     path, while the longer paths are obtained
     by multiple passes, as shown in Fig. 5.
IV  DETECTOR                            

 A  Theoretical

    Radiant energy in the IR region is actually
    heat radiation.  The absorption of energy
    at various wavelengths is the absorption
    of heat.   Thus an infrared detector is a
    heat-measuring device. The most com-
    monly used detectors are the thermocouple
    and the Bolometer. Although these  measure
    the ambient temperature as well as the
    signal, it is only  necessary to measure the
    difference between the sample beam and
    the reference beam.  Further, since ra-
    diant energy is being measured, small
    temperature differences in the sample
    have  no effect.
 B  Thermocouple

    The bimetallic junction of the thermo-
    couple is capable of measuring energy
    changes over the whole IR range.  Because
    a very rapid response  is required, special
    thermocouples have been designed for IR
    applications.
 C  Bolometer

    Certain metals have the property of high
    thermal resistivity. That is, the electri-
    cal resistance of the metal changes greatly
    with change in temperature. The bolo-
    meter consists of an element of such a
    metal mounted as a target in the IR beam.
    Changes in resistance, produced by energy
    flucuations,  are converted to electrical
    impulses and fed to the amplifier circuit.
 29-

-------
                                                   Infrared Instrumentation
Figure 5 -ONE METER GAS ABSORPTION CELL
     (Courtesy Perkin - Elmer Corporation)
                                                                    29-5

-------
                    INFRARED IDENTIFICATION OF ORGANIC COMPOUNDS
 4000 3000
100
2000
1500
                                               CM I
                               1000    900
                                                                         BOO
                                                                                    700
                    1      V      10     II
              WAVEICNOTH (MICRONS1
                                                                      I/
                                                                            1 t      14
                                                                                         15
SPECTRUM NO. //
SAMPLE



ORIGIN ~1

PURITY ^J
PHASE 
THICKNESS^A'^'V. *
LEGEND
1
) 	
DATE *:/> *?._ ..
OPERATOR ^'^ _.
REMARKS

0-CH^CH;,


in
t>
|



                                                     THC PERKIN-EIMER CORPORATION, NORWALK, CONN.
CH. MET. 19. 12.63

-------
 Infrared Identification
                                                    7 "^ 8      9     10
                                                    WAVELENGTH (MICRONS)
SPECTRUM NO. 9
SAMPLE
M'rjogei/zf^f


ORIGIM

PURITY **
PHASE 't'f'o
THICKNESS c if*
LEGEND
1
2
DATE ~- f-J-f
OPERATOR &J0
REMARKS
r-
-\
1 )
V

                                                                                                           1
                                                                                                            o
                    4000 3000
                   100
2000
1500
       THC PERKIN ELMFR COPPORATION, NORWAIK, CONN.

CM-'      1000   900      800        700
                         3      4     "5     67      8     9      10
                                                    WAVELENGTH (MICRONS)
                                                                              _   I	L	I   wf,ot)is>0
THICKNESS 02 ***___
LEGEND
1
).
DATE ^-/^-J'-f _
OPERATOR ^& . _
REMARKS
ft*"
(^S-rS
0
V
,
>
s,

'

                                                                   THE PERKIN-ELMER CORPORATION, NORWAIK, CONN.
29-7

-------
                                                                  Infrared Identification
 4000 3000

   1'4AJ,'yk'.J, l-lri - 1I -
2000
           1500
                     CM'
                         1000   900      800-
                                                           ?00
                               WAVELfcNGTH (MICRONS)
    SPECTRUM NO.___


    SAMPLE	  	 .  .
      ORIGIN.
                       MJRITY_.  '_! _
                          LEGEND
                                           DATE  ?--v.
                          LEGEND __ __.   -





                          2,  	


                          DATE  3/zz/Jy. _ __


                          OPERATOR  #~&
                                              REMARKS
                                                            '


                                                             Z
                                                             o
                                             THE PERKIN-EIMER CORPORATION, NORWAIK, CONN.

-------
Infrared Identification
                4000 3000

               loo1"1"""''1"'
2000
1500
                      CM-'
                     1000   900
                                                 800
                                                 700
                                               7     8      9      10     11
                                               WAVELENGTH (MICRONS)
SPECTRUM NO. j>
SAMPLE
dctrJirf


ORIGIN

PURITY ^
PHASE <7-


                                                                                                   COM
                                                                                                     -a
                                                                                                     O
                 4000 3000
2000
1500
                  THE PERKIN.EIMER CORPORATION, NORWALK, CONN.

           CM-'       1000    900      800        700
                                                     8      9     10     11     12     13     14     15
                                               WAVELENGTH  (MICRONS)
SPECTRUM NO._JI 	
SAMPLE



ORIGIK 	
PURITY -"V
PHASE ^rjL
THICKNESS ^*
LEGEND.
1
2
DATE f't ->?f . _
OPERATOR c:f<3. -
REMARKS^. 	
,* >*?*,
/-<-<.#,-! ",- '/I'-. ^
0--. u, < H. . tt, -i ,
7
                                                                                                   SS
                                                                                                     o
                                                             THE PERKIN.EIMER CORPORATION, NORWALK, CONN.
 29-9

-------
                                                                       Infrared Identification
                                     CM'       1000   900      800
                             700
                             .;:L
                             WAVELENGTH (MICRONS)
SPECTRUM NO. ?
SAMPLE



ORIGIN 	 .
PURITY ACT
PHASE *'(>"*
THICKNESS 0* w
If GtND. ...
1
7
DATE 4-a-j-r

REMARKS .. _.
we*-**
' V

                                                                                    'c
                                                                                     5

                                                                                     Z
                                                                                     O
                                            THE PERKIN-EIMER CORPORATION, NORWAIK, CONN
4000 3000       2000
                         1500
                                     CM-'
1000    900      800

        .-i-t-J j-4_i_J_L-t JL-L-J-l-^-
                5     6      7      8     9      10
                             WAVELENGTH (MICRONS)
                                                        II     12     13      14
SPECTRUM NO._j?
SAMPLE (4)



ORIGIN

PURITY Jcj
PHASE 
THICKNESS 6^/i^cv
LEGEND
1.
2
DATE ^-A-/?_
OPERATOR -&^
REMARKS

AU-ci'-^i. -*- t-X' -:>*
^"

                                                                                   f^2
                                                                                     Z
                                                                                     O
CH.OTS.lab.J.lj.S?
                                            THE rCRKIN-ElMER CORPORATION, NORWAIK, CONN
                                                                                                  20-10

-------
Infrared Identification
                                   2000
           1500
CM-'
                                                                    1000   900
                                                  800
                                       700
                                                 7      n      9     10
                                                 WAVELENGTH  (MICRONS)
                                                12     13     U    55
SPECTRUM NO._^: 	
SAMPLE



ORIGIN 	
PURITY <*."
PHASE &*
THICKNESS.,!/****- .
LEGEND, 	
1.
2.
DATE J-//-4-?
OPERATOR ^>"C -
LEGEND .
1
2
DATE a - //-s.?
OPERATOR P4
REMARKS 	



                                                                                                          O
                         CH.UrS.lob.l.li.SV
                                                                 THE PERKIN-EIMCR CORPORATION, NORWALK, CONN.
   29-11

-------
Infrared Identification
          4000 3000
rooo    900
800
                                                                                  700
                    4567           9     10    11     V,
                                       WAVELENGTH (MICRONS)
SAMPLF NO, 13
SOURCE pl^u ^"'fe "'-
LOCATION
DATE SAMPLED- . .. ...
TYPp oMipulir."

REMARKS


PHASP '-'vi'"^*
OPFRATOR <*?
DAT El v^-i^
*
.,3



|
                                                                                    r t/i w
                                                                                    o o >
                                                                                    O C 
                                                                                    J> a> TI
                                                                                    H o r-
                                                                                    o m m

                                                                                    z   r
                                                                                        o
          4000 3000
             	I . . . .
                                                                        800
                           700
                                       7     8     9     10
                                       WAVELNGTH (MICRONS)
CAMPLE NO H
SOURCE W-MET^VL wJiLik/e.
LOCATION
DATE SAMPLED
TYPp JWJIWICH-

REMARKS _

-
PHASE L|1UI-CL
OPERATOR "w
DATE ^M-J .
A-^'**
y XH-




                                                                                    i- u> u>
                                                                                    o o >
                                                                                    o c C
                                                                                    > a) -o
                                                                                    H o I-
                                                                                    o m m

                                                                                    z
 29-12

-------
                                                                      Infrared Identification
  4000 3000
                     CM-1
                                                 1000    900
                                               800
                                                700


                                WAVELENGTH (MICRONS)
9AMP| f NO IS'
SOURCE PURE BEWZVL ETOE
LOCATION
DATp ^AMPI FT}


REMARKS 	


PHA1F VW'C

DATE VC-J.3

v^^-ft










O
r>
5
z



Jl 4
?!
a 
n i
f1! r
i



  4000  3000
 100
2000
1500
CM-i
1000    900
800
700
U
  60
 i40
  20
                                                                       INFUACCMP ,3K^ 137.1281
                                7      8     9     10     11     12    13     14    15
                                 WAVELENGTH (MICRONS)
SPECTRUM NO. Ifc
SAMPLEJ^f1^^1-^ *CiO



ORIGIN

PURITY fyhE __
PHASE LIQUID
THICKNESS_iJiy[rL__
LEGEND
1
2.
DATE a-l'--J
OPERATOR__S^ __
REMARKS
tHjCH^CHj^NjCH^CMjCHtCt^



in

s
Tl


                                               THE PERKIN-ELMER CORPORATION, NORWAUC, CONN.
                                                                                          29-13

-------
                                    Infrared Identification
DATA SHEET - ORGANIC LABORATORY
SOLUBILITY SEPARATION
WEIGHTS
ORIGINAL SAMPLE
GM

BASES

GM
STRONG ACIDS

GM
WEAK ACIDS

GM
NEUTRALS

GM
REMARKS





CHROMATOGRAPHIC SEPARATION
OF NEUTRALS
WEIGHTS
ALIQUOT USED

GM
ALIPHATICS

GM
AROMATICS

GM
OXYS

GM
REMARKS





SUMMARY OF DATA
BASES
STRONG ACIDS
WEAK ACIDS
NEUTRALS
TOTAL RECOVERED
% RECOVERY
GM



GM
%

                                                         29-14

-------
Infrared Identification
                                    N. B. COLTHUP

 29-15

-------
                                     Infrared Identification
        SPECTRA-STRUCTURE CORRELATIONS
 ==*pMl=l|i
 j-	faj:jtfe==t:
fc^fei;:E:^lfe:
?
 :Hffi
 n
          -- ,T
         r=F
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p=i_t
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ife
ll.'ll 
 ,T
        s.J
 .1

*i
                      I
      f
                        I
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                 : .*;** # 
                 -JKi   i-

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                        :H:
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1

4
S


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1 M s
1 i
1 11 s"
H'l I-

Vs


5
^


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>
c





                       H
      IE S"e 
      IftPii;
   F'i'Jjij!.^
                       _
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                       j--i
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                                *"' '
                            nil

                            B1*
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                               i-.
                                 o*-
                                 Z6
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                                  . .
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                     3 I
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                                            I
                                            ri
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                  M *
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                  M >-(
                  ^ ^1
                                             01
                                             J:
                                            . o
                                              511
                                              C !
                                            nl 3
                                            Jd O
                                            0 ^
                                               29-16

-------
                  CHEMICAL OXYGEN DEMAND AND COD/BOD RELATIONSHIPS
                                        R.  J. Lishka*
 I   DEFINITION

 Chemical Oxygen Demand is an analytical
 parameter of pollution which measures the
 chemically oxidizable material in a liquid
 sample.

 A  A variety of terms have been used to
    describe this  parameter.

    1  OC   -     oxygen consumed

    2  COD  -     chemical oxygen demand

    3        -     complete oxygen demand

    4        -     dichromate oxygen demand

 B  The COD test may be  compared to other
    similar tests  that attempt to characterize
    materials by  "shotgun" procedures.

    1  "iodine number" -  for evaluating fatty
      acids

    2  "substances decolorizing perman-
      ganate" - used for  assaying reagent
      grade chemicals

    3  "chlorine demand" -  for evaluating
      oxidizable  materials  in water
II  A chemical oxidation demand test is
 needed for many reasons, chief among
 which are:

 A Chemical oxidation is comparatively
   rapid as contrasted to biological
   oxidation.

 B Chemical oxidation is not subject to as
   many variables (seeding, toxicity, etc.)
   as is a biological system.

 C The chemical procedure requires less
   equipment and is less expensive to run.
 D In the presence of high toxicity, the
    chemical procedure may be the only way
    to determine the organic load.
Ill  The concept of the COD is almost as old
  as the BOD.  Many oxidants and variations
  in procedure have been proposed, but none
  have been completely satisfactory.

  A Ceric  sulfate has been investigated, but
    in general it is not a strong oxidant.

  B Potassium permanganate was one of the
    earliest  oxidants proposed and until re-
    cently appeared in Standard Methods (9th
    ed.) as a standard procedure.  The re-
    sults obtained with permanganate were
    dependent upon concentration of reagent,
    time of oxidation, temperature,  etc. , so
    that results were not reproducible.

  C Potassium iodate or iodic acid is an
    excellent oxidant but methods employing
    this reaction are time-consuming and
    require very close control.

  D A number of investigators have used
    potassium dichromate under a variety of
    conditions.  The  method proposed by
    Moore at SEC is now accepted as the
    standard procedure because  of the
    reproducibility, ease of manipulation,
    applicability to a wide variety of samples,
    and the use of a stable, primary standard
    reagent.  *
IV  The present method for chemical oxygen
 demand has been thoroughly studied and
 statistically evaluated by replicate compari-
 son with other methods.

 A The procedure consists of refluxing a
    sample containing organic material with
    sulfuric acid and an excess of standard-
    ized potassium dichromate.  During the
*Chemist,  Analytical Reference Service, Training Program and revised by J. W.  Mandia, Chemist
DWS&PC Training Activities.  Reviewed December 1965.
CH. O. oc. 5d. 8. 65
                                        30-1

-------
 Chemical Oxygen Demand and COD/BOD Relationships
    reflux period the chemically oxidizable
    organic material reduces a Stoichio-
    metric equivalent amount of dichromate,
    the remainder of which is measured by
    titration with standard ferrous ammonium
    sulfate.  The amount of dichromate re-
    duced (amount of dichromate added -
    amount  of dichromate remaining =
    amount  reduced)  is a measure of the
    amount  of organic material oxidized.

 B  Factors to be observed in the proper con-
    trol of the reaction are as  follows:

    1  The potassium dichromate and ferrous
      ammonium sulfate reagents must be
      standardized.

    2  The volume of dichromate  solution
      used must be accurately measured
      (25.0 ml).

    3  The volume of sample must be accur-
      ately measured,

    4  The concentration of sulfuric acid in
      the refluxing  solution should be 50% by
      volume.

    5  Sufficient time should be allowed to
      secure complete oxidation  of sample,
      usually not more  than two hours.
V  As in the case of biological oxidation, not
 all organic compounds are oxidizable by wet
 chemical methods.

 A Some compounds are  completely oxidizable
   with no difficulty.  Common among these
   are sugars,  branched chain aliphatics,
   and substituted benzene rings.

 B Other compounds are not oxidized by this
   method, chief among  which are benzene,
   pyridine, and toluene.

 C Some compounds are  only partially
   oxidized, but the oxidation efficiency
   may be increased by the use of silver
   sulfate as a  catalyst in the refluxing
   solution.   Straight chain acids, alcohols,
   and ammo acids are examples  of compounds
    which can be completely oxidized with the*
    assistance of the silver sulfate catalyst.
VI  The COD test(1) measures not only the
 chemically oxidizable organic material but
 also any chemically oxidizable inorganic
 material (e. g. , chloride ion) contained in
 the sample.  Chloride  ion at a concentration
 of 200 mg/1 or more (10 mg Cl/50 ml sample)
 represents a positive interference in this
 procedure.

 A By actual measurement, the correction is
    (mg/1 C1X 0.23 = mg/1 COD).  This
    correction is not applied when the silver
    sulfate catalyst is used because of pre-
    cipitation of the silver as AgCl.

 B It has been established that chlorides  are
    not always quantitatively oxidized in the
    presence of organic matter.  In the pre-
    sence of high concentrations of ammonia,
    organic amine, or nitrogenous material,
    a continuous reduction of dichromate
    occurs.  The mechanism for this reduction
    is thought to involve a series of cyclic
    changes from chlorine to chloride through
    the formation of chloramines.  The addi-
    tion of  silver sulfate at the start of the
    digestion can lead to error because of the
    unknown degree of chloride oxidation.   In
    addition, much of the catalytic action is
    lost due to precipitation of the silver  ion.
    Furthermore,  in a  sample containing  a
    high concentration of chlorides,  the
    application of the chloride correction  may
    result in a negative value for the COD.

 C To overcome the difficulties presented by
    chlorides,  it was found that chloride could
    be eliminated from  reaction by a complex-
    ing technique using  mercuric sulfate.  *1)
    By the  simple  expedient of adding both
    sulfate and silver sulfate to the sample,
    interference from chloride is avoided,
    and the  catalytic action of the silver sul-
    fate is  retained.

 D COD Method for Highly Saline Waters

    The maximum COD that can be measured
    using a 50 ml sample and 25 ml 0. 25  N
    dichromate is  1,000 mg/1.
  30-2

-------
                                        Chemical Oxygen Demand and COD/BOD Relationships
    1   A sample containing 10 g/1 chloride
       (50% sea water) has a COD of 2, 300
       mg/1 due to chloride.

    2   When Ag2SO4 is used as a catalyst,
       chloride first must be removed.

         Ag2S04  + 2C1"	ix  2,AgCl,

       AgCl is not completely oxidized during
       the test.  A correction cannot be made
       for the AgCl which has not been oxidized.

    3   The dissociation constant of AgCl in
       distilled water is 1. 56 X 10'10".

    4   Hg++ in HgSO4 forms a chloride with
       a dissociation constant at 25C of
       2. 6 X 10"-^ The greater reduction
       of chloride COD occurs in the absence
       of Ag2SO4 catalyst.

    5   A correction factor of 0. 014 X mg/1
       Cl"  is applied for a 2 hour COD
       digestion using  10 mg HgSO4/mg
       chloride in the COD mixture  in the
       presence of lgAgSO4-


'II  It is possible to calculate the theoretical
 chemical oxygen  demand for organic com-
 pounds if the oxidation reaction is known.

 A  Sample calculation for glucose;
   B  Sample calculation for phenol:

      1. 000 g         X

      C6H5OH  +  7 O2>  6CO2  +  3 H2O

      94 g     224 g

                      1.000 X 224 _ 2 383
                                    Oxygen
                                                  Theoretical COD =
                                                                         94
   1.000 g       X
    C6H126
   180 g   (6 X 32)  g
                           C
                                    H2
     X  -   -
Where

   180
    32
 1. 000

     X

            molecular weight of glucose
            molecular weight of oxygen
            experimental weight (in g) of
            glucose
            weight of oxygen required to
            oxidize 1. 000 g of glucose
VIII   It is not possible to establish fixed
   relationships between BOD and COD measure-
   ment until a particular sample has been
   characterized by both parameters.

   A  If the sample is primarily composed of
      compounds that are oxidized by both
      procedures (BOD and COD) a relation-
      ship may be established.

      1  The COD procedure may be substituted
        (with proper qualifications) for BOD.

      2  The COD may be used as an indication
        of the dilution required for setting up
        BOD analysis.

   B  If the sample is characterized by a pre-
      dominance of material that can be chemi-
      cally oxidized, but not biochemically,
      the COD will be greater than the BOD.
      Textile wastes, paper mill wastes, raw
      sewage, containing high concentrations
      of cellulose have a high COD,  low BOD.

   C  If the situation as in item VIII B (above)
      is reversed,  the BOD will be higher than
      the COD.  Distillery wastes or refinery
      wastes may have a high BOD,  low COD.
 IX   The present standard method for COD is
   commonly used for characterizing samples
   of high organic content.  However,  the
   method with some alteration may be used for
   analysis of samples containing low  organic
   content, i. e. , from 5 to 50 mg/1 COD.

   A  The normality of potassium dichromate
      and ferrous ammonium sulfate is reduced
      from 0. 25 N to 0. 025 N.
                                                                                       30-3

-------
 Chemical Oxygen Demand and COD/BOD Relationships
 B  Special precautions are taken to insure
    replicable results:
    1   Condensers are plugged with glass
       wool to eliminate  airborne dust.

    2   Distilled water used for dilution must
       be of extremely good quality.

    3   More indicator must be used to obtain
       clean end point.

    4   High quality sulfuric acid, with no  ^^
       appreciable demand, is required.    "^ <\
X   Using the revised COD procedure for
 stream samples, estimates of the probable
 BOD ratio at a particular stream point may
 be made from a  series of previous repre-
 sentative COD/BOD ratios.

 A  In stream surveys, the  COD/BOD ratios
    from representative sampling points
    give information on general stream condi-
    tions, location of pollution, ability of the
    stream to oxidize the waste load and
    relative degree of biological stability.
XI  The low-level chemical oxygen demand
 test can only be  used for samples having a
 COD < 100  mg/1.  For stronger wastes, the
 standard test must be used.
 REFERENCES

 1  Dobbs, Richard A. ,  and Williams,
       Robert T.  Elimination of Chloride
       Interference in the Chemical Oxygen
       Demand Test.  Anal. Chem.  35:1064.
 /'"    1963.

 2  Standard Methods for the  Examination of
       Water and Wastewater.  llth Edition.
       American  Public Health Association,
       American  Water Works Association,
       Water Pollution Control Federation,
       1960.

 3  Cripps,  J. M. and Jenkins, D.  A COD
       Method Suitable for the Analysis  of
       Highly Saline Waters,  JWPCF  36,
       1240-1246.  1964.
  30-4

-------
            LABORATORY FOR CHEMICAL OXYGEN DEMAND DETERMINATION
                                        R.J.  Lishka*
 I   REAGENTS AND EQUIPMENT

 A  Potassium Dichromate Solution - 0. 25N

 B  Ferrous Ammonium Sulfate Solution 0. 25N,
    Approximately

 C  Sulfuric Acid -  Concentrated

 D  Mercuric Sulfate - Analytical Reagent

 E  Silver Sulfate - Analytical Reagent

 F  o-Phenanthroline Ferrous Indicator
    (Ferroin)

 G  Flasks, Erlenmeyer,  500 ml,  24/40
    E Joint

 H  Condenser, Friedrichs Reflux 24/40
    IB Joint

 I   Burette, 50 ml

 J   Glass Beads or Porcelain Chips


II   PROCEDURE

 A  Measure 50 ml of sample or aliquot diluted
    to 50 ml with distilled water,  and place
    in 500  ml Erlenmeyer flask then add:

    1  1 gram mercuric sulfate
   2  5 ml concentrated H^SO  - swirl to
      dissolve mercuric salt.
   3  25 ml 0.25 N
   4  70 ml concentrated H^SO  (Cautiously)

   5  0. 75 gram Ag SO

   6  Several glass beads or porcelain chips
B Mix well by swirling flask.
 C  Connect flask to condenser and reflux for
    two hours.

  D Wash down the condenser with distilled
    water and cool to room temperature.

  E Add 10 drops of o- phenanthroline ferrous
    indicator and titrate to a red end point
    with standardized ferrous ammonium
    sulfate solution.

  F Carry a  blank, consisting of 50 ml of
    distilled water, through the same
    procedure.

  G Standardization of ferrous  ammonium
    sulfate solution
    1  Pipette 25 ml of 0. 25 N K  Cr O  into
       a 500 ml Erlenmeyer Mask.

    2  Add 250 ml of distilled water.

    3  Add 50 ml cone. H  SO
                          ri

    4  Add 10 drops of o-phenanthroline ferrous
       indicator and titrate to a red end point.

    5  Calculation
 Normality of Ferrous soln. =
	25 X 0.25	
ml ferrous soln.
Ill  CALCULATION OF COD
                                                COD mg/1 =
            a - b X normality of ferrous soln.
            	X 8000	
                     ml of sample
    a  =  ml  ferrous ammonium sulfate used
          for blank

    b  =  ml ferrous ammonium sulfate  used
         for sample
*Chemist, Analytical Reference Service, Training Program, SEC.  Reviewed December 19G5.

CH. O. oc.lab. 1. 12.64                                                                 30-5

-------
 Lab.  for COD Determination
IV  SPECIAL DIRECTIONS FOR
    LOW-LEVEL COD

 A Use 0. 025 N potassium dichromate
    solution and  0.025 N ferrous ammonium
    sulfate solution instead of the 0.25 N
    reagents.  The procedure and calculation
    are unchanged.

 B The ferrous ammonium sulfate solution
    is not stable and must be standardized
    daily.

 C Keep the  reflux apparatus assembled
    when not  in use.

 D The outlet tube of the condenser should
    always be lightly plugged with glass
    wool,  both during storage and when in use.

 E Before disconnecting the flask,  wipe the
    condenser and the flask neck with a damp
    cloth to remove dust particles.

 F Periodically, the glass apparatus should
    be steamed out to remove trace  organic
    contamination,  using the following
    procedure:
   1  Add 50 ml distilled water to the flask.

   2  Carefully add 50 ml cone,  sulfuric
     acid and mix thoroughly.

   3  Connect the flask to the condenser but
     do not turn on the water supply.

   4  Apply heat to the flask until the acid
     mixture boils and steam emerges from
     the condenser.

   5  Remove heat, cool, and discard the
     acid mixture.
REFERENCES

1  Dobbs, Richard A.,  and Williams,
      Robert T.  Elimination of Chloride
      Interference in the Chemical Oxygen
      Demand Test.  Anal.  Chem.  35; 1064
      1963.

2  Standard Method for the Examination of
      Water and Waste water,   llth Edition.
      APHA. AWWA. WPCF.   1960.
 30-6

-------
                    INTRODUCTION TO GAS-LIQUID CHROMATOGRAPHY
                                    Betty Ann Punghorst*
 I  INTRODUCTION

 A  Definition

    Gas-liquid chromatography is an analytical
    method for the separation and identification
    of a mixture of volatile (usually organic)
    components in a sample.  As with any
    chromatographic technique the column
    consists of two phases,  the immobile or
    stationary phase (a liquid on an inert solid
    support), and the mobile phase (an inert
    gas).  The column functions to separate
    the sample components because they have
    varying vapor pressures and affinities for
    the stationary phase.  In many ways  the
    column behavior resembles that of
    fractional distillation.  The partition which
    occurs between the mobile and immobile
    phases will thus cause the components to
    proceed through the column at varying
    rates.  The separation is recorded and
    quantitated by the detector system.

 B  Advantages

    1  GLC can be used to separate compounds
      of similar boiling points which cannot
      easily  be separated by distillation. (See
      Table 1)

    2  GLC can be extremely sensitive; for
      example, using the  electron capture
      detector it is possible to "see" pico-
      gram (10~12) quantities.

     Table 1. SEPARATIONS BY GLC
      Compounds
3- Methylcyclohexene
  (B.P.  104C)  and
  4-Methylcyclohexane
  (B.P.  103C)

Cyclohexane (B. P.
  80. 8C) and Benzene
  (B.P.  80.2C)
   Reference
Aerograph Research
  Notes (Spring 1964)
Chromosorbe News-
 letter (FF-104)
                           C Disadvantages

                             1  Due to the extreme sensitivity possible
                                it is often necessary to apply extensive
                                clean-up techniques.

                             2  The many variables of the technique
                                require a skilled analyst.
II   COMPONENTS OF A GAS
    CHROMATOGRAPH (See Figure 1)

 A  Gas Supply

    The mobile phase (carrier gas) trans-
    ports the sample components through the
    column into the detector.  The type of
    gas used varies with the detector (See
    Table 2.)

 B   Injector

    Liquid samples are manually introduced
    into the heated injector block through a
    rubber septum by means of a syringe.
   Automatic liquid injectors as well  as in-
    jection systems for solid and gaseous
    samples are commercially available.

 C  Column

   The vaporized sample  enters the column
   which can be glass or metal and of varying
   length (I1 - 20') and diameter (1/8" - 1/4").
   The column is packed with the stationary
   (immobile) phase and contained within a
   constant temperature oven.

    1  Solid support

      The solid support should have a  large
      surface area yet be  inert  so that active
      sites will not cause  adsorption of sample
      components.  Diatomaceous earths,
      teflon and glass beads have been used.
      (See Table 3.)
*Chemist,  DWSPC Training Activities, SEC.

CH. MET.cr.5. 12.65
                                                              31-1

-------
Introduction to Gas-Liquid Chromatography
                                                               PRESSURE
                                                               REGULATOR
                   AUTOMATIC STRIP
                   CHART RECORDE
                                                             0S1LICOME RUBBER
                                                             STOPPERS
                                                             1/16" DIAMETER
                                                             S.S.TUBING
                  Figure 1.  COMPONENTS OF A GAS CHROMATOGRAPIT
          Table 2.  CARRIER GASES
        Detector
 Thermal conductivity

 Microcoulometric

 Flame ionization
 Electron capture
                         Carrier gas
                      Helium (Purified,
                        Grade A)

                      Helium (Purified,
                        Grade A)

                      Hydrogen (Purified)

                      Nitrogen or a mixture
                        of 95% argon and 5%
                        methane (Purified)
         Table 3.  SOLID SUPPORTS
        Support
Chromosorb P
 (Diatomaceous Earth)

Chromosorb W
 (Diatomaceous Earth)

Chromosorb G
 (Diatomaceous Earth)

Chromosorb T
 (Teflon)
   4.8


   1.2


   0.5


7.0-8.0
                        2  Stationary liquid

                          The separation and partition occurring
                          in the column is directly affected by the
                          choice of stationary liquid.   For ex-
                          ample,  in the separation of benzene
                          (B. P. 80. 1C) and cyclohexane (B. P.
                          80. 8C),  the choice of a non-polar phasi
                          such as hexadecane results in benzene
                          preceding cyclohexane off the column.
                          However, if a more polar phase such as
                          benzylbiphenyl is chosen cyclohexane
                          precedes benzene.   Table 4 shows  some
                          typical stationary liquids and their uses
                          (NOTE:  One requirement for any liquid
                          is that it  have a high boiling point so  tha
                          it will not boil off the  column)
                     Surface area (m2/gm)      D Detector
                                                    The detector or brain of the gas chroma-
                                                    tograph senses and measures the quantity
                                                    of sample component coming off the columr
                                                    The detector should be maintained at a
                                                    temperature higher than the column so that
                                                    condensation does not occur in the detector
                                                    block.  Several types of detectors are in
                                                    use today.
                                                  *Reproduced (with permission) from Chemist
                                                  (37:11, p.  13. November 1964).
31-2

-------
                                               Introduction to Gas-Liquid Chromatography
                           Table 4.  STATIONARY LIQUIDS
                   Stationary liquid
      Used to separate
           Silicone Oils QF-1,  Dow Corning
            200, and Dow 11

           Silicone Oil  SE-30

           Benzyl-Cyanide-Silver Nitrate

           Polyethylene Glycol
           Cyano Silicone
Chlorinated hydrocarbons
pesticides
Homologous series of n~ alkanes
Homologous series of olefins
Amines
Steroids
1  Thermal conductivity

   This detector consists of a Wheatstone
   bridge two arms of which are thermal
   conductivity cells each containing a
   small heated element. When only carrier
   gas is flowing through both the  sample
   cell and reference cell, the resistance
   of the heated element is constant in both
   cells.  The bridge remains balanced and
   baseline is recorded.  However,  when
   carrier gas plus sample component enter
   the sample cell, the thermal conductivity
   in that cell changes thus also producing
   a change  in the  resistance of the heated
   element.   The bridge becomes  unbalanced
   and a peak is recorded.  The main dis-
   advantage of the TC cell in water pollution
   work is its lack of sensitivity.

2  lonization detectors

   a  Flame

      This detector consists of a flame
      situated between a cathode and anode.
     As carrier gas alone burns,  some
      electrons and negative ions are pro-
     duced  which are  collected at the
      anode  and recorded as baseline.
      When carrier gas plus sample com-
     ponent are burned, more electrons
     and negative ions are produced which
      result in a peak  on the recorder.
      The detector is capable  of "seeing"
     nanogram quantities of organic com-
     pounds; however, the detector is
      sensitive to all organic compounds.
      This lack of specificity produces dis-
      advantages in the analysis of water
            extracts which contain a variety of
            naturally occurring organics.

         b  Electron capture (See Figure 2)

            This detector consists of a radiation
            source (e.g., tritium) capable of
            producing  slow electrons in a carrier
            gas such as nitrogen. The electrons
            collected at the  anode are recorded
            as  baseline.   When sample com-
            ponents which have an electron
            affinity (e.g., chlorinated hydro-
            carbons) enter the detector, electrons
            are "capture".  The  subsequent de-
            crease in current is  recorded  as a
            peak.   The detector has the advantage
            that it is extremely sensitive (pico-
            gram  range) and is somewhat selective.

         c  Thermionic

            A recent adaptation of the flame
            ionization  detector shows promise
            for the specific  analysis of organic
            phosphorus compounds.   The cathode
            of the  conventional flame ionization
            detector is coated with sodium salt.
            When  compounds containing phos-
            phorus emerge from the column,  they
            give 600X  the response with this de-
            tector as with the conventional flame.

      3  Microcoulometric

         This highly specific detector consists
         of titration cells for the measurement
         of chloride-containing and sulfur-
         containing compounds.  The sample
         component emerging from the column
                                                                                  31-3

-------
 Introduction to Gas-Liquid Chromatography
                          GAS EXHAUST
               RADIOACTI VE
                 TRITIUM 	
                  FOIL
                                 -tt-ANODE

                                        TO
                                        ELECTROMETER
             ELECTROMETER
                                                      COLUMN
                                             LOSSOFe"
                                                        REDUCES CURRENT
            Figure 2.  ELECTRON CAPTURE DETECTOR (Wilkens Instrument Co.)
       is combusted to produce HC1 or SO2>
       respectively.  HC1 is continuously titrat-
       ed by silver ions present in the  cell; the
       amount of current required to regenerate
       these silver ions is recorded as a peak.
       The system for sulfur containing com-
       pounds is analogous except that  SO2 pro-
       duced is  continuously titrated by 1% which
       is subsequently regenerated.  Although
       less  sensitive (by approximately a factor
       of 10) than electron capture, this de-
       tector is finding wide use in pesticide
       analysis.

 E Recorder

    The  recorder system registers the response
    of the detector to sample components.  In
    the case of ionization detectors,  it is often
    necessary to employ an electrometer in
    order to amplify the  small current changes.
    Expensive integration and digital read-out
    equipment is also available to facilitate
    measurement of peak areas.
Ill  QUALITATIVE ANALYSIS

 A Retention Time

    The retention time of a sample component
    is defined as the time it takes for that
   component to travel through the column.
   There are a number of variables which
   affect the  retention time  of a compound.

   1  Physical parameters of column
      operation

      a  Column length

      b  Column temperature

      c  Carrier gas flow rate

   2  The nature and amount of stationary
      liquid itself.

   For a given set of column conditions, a
   specific compound will have a specific
   retention time (see Figure 3 and Table  5)
   Various column and detector combination,
   can be used to confirm identification.

B  Retention  Volume

   Retention  volume is defined as the total
   volume of gas required to move a com-
   ponent through the column.
RETENTION
VOLUME (RT
= RETENTION X FLOW
  TIME (RT)      RATE
  31-4

-------
                                                     Introduction to Gas-Liquid Chromatography
                                            i	1	1
                                          SAMPLE 5 iJ.LofStand.inl Pestnulc- Mix-
                                                 ture (1 ngo! each Pestici
                                          COM MN Length-O1 X6 mm
                                                 Stationary Phase - 10 ' DC 200
                                                 on Anakrom ABS (00 /100 Mesh)
                                                 MobilePhn.se- ISOml/minN?
                                                 Temperature-2 10C
                                      5    7     9     11
                                       TIME (IN MINUTES)
                   Figure 3.  GAS CHROMATOGRAM OF PESTICIDE MIXTURE
  C  Relative Retention Times and Volumes

     It is possible to interpret data more easily
     by reporting retention data relative to a
     particular compound (e.g., aldrin as in
     Table 5).
IV  QUANTITATIVE ANALYSIS

 A Measurement of Peak Area

    The quantity of sample component present
    is directly proportional to the area under
    its peak.  (NOTE:  This  assumption can
    only be made if it has been previously
    determined that a linear response is ob-
    tained in the range under study.)  The
    following are a few of the ways in which
    this area can be measured.
   1  Planimeter

   2  Calculation of area (see dieldrin peak
      in Figure 3)

   AREA  = peakheight X  peak half-width

   3  Disc integrator

B  Measurement of Peak Height

   With the  electron capture detector it may
   be possible  to use peak height for quanti-
   tative measurements where the following
   conditions are  met.

   1  A steady baseline is obtained.

   2  Retention times can be reproduced
      from one injection to the next.
                                                                                           31-5

-------
Introduction to Gas-Liquid Chromatography
                        Table 5.  RETENTION DATA FOR FIGURE 3
Pesticide
Heptachlor
Aldrin
Heptachlor Epoxide
Dieldrin
Retention time (R )
3. 3 minutes
4.2
5.3
7.7
Relative retention
time
0.79
1.00
1.26
1.84
V  SUMMARY

The basic components of a gas chromatograph
have been described.  Elementary aspects of
quantitative and qualitative analysis are
presented.
BOOKS
     Dal Nogare, S., and Juvet, R. S.,  Jr.
        Gas-Liquid Chromatography. New
        York:  Interscience.   1962.
   2  Littlewood,  A. B. Gas Chromatograph;
        New York:  Academic Press.  1962
NEWSLETTERS

   1 Aerograph Gas Chromatography News-
        letter.  Wilkens Instrument and Re-
        search, Inc., P.O. Box 313, Walni
        Creek,  California.

   2 F &  M Gas Chromatography Newslette
        F & M Scientific Corporation. Stan
        Road and Route 41, Avondale, Pa.
31-6

-------
                           POLLUTION PROBLEM OF PESTICIDES
                                    Betty Ann Punghorst*
I  NATURE OF PESTICIDES

A  Classification

   Pesticides include insecticides, herbicides,
   rodenticides, miticides, nematicides, and
   fungicides.  They can be classified accord-
   ing to their origin.

   1  Mineral origin

      These include arsenicals and inorganic
      compounds containing sulfur, copper
      and fluorine.

   2  Botanical origin

      These include nicotine, pyrethrum and
      red quill.

   3  Synthetic origin

      a   Insecticides

         1) Chlorinated hydrocarbons

           These  compounds all contain
           chlorine,  hydrogen and carbon
           (see Figure 1).  A few such as
           dieldrin and endrin also contain
           oxygen.  Otherwise, they vary
             widely in their chemical structure
             and activity.  They affect the
             central nervous system; however,
             the basic mode of toxic  action is
             not known for any of them.

          2)  Organic phosphorus compounds

             These  compounds are derivatives
             of phosphoric acid (see  Figure 2)
             and are characterized by similar
             structure.  Their mode of toxic
             action  is to interfere with
             cholinesterase enzyme activity.

       b  Phenoxyalkanoic acid herbicides

          These compounds are similar to
          chlorinated hydrocarbons;  however,
          they are classified separately be-
          cause they also contain free carboxyl
          groups.  Examples  of such compounds
          are 2,  4D, 2, 4,  5-T and Silvex.

       c  Miscellaneous compounds  (e. g.,
          carbamates and dithiocarbamates)

  B History of Use and Control

    1  In 1000 B. C. , Homer first used sulfur
       as a fumigant for pest control.
                                 H      H
            Cl-C-CI
              Cl
              DDT
                                                ci
Cl
                                                                      Cl
                                                                                 Cl
                                 Cl

                              LINDANE
                   Figure  1.  CHLORINATED HYDROCARBON PESTICIDES
*Chemist, DWS&PC Training Activities, SEC.

WP.PES. 2b. 12. 65
                                      32-1

-------
Pollution Problem of Pesticides
       '"'Ml
               P	O
                                                CH30
                                               CH30
                                                                         O
     C2H5
                                                                    H
                   C - C - O - C0H
                   |               2  5
                  HC - C - O - PH.
                                    25
                                                                         O
                   PARATfflON                          MALATHION
                       Figure  2.  ORGANIC PHOSPHORUS PESTICIDES
   2  The insecticidal properties of DDT
      were discovered in 1939.

   3  Organic phosphorus compounds first
      appeared on the market in 1945.

   4  The production of synthetic organic
      pesticides has skyrocketed from
      0 Ibs. in 1942 to 772 million Ibs.  in
      1963. A ten-fold increase in pesticide
      output is predicted in the next 20 years.

   5  This large production output of toxic
      compounds has necessitated govern-
      mental programs of control.

      a  The original programs were designed
         to evaluate mostly short-term effects
         (acute toxicity).

         1)  1947 - The Federal Insecticide,
           Fungicide  and Rodenticide Act
           required proper labeling of all
           formulations containing pesticides.

         2)  1954 - The Miller Amendment to
           the Federal Food, Drug and Cos-
           metic Act of 1938 required that
           tolerances be established for
           pesticide residues on crops.

      b  In recent years, concern has arisen
         over long-term effects and the
         biological magnification of pesticides
         in the environment.

C Gains from Use

   1  Promotion of health

      a  Directly through the control of
         vector-borne diseases (e. g. , malaria).
II
      b  Indirectly through increased and
         improved agricultural production.

    2  Elimination of nuisances.
PESTICIDES AS A WATER POLLUTION
PROBLEM
 A  History

    1  The first awareness that synthetic
      pesticides could be a pollution problem
      in water occurred in 1950  when extensive
      fish kills happened in 14 streams
      tributary to the Tennessee River in
      Alabama.  These kills were caused
      by insecticides washed from cotton
      fields. <2)

    2  In 1954, Tarzwell and Henderson con-
      firmed  that insecticides could run off
      soil with rainwater.  They did this by
      applying clay granules containing 11%
      dieldrin to a measured grassy sod
      slope at a rate of 4. 66 Ibs. per acre
      and then assaying the dieldrin recovered
      in the runoff.(2)

    3  In 1959, the PHS established a Pesticide
      Pollution Project under the direction of
      H.  Page Nicholson in Atlanta, Georgia/2'

    4  Fish kills occurring in the lower
      Mississippi in the winters of 1960,
      1961, 1962 and 1963 have  been attributed
      to synthetic pesticide pollution.  Less
      than one ppb (water concentration) of
      endrin  was responsible for the kills.
 32-2

-------
                                                               Pollution Problem of Pesticides
B  Mode of Entrance into Water

 L- 1  Pesticides may be directly applied to
       water supplies for one of the following
       purposes.

       a  To control aquatic insects

       b  To control algal growths

       c  To poison fish in order to permit
          restocking with desired varieties.

 __,,  2  Industries may discharge liquid wastes
       containing pesticides.

 ^ 3  Runoff of pesticides from agricultural
       lands and forests is dependent on
       several factors.

       a  Solubility of the pesticide in water

       b  Persistence of the pesticide in the
          soil which in turn is dependent on the
          pH and temperature of the  soil.

       c  Quantity  of pesticide applied to the
          soil.
      d  Formulation of the pesticide

      e  Method of application of pesticide

      f  Slope of the land

      g  Soil characteristics

      h  Volume  and intensity of rainfall

      i  Soil conservation practices


C  Effects

   1  Acute toxicity

      a  An estimated 150 human fatalities
         occur annually in the United States
         from pesticides.  (Note: this is
         about the same  death rate as that
         due to aspirin).
                         (4)
      b  Bioassay studies   confirm that
         many fish are very sensitive to
         synthetic pesticides (Table  1).
               Table 1.  COMPARATIVE TOXICITY OF ORGANIC PHOSPHORUS
                    AND CHLORINATED HYDROCARBON INSECTICIDES TO
                                BLUEGILLS IN SOFT WATER
Organic
phosphorus
insecticide
Gluthion
Malathion
Parathion
TEPP
Methyl
Parathion
OMPA
9 6 -hour
TLm
(ppm)
0.0052
0.090
0.095
1.1

1.9
110
Chlorinated
hydrocarbon
insecticide
Endrin
Toxaphene
Dieldrin
DDT
Heptachlor
Lindane

96-hour
TLm
(ppm)
0.0006 f.fb
0.0035
0.0035
0.016
0.019
0.077

                  Note:  Above tests were run under standardized conditions
                     with soft water as a diluent at 25C.
                                                                                         32-3

-------
 Pollution Problem of Pesticides
    2  Chronic toxicity

       a  In recent years greater concern has
          arisen over the possible long term
          effects of the accumulation of small
          amounts of pesticides in the human
          body.

       b  Another aspect of this problem is
          the possibility of synergistic effects
          being  exerted as these pesticides
          accumulate.

    3  Taste and odor

       Pesticides and the solvents used in
       pesticide formulation can be highly
       odorous.
Ill  SOLUTION  TO THE PROBLEM

 A More research is needed in order to
    answer adequately the following questions:

    1  How general is the occurrence of
       pesticides in surface  and ground
       waters?  In order to answer this
       question, it is necessary that techniques
       of analysis be able to measure pesti-
       cides in water in the microgram and
       nanogramper liter ranges.  Pro-
       cedures being developed are according
       to the following general lines.

       a  Chlorinated hydrocarbons

          1)  Recovery of pesticides from
             water using the carbon filter or
             liquid-liquid extraction.

          2) Separation and identification of
             extracts.

             a)  Solubility and chromatographic
                separation serves as a clean-
                up procedure.  Pesticides are
                found in the aromatic fraction.

            b)  Thin layer chromatography
               serves both as a clean-up
               technique and as a means for
               confirmatory identification.
           c) Gas chromatography can be
              used for identification and
              quantitative assay of pesticides.

           d) Paper chromatography can
              also be  used for confirmatory
              identification.

        3) Infrared identification

           Absolute identifications of
           pesticides  can be made using
           micro infrared spectroscopy.
           However,  it is necessary to
           have recovered 1-10 micro-
           grams  of pesticide when using the
           Perkin Elmer Model 421 instru-
           ment with 6X beam condenser and
           a 1. 5 mm K Br disc.

     b  Organic phosphorus

        1) It is possible to measure  organic
           phosphorus compounds using
           electron capture gas
           chromatography.
        2)
However, the most popular
techniques developed so far have
been biochemical assays which
measure inhibition  of the enzyme
           measure inhibition
           cholinesterase.^ '
  2  What are the less obvious effects of
     pesticides on organisms in the aquatic
     environment?

  3  What factors relate to the presence
     or absence of pesticides in water?

  4  How well are pesticides removed in
     water treatment?

B  More Judicious Use of Pesticides

   As a result of the special  White House
   Report (May 14, 1963) and recent Senate
   hearings,  the Department of Agriculture
   has made  changes in some of its big spray
   projects.  Mirex, a compound with low
   toxicity to fish, was chosen to replace
   heptachlor in the Southeast fire ant
   program.  Sevin, also a compound with
   low toxicity to fish, was chosen to replace
   32-4

-------
                                                             Pollution Problem of Pesticides
    DDT to control the hemlock looper in
    Washington State.
IV  SUMMARY

 The  nature of pesticides in general is pre-
 sented and their potential as a water pollution
 problem is discussed.
  REFERENCES

  1  Breidenbach,  A. W.,  et al.  The Identi-
       faction and Measurement of Chlorinated
       Hydrocarbon Pesticides in Surface
       Waters.  PHS Publication # 1241.
       September 1964.

  2  Nicholson, H. Page.  Pesticide Pollution
       Studies in the Southeastern States. Pro-
       ceedings of the 3rd Seminar on Bio-
       logical Problems in Water Pollution.
       August 1962.
Pesticides in Soil and Water (an annotated
   bibliography). PHS Publication #999-
   WP-17.  September 1964.
Pickering, Q. H.,  et al.  Toxicity of
   Organic Phosphorus Insecticides to
   Different Species of Warm water
   Fishes.  Trans. Amer. Fisheries
   Society. 91:175-184.  April 1962.

Report on the Use of Pesticides.   Prepared
   by the President's Science Advisory
   Committee Panel on the Use of
   Pesticides.  May 14,  1963.

Weiss, C. M., and Gakstatter, J. H.
   Detection  of Pesticides in Water by
   Biochemical Assay. J. Water Pol. Control
   Fed. 36:240.   February 1964.
                                                                                        32-5

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           BASIC DATA FOR WATER SUPPLY AND WATER POLLUTION CONTROL

                                     Richard S. Green*
 I   AUTHORITY

 A  Public Law 410 (78th Congress)

 B  Presidential Advisory Committee on Water
    Resource Policy,  1955 - Recommended
    that the existing program of data collec-
    tion be accelerated, and carried out on a
    more consistent and definitive basis.

 C  Public Law 660 (84th Congress) -  Directs
    the Surgeon General, in cooperation with
    other Federal, State, and local agencies
    to collect and disseminate data on chemical,
    physical, and biological water  quality and
    other information insofar as such data re-
    late to water pollution control  and pre-
    vention.
II   NATIONAL INVENTORIES OF WATER
    SUPPLY, SEWAGE AND INDUSTRIAL
    WASTE FACILITIES
HI  FACILITIES CONSTRUCTION AND RE-
    LATED ECONOMIC INFORMATION

 A  Municipal Bond Data - Enables  program
    personnel to predict  probable levels  of
    future construction.

 B  Contract  Award Data - Shows how munici-
    pal funds are being spent for construction
    of water supply and sewage facilities.

 C  Construction "Put-in-Place"Data-Meas-
    ures actual progress of construction  of
    facilities.

 D  Financing,  Operation and Maintenance
    Costs,  and  Related Studies.

 E  Special Studies of Needs for New Facilities.
IV  WATER QUALITY DATA - WATER
    POLLUTION SURVEILLANCE SYSTEM
 A  Municipal Water Facilities

    All communities over 100 population -
    five year intervals

    Communities of 25,000 and over - biennial
 B Municipal Sewage Facilities

   All communities  over 100 population -
   five year intervals
 C Industrial Waste Facilities

   Five year intervals


 D Waste Water Disposal at Federal Instal-
   lations
 A  Objectives - to provide:

    1  Long term information on changes in
      water quality at key points in river
      systems as affected by changes in water
      use and development.

    2  Continuous information on the nature
      and extent of pollution affecting water
      quality.

    3  Data which will  guide State,  interstate,
      and other agencies in their water pol-
      lution control programs, and in the se-
      lection of sites  for legitimate water
      uses.

    4  Data on water quality useful in the de-
      velopment of comprehensive water
      resources programs.
E Data Processing and Publication of Inter-
   pretive Analyses
 *Chief, Basic Data Branch,  DWS&PC,  Washington, D. C.  Reviewed December 1965.

 W. 9a. 11.64                                                                           33-1

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Basic Data for Water Supply and Water Pollution Control
B  Sampling Stations Located on:

   1  Major waters used for public water
      supply, propagation of fish  and aquat-
      ic life and wildlife,  recreational  pur-
      poses,  and agricultural,  industrial,
      and other legitimate uses.

   2  Interstate,  coastal, and Great Lakes
      waters.

   3  Waters on which activities of the  Fed-
      eral Government have an impact includ-
      ing  (a) those where a pollution problem
      is substantially and adversely affected
      by a Federal installation, (b)  those
      waters needed for  national defense,
      and (c) those waters involved in a
      Federal water resource development.
C  Operations

   1  Size of System
      stations.
- presently 134
   2  State and local participation - perform
      established analyses and collect sam-
      ples for more complex analyses made
      in Cincinnati laboratories

   3  Compilation,  and publication of data -
      annual,  based on water year from
      October 1 to September 30.  Statistical
      and related studies.
D Laboratory Measurements Include:

   1  Long-established examinations - such
      as BOD, COD,  DO, pH,  color, turbi-
      dity, temperature, nitrates, chlorides,
      alkalinity, hardness,  etc.
                              2  Organic materials - using the carbon
                                 filter technique.

                              3  Coliform bacteria - using the delayed
                                 incubation, membrane filter technique.

                              4  Aquatic life - plankton, algae and
                                 bottom organisms.

                               5  Radioactivity  - gross alpha and beta,
                                 strontium-90.

                               6  Trace elements
E  Program Values - Provides:

   1  Ultimate measure of effectiveness of
      entire water quality control effort.

   2  Monitoring of significant changes in
      river basin water quality, providing an
      "alert", and suggesting possible
      control steps.

   3  Stimulation of laboratory activities at
      local level,  encouraging more com-
      prehensive coverage and utilization of
      water quality parameters needed to
      measure the effects of new pollutants.

      a  The Analytical Reference Service

   4  Encouragement and support for intra-
      State water quality networks.

   5  "Background" levels, required to as-
      sess degree of contamination resulting
      from the build-up of new pollutants.
                            V NATIONAL DATA ON POLLUTION-
                              CAUSED FISH KILLS
 33-2

-------
            OPERATIONS OF THE WATER POLLUTION SURVEILLANCE SYSTEM

                                     Robert C. Kroner*
I  ORGANIZATION OF THE WATER
   POLLUTION SURVEILLANCE SYSTEM
II   THE FUNCTIONS OF THE SERVICE
    LABORATORY ARE:
A  The System operation may be considered
   to be grouped into 4 separate activities,
   namely, the administrative operation,
   analytical activities, equipment and instru-
   ment development and data utilization.

B  Analytical activities are necessarily
   devoted to characterization of the samples
   and to operations which facilitate the
   accuracy of the data.  Five different
   disciplines are employed for qualifying
   and quantifying the samples:

   1  Biological examination for algae,
      diatoms,  other micro- and macro -
      plankton and eventually other forms
      such as benthos, fish, etc.

   2  Microbiological examination for coli-
      form and fecal streptococci organisms.

   3  Radioactivity assay for alpha and beta
      activities in the suspended and dis-
      solved fractions, strontium-90  and
      eventually other nuclides.

   4  Organic materials  characterization by
      means of the carbon adsorption method.

   5  Chemical analysis  for 16 conventional
      minerals,  spectrographic examination
      for 16 trace metals and other chemicals.
C  Each of the foregoing groups represents
   a different discipline and functions as an
   independent unit in the  System organiza-
   tion.  The biological, microbiological,
   organic and radiological groups examine
   samples taken especially for that particular
   analysis and obtain all  data related to the
   sample in the respective laboratory.  The
   chemical characterization, however,  is
   not necessarily done by the chemical
   analytical group,  which leads to the unique-
   ness of the Service laboratory.
 A  When an arrangement is made with a
    cooperating agency for participation in the
    Water Pollution Surveillance System program,
    the agency performs the conventional
    analyses as much as possible.  Sixteen
    mineral determinations are requested, as
    follows: Temperature, DO,  BOD, pH,
    COD,  Chlorine Demand (1 hour and 24
    hours), ammonia nitrogen, chloride,
    alkalinity, total hardness, color, turbidity,
    sulfate, phosphate and TDS.   Of these 16
    measurements, the  first  7 named must be
    performed by the cooperating laboratory,
    the remaining  9 measurements can be,
    and in many cases are, performed by the
    Service laboratory.

 B  The fact that the Service Laboratory must
    depend upon other personnel of varying
    skills  and backgrounds to supply data leads
    to activities not required by the other
    analytical groups in the System organiza-
    tion.   These activities are:

    1  Checking of field data for possible errors
      and inconsistencies.

    2  Completing analytical work not per-
      formed by field stations or repeating
      erroneous analyses.

    3  Performance of other analyses such as
      trace metals by spectrograph.

    4  Furnishing standard solutions, reagents,
      supplies, etc., to cooperating labora-
      tories.

    5  Conducting a standard sample program
      for cooperating laboratories.

    6  Conducting training courses for participa-
      ting agencies.

    7  Furnishing consultative services,  either
      personally or by mail.
*In Charge, General Laboratory Services, Water Pollution Surveillance System, SEC.
Reviewed December 1965.
W. LA. 3a. 6. 64
                                                                                      33-3

-------
 Water Pollution Surveillance System
HI  SPECIFIC ACTIVITIES OF THE SERVICE
    LABORATORY
 A As the number of cooperating agencies in
    the Water Pollution Surveillance System in-
    crease, the specific,  individual tasks in
    the Service Laboratory become more
    complex.   More field data forms are
    handled; characteristics of more stations
    require more familiarity; more supplies
    are required} personal consultation needs
    increase, etc. A brief elucidation of the
    more important of these  tasks  will be
    helpful.

    1  Checking of field forms.   Each coopera-
       ting agency reports a  weekly sample ,for
       conventional mineral analysis.  The data
       is supplied on the standard forms and
       each of the 100 forms is checked weekly
       for reporting errors.   Erroneous data
       is eliminated, questionable  data is
       checked by analysis whenever possible
       and unusual characteristics of the data
       are noted.

    2  Completing analytical work.  Approxi-
       mately 25% of the cooperating groups
       perform all the 16 required determina-
       tions.  This leaves a large volume of
       analytical work to be performed in the
       Service Laboratory and entails con-
       siderable bookkeeping on which labora-
       tory performs which determinations.

    3  Performs other analytical work.  A
       portion of each weekly sample is
       composited until a sufficient volume is
       obtained.   Supplementary analysis for
       sodium, potassium, fluoride,  seleni-
       um, boron and spectrographic examina-
       tion are completed  semi-annually.

    4  Standard samples.  To encourage co-
       operating groups to improve their
       techniques and to furnish a guide for
      reliability of data,  standard samples
      are supplied to each agency twice a
      year.  These samples are of two types,
      one requiring analysis for conventional
      minerals,  the other for the demand
      type of analyses such as DO,  BOD and
      COD.

      Training courses.  In order to increase
      the analytical skills of the participating
      personnel  and to furnish a fuller under-
      standing of the System program, train-
      ing courses are offered to the station
      personnel.  The courses at present are
      presented  semi-annually and consist
      of 3 -day sessions  devoted to various
      phases of the System operations.
B  The Service Laboratory and Contract
   Services.  An important phase of the
   Service Laboratory which results from the
   assembly of analytical facilities available
   in the Water Quality Section is the "con-
   tract service" operation.  The System
   characterizations cover a wide  range of
   analyses; and because  they are geared to
   mass production techniques, it is frequently
   more efficient for the System laboratories
   to perform analytical  work for a requesting
   organization than it is for the group to
   develop its own facilities.  This activity,
   which is performed on a reimbursable basis
   has continued to increase in volume until
   at present a large portion of the laboratory
   activities are devoted to reimbursable
   projects.

   It should be noted that these projects in-
   volve the organics,  planktonic and radio-
   logical facilities as well as the  chemicals,
   but that all contracts are handled through
   the Service Laboratory.  As a matter of
   fact, the term "Service Laboratory" is an
   outgrowth  of this particular service activity.
   33-4

-------
                                                                        Water Pollution Surveillance System
DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
               PUBLIC  HEALTH SERVICE
 DIVISION OF WATER SUPPLY AND POLLUTION CONTROL


      PROVISIONAL DATASUBJECT TO REVISION
                                                                                FOR WASHINGTON USE ONLY
                                                                              III)
                                                                              I     I	I     I
                                                                             l-Z   1-4   S-<   ?
                                                                                                       '
                                                                            CHECKED BY-

LABORATORY
                                                 T1IT MMH.TS
INSTRUCTIONS All boxes should contain  figure or preceding zeros.  U lotf M not
                           EXAMPLE  If D O is !O5 mg/l(ppm) enter *i foHows
                                    If TurMity ii SO units, enter *i foltews
                                                           mieV But "X'f" in eery box
                                                             1 i Q; 5]
1. TEMPERATURE
t. mmoLVEo
OXYGEN (00)

3. B-N
. BIOCHEMICAL OHYOEN DEMAND (BOD)
B.CM0M4CALC



. CHLORINE DEMAND - 1 HOUR
7. CHLORINE DEMAND . W HOUr*S
. AMMONIA NITROGEN 
                                                                         - *>
 IITf>l*UTIOt HtTm FIN* Cr>T IN fTICIfATIM LAMMTMY.  FD OKIalNAL IWMITtl AND M.UE COPY TO (ATEH 8UALITY

              HCTIB*. CIIICIMUTt. BNIB.
        i  NATrONAl WATM QOAUTY NETWOCK E*O*T (FID)
                                                                                   FORM t>moVED:
                                                                                   BUOOET BUREAU MO BB 
                                                                                                             33-5

-------
 Water Pollution Surveillance System
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33-6

-------
            AUTOMATIC INSTRUMENTS FOR WATER QUALITY MEASUREMENTS

                                     D. G. Ballinger*
 I   NEED FOR CONTINUOUS MONITORING
    OF WATER QUALITY

 Satisfactory evaluation of the quality of water
 depends upon the availability of adequate data.
 Such data must be not only  as accurate as
 economically practical but must also be of
 sufficient quantity to support reliable conclu-
 sions.  In general, the more information
 available,  the more reliable will be the
 interpretations.

 In the past, information on the chemical,
 physical, and bacteriological quality of most
 surface waters has been obtained by periodic
 stream surveys or infrequent  "spot" analyses.
 Although raw water supplies are sampled
 daily, the data obtained are  restricted to
 those tests  of importance in water treatment
 and do not include other pollutional parameters
 or water resources not at present  being used
 for water supply.

 It is apparent that in many situations signifi-
 cant changes  in water quality may  occur often
 and abruptly.  Seasonal changes in flow,  the
 occurrence of unpredictable industrial
 discharges  or spills,  and the changes in flow
 from impoundments may alter the  concentra-
 tion of many of the substances of interest to
 the water user.  In some cases these changes
 may occur within a few hours: for  example,
 the diurnal  fluctuations in dissolved oxygen
 and the salinity changes in tidal estuaries.
 Thus considerable advantage is gained if
 continuous monitoring of water quality can be
 accomplished.  The use of manual sampling
 and standard  laboratory analyses would be
 far too expensive; therefore a wide variety
 of automatic instruments have been developed.
II  ELECTRICAL INSTRUMENTS

 The diagram below illustrates a typical system
 for monitoring instruments which utilize
 electrical sensors.

 The sensor produces an electrical signal
 representative of concentration, the signal
ANALYZER

r




1


t

)
J





                 Figure 1
is converted, and amplified,  then passed to
the recorder to develop a permanent record
of concentration levels.  For a clear under-
standing of the operational characteristics,
the parts of the system are discussed
separately.
A  Sensors

   The sensor is the part of the system in
   contact with the sample.  Sensing
   elements may be immersed directly in
   the stream,  or placed in flow cells  through
   which the sample is pumped.  Both
   methods have advantages and limitations.

   When the sensor is placed in the stream
   the determination is made "in situ. "
   Therefore the sample is not affected by
   pumping, temperature changes,  or  time
   of travel through the instrument.  Such
   an installation, however, presents certain
   problems.  The sensing elements must
   be protected from floating debris and
   must be mounted so as to remain in a
   fixed position in spite of changes in velocity
   or direction of current.   In bodies of
   water which fluctuate  in surface level,
   such as impoundments, or estuaries, the
   relative depth of the sensor may change.
   In addition, frequent inspection of the
   sensing elements for attached growths or
   physical damage is difficult and apt  to be
   neglected.

   The use of the shore-based system,  where
   the stream sample is  pumped through flow
*Supervisory Chemist,  Technical Advisory & Investigations Section,  Technical Services Branch,
SEC.  Reviewed December 1965.
CH. MET. 18a. 9.65
                                     34-1

-------
Automatic Instruments for Water Quality Measurements
   cells within the instrument housing, is
   free from some of the difficulties mentioned
   above.  Inspection of the sensors is easy,
   cleaning is simplified,  and replacement of
   sensing elements is readily accomplished.
   It should be recognized,  however, that the
   precautions required for satisfactory
   mounting and protection of sensor units
   in the stream apply equally as well to the
   pump intake.  Further,  it is essential that
   the sample being  tested in the flow cell is
   truly representative of the stream water.
   If dissolved oxygen is included in the
   parameters, a submersible pump is
   required, to avoid cavitation and prevent
   suction removal of dissolved gases. The
   intake  screen must be carefully designed,
   since a fine screen will quickly  clog, while
   a coarse screen may permit floating
   material to enter the system.

   Electrical sensors may be conductimetric,
   potentiometric, polarographic,  or couli-
   metric.  The sensor may directly measure
   a constituent or property of the  sample or
   it may be used as an indicating mechanism
   in automatic titration.
B  Analyzer-Amplifier

   The function of the  analyzer is to convert
   the signal from the sensor to a standard
   EMF, usually ranging from 0-50 millivolts.
   Often bridge circuits are employed.  The
   analyzer must be rugged to avoid shock
   damage and the electronic  circuitry must
   be stable over a wide range of environ-
   mental conditions.  Considerable advantage
   is gained by the use of standard, readily
   available components.  Provision should be
   made for a standard signal to permit
   internal checking of the circuits.

   In most cases the signal must be amplified
   to provide sufficient voltage to drive a
   recorder.  Amplification is generally
   built into the analyzer circuitry.
C  Recorder

   Although read-out meters can be used, a
   permanent record is desirable. Stripchart
   recorders are the most popular even though
   they require line voltage.  A slow chart
   speed is necessary,  since observation
   periods of several days are common.
   Difficulties with pens are often encountered
   due to varying conditions of humidity and
   temperature.  The use of pressure-
   sensitive paper may offer distinct advantage.

   Circular charts have long been used but
   they have certain disadvantages. Unless
   the chart is inconveniently large the chart
   divisions are very close together making
   hourly fluctuations difficult to interpret.
   In addition, the circular chart does not
   lend itself to  mechanical handling of data
   for computer processing.  Chart drive by
   clock mechanism is possible, however,
   eliminating the need for power connection.

   A recent development in the recording of
   data is the use of digital output.  Water
   quality instruments can be equipped with
   analog-to-digital  converters which change
   the amplitude of the  signal to a digital
   value.  By the use of a punch-tape readout
   the data is recorded on paper tape rather
   than on a chart.   The punched tape may
   then be transferred to a computer for  data
   processing.   Therefore, a monitor equipped
   with digital tape readout permits the re-
   cording of original signal and the per-
   formance of statistical computations without
   hand transcription.

D  Parameters Measured Electrically

   The following water  quality parameters
   can be measured  by  the use of electrodes:
   Temperature
   Conductivity

   pH


   Oxygen
Chloride

Residual chlorine

Oxidation-reduc-
tion potential
   A prominent instrument manufacturer is
   now conducting research into the develop-
   ment of a number of glass electrodes
   specifically designed for the measurement
   of other ions.  It appears that the list  above
   may be considerably expanded in the future.
 34-2

-------
                                       Automatic Instruments for Water Quality Measurements
    In most cases precision and accuracy is
    not as good as with standard laboratory
    tests,  but the advantages  of continuous
    recording outweigh the limitations in
    performance.

HI  PHOTOMETRIC INSTRUMENTS

  Because of the importance of colorimetric
  analysis in the water laboratory,  considerable
  attention has been given to the development of
  continuous monitoring instruments employing
  this principle.  A typical system is shown
  in Figure 2.

  It should be noted that the sample must be
  pumped through the instrument with the
  attendant problems described above.

  A Measurement of Turbidity and Color
                  /
    In the simplest photometric instrument,
    a property of the sample, such as turbi-
    dity or color, is measured directly.  These
    relatively simple parameters,  however,
    are rather difficult to determine.  Turbi-
    dity measurements are  affected by particle
    size and by the true color of the sample.
    Conversely,  color determinations are
    subject to errors caused by turbidity  and
    by the  fact that  the wavelength  of the color
    in the sample may vary widely. Instruments
   of this type currently available do not
   satisfactorily compensate for these
   interferences and the data obtained from
   them does not correlate well with standard
   methods values.

B  Colorimetric Analyzers

   A second type of photometric instrument
   is designed to reproduce laboratory
   colorimetric procedures. That is, re-
   agents are added to the sample to produce
   a color change proportional  to the con-
   centration of the material being determined.
   Since the sample is flowing continuously
   the reagents must be metered accurately
   and mixed thoroughly before photometric
   measurement.  In a properly designed
   system, almost  any colorimetric procedure
   can be duplicated and therefore the potential
   range of determinations is much  wider than
   than in the electrometric instruments.

   A modification of the colorimetric instru-
   ment is the continuous titrator.   In this
   system an indicator is added to the flowing
   sample and the  reagent is added at  a vari-
   able rate to maintain a constant color.
   The amount of reagent required is pro-
   portional to the concentration of the re-
   actant in  the sample,  and the current used
   by the metering pump acts as a signal for
   the analyzer.
                                                ANALYZER
                                                                        RECORDER
                                                COLORIMETER
           SAMPLE
 DRAIN
                                           Figure 2
                                                                                       34-3

-------
Automatic Instruments for Water Quality Measurements
   In spite of the apparent advantages of the
   photometric systems, certain special
   problems are inherent.  The color and
   turbidity of the sample may interfere, the
   accumulation of slime in the cells may
   seriously reduce the sensitivity,  and the
   limitations of the filter photometer (wide
   band pass) must be considered.  Further,
   in most colorimetric procedures  the
   amount of reagent  required is proportional
   to the concentration range of the sample,
   a factor which would limit the applicability
   of the instrument.

C  Parameters Measured Photometrically

   Continuous analytical procedures have
   been developed for:
                         Fluoride

                         Silica
                         Phosphate
                         Phenols
                         Chemical Oxygen
                         Demand
    Turbidity

    Color
    Hardness

    Residual Chlorine
    Alkalinity



IV  PERFORMANCE
To illustrate the quality of the data which may
be obtained from an integrated water quality
monitor, the table below shows the results
of a performance test conducted on a proto-
type instrument supplied by one manufacturer.
The "Acceptable" tolerances were selected as
representative of the usual requirements for
continuous data acquisition and may be too
high or too low, depending upon the  accuracy
deemed necessary.
V  CALIBRATION AND MAINTENANCE

A  Calibration

   In the parlance of the instrument manu-
   facturer,  calibration involves two steps:
   (1) the setting of the readout to zero value
   in the absence of sensor signal, and
   (2) setting of the readout to some standard
   value,  such as 5mv. when the sensor
   signal is replaced by a standard signal.
   It is readily apparent that a calibration
   of this type adjusts  the meter  and amplifier
   to reproduce correctly the signal received
   from the sensing elements.  It does not,
   however,  "calibrate" the total instrument
   in terms of the concentration  of measured
   substance in the sample.

   For  proper calibration,  it is essential
   that  the final readout of the instrument be
   adjusted to correspond to a true value for
   the  measured material.  Thus the only
   adequate calibration must involve the
   measurement of a standard solution,  such
   as a buffer of known pH or a salt solution
   of known conductance.  Since  instrument
   systems may lack linear response to a
   wide signal range,  the instrument should
   be calibrated at several points over the
   range of values anticipated.  In some
   cases current instrument design has not
   included adequate means of replacing the
   sample with  standard solutions for calibra-
   tion purposes.

   The  frequency of recalibration depends
   upon both the stability of the analyzer and
   the  sensor.   In general, analyzer-
   amplifiers are more stable than the sensing
   systems now in use.  The PHS National
           Test

     PH

     Temperature

     Conductance

     Dissolved Oxygen
                                    PERFORMANCE DATA

                            Acceptable deviation      Mean deviation found

                                 + 0.1 unit
                                 + 1
                                   0.5mg/l
0.1 unit

0. 2



0.3 mg/1
                           % Acceptable

                                80%

                                85%

                                99%

                                73%
    34-4

-------
                                       Automatic Instruments for \\ater Quality Measurements
   Water Quality Network, in performance
   specifications for monitoring instruments,
   has established a two-week period for un-
   attended performance.  While such instru-
   ment stability is desirable, under certain
   circumstances, site location and sample
   characteristics, may necessitate more
   frequent checking and recalibration.

B  Maintenance

   It is unwise to assume that any stream
   monitoring instrument,  no matter how
   well designed and built, can function
   adequately for extended periods of time
   without maintenance. Sensing elements
   are subject to physical, chemical, and
   biological actions, analyzer components
   may fail or perform erratically,  and
   recorders may stop  or fail to print.   The
   frequency of maintenance depends upon a
   large number of factors both controllable
   and accidental and can only be determined
   by long-term testing and actual field
   experience.  Ease of maintenance can be
   designed into the instrument by the use of
   replaceable electronic components and
   accessibility  for cleaning of flow cells
   and sample lines.

   The availability of trained personnel for
   checking and  maintaining  the instruments
    in the field is a key factor in the success-
    ful stream monitoring program.  Such
    personnel  need not be either electronic
    specialists or  experienced analysts but
    they should have a working knowledge of
    the instrument system  and a familiarity
    with the chemical principles involved in
    the use of standard solutions  for
    calibration.
VI  APPLICATIONS

  Stream monitoring systems are now in use
  in a variety of locations throughout the
  United States.   In most cases the instruments
  measure a single parameter or condition of
  the stream rather than a number of para-
  meters.  Some of the instruments employ
  well established measurement systems,  for
  example pH and conductance, while others,
  such as DO and the colorimetric procedures,
  are  still largely experimental.

  Because of the need for continuous stream
  data, the intensive interest on the part of
  regulatory agencies, and the development
  programs by instrument makers,  it  is safe
  to assume that the use of water quality moni-
  toring instruments will increase significantly
  in the near future.
                                                                                       34-5

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        MATHEMATICAL BASIS OF THE BIOCHEMICAL OXYGEN DEMAND (BOD) TEST

                                       D. G. Ballinger*
 I   FUNDAMENTAL CONCEPTS

 Since the early 1900's, the oxidation of
 organic waste substances in natural waters
 has been under investigation.  Certain
 fundamentals are now universally accepted.
 These are:

 A  Dissolved oxygen in the water is reduced
    during stabilization of the organic  material.

 B  As long as there is dissolved oxygen pre-
    sent, the rate of oxidation is independent
    of the  actual amount of oxygen available.

 C  The type  and numbers of biological forms
    present is an important factor.

 D  Measurement of changes in oxygen content
    can  be related to quantity and character
    of oxidizable organic matter.
II   FIRST ORDER RATE CONCEPT

 In order to illustrate the mathematical
 relationships in the BOD reaction, assume
 the following laboratory observations:
                     A  A set of replicate bottles is filled with
                        river water and sealed so that outside
                        air is excluded.

                     B  Each day, one of the bottles is analyzed
                        for DO content,  and the results tabulated.
                        (See Table 1.)

                        It will be noted that on each successive
                        day, the DO concentration is less than
                        the day before.  That is, oxygen  is being
                        consumed by biological action in  the
                        water. If the results of the DO test are
                        plotted against time, a curve, as in
                        Figure 1  will be produced.

                        The cumulative oxygen removed from the
                        sample, (the oxygen demand) when plotted
                        against time, yields an inverted image
                        of  Figure  1.  If the oxygen demand per
                        day is drawn in, it is apparent that an
                        increasingly smaller amount of oxygen  is
                        required  each successive day, Figure 2.
                        Note also,  a constant percentage of the
                        oxidizable material present at the begin-
                        ning of each day is oxidized.  Therefore
                        "K" - the  reaction rate coefficient - is
                        constant from day  to day,  although it may
                                           Table 1.
         Days
DO
       Oxygen depletion
Per day                Cumulative
0
1
2
3
4
5
6
7
8
9
10
9.2
7.4
5. 8
4. 6
3. 7
2. 9
2. 3
1. 8
1. 5
1. 2
0. 9
0
1.8
1. 6
1. 2
0. 9
0.8
0. 6
0. 5
0. 3
0. 3
0. 3
_
1.8
3.4
4,6
5.5
6.3
6.9
7.4
7. 7
8.0
8. 3
 ^Supervisory Chemist, Technical Advisory & Investigations Section, DWS&PC, SEC.
 CH. O.bod. 49b. 12. 65
                                                          35-1

-------
     Mathematical Basis of the BOD Test
 yv;
/
  vary in magnitude from sample to sample,
  and with temperature changes.

  Similarly, the organic matter present in
  the sample is being oxidized,  so there is
  progressively less oxidizable material
  present each successive day.  The
  relationship between oxygen demand and
^amount of oxidizable material present
  can be stated as follows:  The oxygen
  demand per unit time is proportional to
  the amount of unoxidized material present.
  Streeter and Phelps^  ' stated the concept
  as - the rate of biochemical oxidation of
  organic matter is proportional to the con-
  centration of unoxidized substance,
  measured in terms of oxidizability.  The
  same  authors also stated that there is no
  logical reason to expect one rate constant
  but it may appear  so because of crude
  measurement and  the effects of many
  individual oxidation systems.  Such a
  rate is termed a First Order Reaction
  Rate.

  The curve as shown in Figure 2 is the
  typical BOD curve.  When interpreted in
  light of the fundamentals previously dis-
  cussed,  it is apparent that:

  1   With organic  materials which are
     easily oxidized, the reaction proceeds
     rapidly, nearing complete oxidation
     in a few days.  The curve is therefore
     steep, rapidly approaching a maximum.
     The slope of the BOD curve is therefore
     a function of the rate of oxidation.
                                                         2  As oxidation nears completion,  the
                                                            curve approaches some maximum
                                                            BOD value.  This value represents
                                                            the total oxidizability of the organic
                                                            matter in the sample.  It is termed
                                                            the ultimate demand.
Ill  BOD EQUATION

 Using the typical BOD reaction curve, it is
 possible to develop equations expressing
 the various relationships.  Labeling the
 coordinates as in Figure 3.

       t  =  time in days
       L  =  ultimate demand
       L^. =  demand remaining at time t
       y  =  demand satisfied at time t
                                                         then:
                                                            L  =  y + Lt total demand is equal to
                                                                  BOD oxidized plus BOD remaining
                                                               =  fraction of L remaining at time t
                                                            I  -
                                                            L
          =  fraction of L oxidized at time t
                                                         and
                                                                  t     v
                                                            1 -  =   f- =  fraction oxidized
                                                                 L-i      Lj
     35-2

-------
                                                      Mathematical Basis of the BOD Test
The relationships may be expressed as a
differential equation with respect to "t"
            -dL
            dt
            =  KL
                               (1)
   where K is a constant.

   Integrating equation (1):
           TIME IN DAYS



         Lt
      Ln_E  = -Kt            (2)


changing to common logarithms:

           L,
                  t
                     ~~ -kt
                               (3)
      and:
            Lt
      since    = fraction remaining
            L

              -kt
      then:  10    = fraction remaining

                   Lt
      and since  1 -  = fraction oxidized
then:  1 - 10"kt
          L
and:  1 -  ^ =  1 - 10"kt
          L
                     = fraction oxidized

                      - 10"kt        (4)
                                                  multiplying both sides of equation (4)
                                                  by L:
                                                                            -kt'
   L - Lt = L (1 - 10

since:  L - L, = y

then:  y = L (1 - 10"kt)
                                                                         ;)
                                                                                  (5)
                                                        This is the usual form of the BOD
                                                        equation.  To avoid confusion with
                                                        other "k" values,  the constant is  usually
                                                        written as k-^  and the equation  becomes
                                                                = L (1 - 10~klt)
                                                        where:
                                                           y = the biochemical oxygen demand
                                                              at time t,  as measured in the
                                                              laboratory.

                                                           L = the ultimate demand,  when
                                                              oxidation is complete.

                                                           kj= the logarithmic rate constant.

                                                           t = any time interval after oxidation
                                                              has begun.

                                                        Thus  (y) the demand which has been
                                                        satisfied at time  (t), is dependent upon
                                                        the ultimate demand of the organic
                                                        material (L),  the rate at which
                                                        oxidation  is taking place (k-j)  and the
                                                        elapsed time (t).
                                           IV  SIGNIFICANCE OF BOD CONSTANTS

                                            kj:The rate is dependent on many factors
                                               such as  temperature, nutrients, biological
                                               population, etc.  These will be discussed
                                               extensively in another section.  Mathemati-
                                               cally,  k} is the slope of the BOD curve.
                                               Its effect upon y is shown in Figure 4.

                                               The upper curve represents the BOD of
                                               domestic sewage.  The  kj rate is  0. 15.
                                               At this rate,  50% of the demand will be
                                               exerted  in the first two  days,  indicating
                                               that the  organic matter  is readily  avail-
                                               able as food for the organisms.  In five
                                               days,  83% of  the demand has been satisfied
                                               and in 15 days,  the oxidation is essentially
                                               complete.
                                                                                        35-3

-------
Mathematical Basis of the BOD Test
   The lower curve represents the BOD of
   an unpolluted stream.  The k-^ rate in this
   case is 0. 05.  Since the organic matter
   present is essentially stable,  further
   oxidation proceeds slowly.  In five days,
   only 44% of the demand is  satisfied and
   at 15 days, there is still 17%  of the
   material unoxidized.  Note that at the
   slower rate,  it takes 15 days  to accomplish
   83% oxidation, while at the faster rate,
   the same percentage can be accomplished
   in 5 days.
          EFFECT OF K RATE ON SHORT TERM B.OJD.
   Laboratory tests on the BOD of waste
   materials are generally 5 day tests.
   In the case of these  two samples, the
   standard 5 day interval would represent
   vastly different degrees of oxidation.
   Thus it is apparent that 5 day BOD values,
   without supplementary knowledge of the
   rate of oxidation, are of little practical
   value.

L: The ultimate demand L is generally re-
   garded as a theoretical limit rather than
   an actual one.  The  conditions which
   govern the oxidation reaction are seldom
   stable for the extended periods  required
   to complete oxidation.  L values are
   useful, however, for predicting the
   ultimate demand  on  the oxygen resources
   of the stream.  It is the total demand that
   is important,  not just the demand at a
   particular  time interval.

   Further, since the total demand is
   independent of the rate  of oxidation,
    waste comparisons in terms of L values
    are much more significant than comparison
    of 5 day BOD values.

    Both K and L are approximations useful
    for engineering estimates.  They are not
    "constants".  K tends to become smaller
    as  the more rapidly oxidizing components
    of a mixture are exhausted.  As K
    diminishes the estimate of L increases
    for a given y,.


V   LOG OF %  BOD REMAINING

 Using the mathematical relationships
 established above, a second BOD equation
 can be developed.  This equation is useful
 when tables of logarithms are available.


    since:    =10   1  = fraction remaining
    10~klt X  100 = % remaining

    Iog10 (10~klt X 100) = Iog10% remaining
    further:
       logjQdO'kl*  X  100) = 2 - kjt

    then:

       log of % BOD remaining =  2 - k1t
 By the use of this equation, the handling of
 exponential values is simplified.

 The equations herein developed express the
 relationships of the various factors in the
 BOD reaction.  Since a precise mathematical
 arrangement can be  shown, the existing
 waste problem can be evaluated in terms of
 the present oxygen demand, the rate of
 stabilization,  and the ultimate demand on the
 oxygen resources.
 REFERENCES

 1  Streeter, H.  W., and Phelps, E.  B.
       Public Health Bulletin 46, USPHS.   1925.

 2  Phelps, E. B.  Stream Sanitation.  John
       Wiley & Sons, New York.  1944.
35-4

-------
                                  ESTIMATION OF K AND L
                                       F. J. Ludzack*
I  Several methods are available that may
give a fair estimate of K and L providing
that the observed data plots in a  form that
suggests a first order reaction rate fit.
The fact that stream samples frequently
consist of partially stabilized river water
mixed with varying amounts of more recent
wastewater additions leads to numerous
situations where observed data calculated
as "a" first order reaction does  not give a
good fit of observed and calculated data.
The low rate oxidation of the aged material
and high rate oxidation of the  new material
simply cannot be explained in terms of one
K and L.

The BOD test is not precise enough to
distinguish the infinite number of individual
rate systems included in deoxygenation of
a mixed wastewater by the mixed organisms
involved.  The persistence of the first order
reaction rate concept (incorrectly called a
monomolecular rate) partially is due to the
practical limitations  of the test.   High
assimilative oxidation rates (Figure 1)
generally have been partially  completed
in the sewer,  during compositing or sample
storage before BOD analysis, or in the
receiving water. Remaining deoxygenation
takes the form characteristic of  cell mass
and storage products, (endogenous oxidation)
which for a few days  shows a  k^  of about 0.1.
If the observation period was  extended beyond
the usual 7 to 10 days for rate estimation a
progressive lowering of k^ would become
apparent as the more oxidizable  components
disappeared and relatively inert  biological
or other residues became a larger and
larger fraction of the total oxidizable mass.
 mathematics as a tool rather than as a deity,
 will produce useful estimates for resolution
 of the problem.
II  Useful methods of deriving K in natural
 log or the more commonly used rate term
 for deoxygenation, k^ in Iog10 include the
 least squares method of Reed and Theriault
 (Public Health Bulletin  127, 1927); the
 Thomas Slope  Method (Sew. Works J. 9,
 No.  3,  425,  1937) as modified by Ettinger,
 the Moments Method of  Moore, Thomas, and
 Snow (Sew. and Ind.  Wastes 22, No. 10, 1343,
 1950) and the Rapid Ratio Method of Sheehy
 (JWPCF 32,  No.  6,  646,  1960).  The first
 three of these presume  a  single rate factor
 and do not give a  good fit  of data when
 deoxygenation fails to follow the pattern.
 Certain other factors in calculation mechanics
 enter the picture  even when the curve appar-
 ently follows first order characteristics
 (Ludzack et  al, Sew. and  Ind.  Wastes 25,
 No.  8,  875,  1953).  Sheehy's procedure
 elucidates the disappearance of high rate
 components  during early stages and can be
 very useful for rapid calculations.

 The daily difference  method outlined by
 Tsivoglou (Oxygen Relations in Streams,
 SEC Tech. Report W-58-2,  p.  151, 1958)
 is an adaptation of Velz' technique and gives
 a graphic picture of observed data and pre-
 dominant rate  changes with time.  The method
 is rapid,  versatile, and gives a great deal
 of information in  a simple package that is
 readily assembled.

 A For example with given observed BOD's:
   Time interval
Thus the computed k^ and L are a result of
the selected measurement routine, past
history of the sample, and the manner of
processing the result. The validity of the
estimate depends upon engineering judgment
and a realization of the variables and effects
involved. No two individuals will derive
precisely the same values from given data
but common sense approaches using

days

0
1
2
3
4
5
6
7
(mg/1)

0
0.
1.
1.
1.
2.
2.
2.


72
20
55
82
02
20
37
Difference


0
1
2
3
4
5
6


to
to
to
to
to
to
to


1.
2,
3,
4,
5,
6,
7,


0.
0.
0.
0.
0.
0.
0.


72
48
35
27
20
18
17
*Chemist,  Chemistry and Physics,  Basic and Applied Sciences Branch,  DWS&PC, SEC.
CH.O. bod. 55. 12. 65
                                    35-5

-------
Estimation of K and L
           SIMULATED HIGH AND LOW RATE
            OXIDATION CURVES AND THEIR
                 INTEGRAL EFFECTS
        INCREMENTAL
         ADO/AT
       ASSIMILATION PHASE
                ^=.
                      ^^H^V * ^^^^
                  ^^^**  ^^^^
                        S ADO vs. Time,
                            Scale x 1/3
                     INTEGRAL OR COMPOSITE CURVE
                          INCREMENTAL	
                            ADO/AT
                          ENDOGENOUS PHASE
 6     8     10
OBSERVATION TIME

     Figure 1
                                 12    14
35-6

-------
                                                                    Estimation of K and L
1  Plot y vs t on coordinate paper.  Draw
   a curve of best fit through the observed
   points,  including lags, plateaus, if any,
   to get a picture of the deoxygenation
   curve.  Wild values then can be
   eliminated by using the curve values  in
   subsequent calculations.  Lags should
   be eliminated by  curve fitting and taking
   the observed points after the lag
   termination.

2  Plot the daily differences,  corrected
   if necessary,  on  semilog paper  with
   time on the linear scale and the daily
   difference on the log scale.  The
   differences are conventionally plotted
   as 1/2,  1-1/2, 2-1/2 days, etc.
   (Figure 2).

   From the plot it is apparent that the
   rate changes between the fourth and
   fifth day.  For calculation  of the high
   rate system assume that it is no longer
   dominant after the fourth day.

3  From 0 and 4 day intercepts  of the

   line of best fit  ^ or the fraction
                        23
   remaining becomes -~^- = 0. 28.  The
   fraction oxidized =  1 - -    = (1-28)=. 72
                         L
4  k^ may be estimated from the
   Theriault tables where t = 4 and
   ( 1 -  10"kt) = . 72

   where k^ = 0. 14 becomes the nearest
              value.

   a  Alternately k^ may be estimated
      from the  relation Log of % BOD
      remaining = 2 - k^t

      where % BOD remaining is 28 and
      t = 4

      Log 28 =  1. 45
      or 1.45 = 2 - ki(4)

      kl=  ^  =0.14

5  L may be estimated from the Theriault
   tables using the relation y^
       and known values for yt for 4 days of
       1. 82 and (l-10~kt) of . 72

       or 1. 82 = L (.72)
Ill  From Figure 2 it is clear that the k^ of
 0. 14 and L of 2. 5 are subject to the influence
 of the lower rate oxidation which is dominant
 after the fifth day, but apparently was active
 from the initial day.  Extending the low rate
 line to the initial day provides a means to
 estimate the relative contributions of each
 rate group.

 A The log difference  of the  corrected
    hi-rate group for 0 to 1 day now becomes
    . 72 - . 22 = . 50.  Subsequent differences
    are .27, .15 and .07.

 B A new  rate estimate corrected for the low
    rate system provides a line (Figure 2)
    with the 0  intercept at 0.  72 and four day
    intercept at 0. 05.
C  The % BOD remaining
            0  05
   becomes   -   X 100 = 7.
                               = (lO"kt)
                                 V    /
    where Log % remaining = 2 - k^t

       for four days 0. 85 = 2 - k1(4),  or
             1. 15
       kl =
                = 0.29
    where yt = L (l-10"kt)

       for four days y^. =  1. 82,
       (1-10-kt) = (i. 0-0.07) = . 93

       L =-:gg- = 1. 96 or 2.0


 D The  corrected high rate group calculations
    now show that:

    1  93% of the ultimate rapid rate demand
       was exerted in four days.

    2  The estimate of L was 2. 5, uncorrected,
       and 2. 0,  corrected,  therefore about 80%
       of the observed four day demand was due
       to the hi-rate group.
                                                                                     35-7

-------
Estimation of K and L
DAILY DIFFERENCE ADO/AT
V- N u> :t cn   -^ ootoo o o o o o o o <

St.
vs
\i ^
i \
,,_ | 
1
1

-
-
-
-




\
I x
1
\[
%
-ix










t^ADO
V
V
i
i
i
\








I/AT Ci


ADC
F
\
\
\





)MPO<
ATESJ


I/AT C
1IGHEF


V






SITE

yLOW
* f^. W% i
ORREi
\ RATE











RATE
OUP
;TED
:GROI
-
-i
-
-
-
IP
                                    DAYS
                                    Figure 2

-------
Estimation of K and L
Theriault Table
NUMERICAL VALUES OF THE FUNCTION (1 -
FOR THE RANGE k = 0.040 to k = 0. 250
Period of
incubation
(days)
1__ . __
2-..-....
0 	 ..

4 -._--. -
5 ____-._..-
6 -__.._.._-
7_-__-.-__
8_

9-^---.---

1 9--. _--__-


H ---_-._.
1 ^--_-----
1 A-. ______
1 7--_--__-
1 fl---_-__-


91 _-._--__-
99-.. __--__
9^--_--_-_
9A--------
9R_____-__

Period of
incubation
(days)

2 ______.._
}--_..____
4  _ 	

0.04
0.088
.168
.241
.308
.369
.425
.475
.521
.563
.602
.637
.669
.698
.725
.749
.771
.791
.809
.826
.842
.855
.868
.880
.890
.900

0.11
0.224
.397
.532
fi37

0.05
0.109
0.206
0.292
.369
.438
.499
.553
.602
.645
.684
.718
.749
.776
.800
.822
.842
.859
.874
.888
.900
.911
.921
.929
.937
.944

0.12
0.241
.425
.563
fifiQ

0.06
0.129
.241
.339
.425
.499
.563
.620
.669
.712
.749
.781
.809
.834
.855
.874
.890
.905
.917
.928
.937
.945
.952
.958
.964
.968

0.13
0.259
.450
.593
RPQ
Value of k
0.07
0.149
.276
.383
.475
.553
.620
.676
.725
.766
.800
.830
.855
.877
.895
.911
.924
.935
.945
.953
.960
.966
.971
.975
.979
.982
Value of k
0.14
0.276
.475
.620
72Fi

0.08
0.168
.308
.425
.521
.602
.669
.725
.771
.809
.842
.868
.890
.909
.924
.937
.948
.956
.964
.970
.975
.979
.983
.986
.988
.990

0.15
0.292
.499
.645
74Q
. 10 -kt)

0.09
0.187
.339
.463
.563
.645
.712
.766
.809
.845
.874
.898
.917
.932
.946
.955
.964
.970
.976
.981
.984
.987
.990
.991
.993
.994

0.16
0.308
.521
.669
771


0.10
0.206
.369
.499
.602
.684
.749
.800
.842
.874
.900
.921
.937
.950
.960
.968
.975
.980
.984
.987
.990
.992
.994
.995
.996
.997

0.17
0.324
.543
.691
7Q1
                 35-9

-------
Estimation of K and I,

Period of
(days)
K 	

6 ....-. __
8 ____.. 	

9 _-__-..-__
1 f)--- 	

n_ 	 	 	
1 o_ 	 .._ 	
1 ^--_ 	 	 	

U-_ -
1 C _ _ __
1 fi-_-__-__
i 7__,. 	 _
1 R-___.--.
1 Q~___ ___

^U

Period of
(days)
i .--._-.-__

3_
4_ 	 ___
5 ____--_

6_ 	 	
7--,.- 	

8_ 	 	
9__. 	 ._
1 0--------

1 9-.-- 	 --
1 ^__------
1 4__------




0.11
71 fl
7pi
por
ftfift
PQp
Q91
QOp
QC n
QfJO
Q7 1
. y 1 1
Ql?p
 y i o
QP7
QQA
QQO

 yy^t


0.18
0 339




Q1 7


Q7R
QDA
QQA


QQ7
QQQ



0.12
7AQ
pAQ
pCC
QH
Q 1 7

QC O
Qfi A
07 o
Q7Q

QQQ
QQ1
QQQ

QQR



0.19
0 354

70.1

QQQ


Q7n
QP.1
QR7
QQ9

QQ7
QQp
QQQ

Theriault Table
Value of k
0.13 0. 14 0.15 0. 16



QAQ Q9J. Q77 QAft



Q79 Q7Q QQA QQQ


.985 .989 .992 .994
QQ9 QQA *.



QQ7 QQQ


Value of k
0.20 0.21 0.22 0.23 0.24
0 369 0 383 0 397 0 411 0 425
602 620 637 653 669
749 766 781 7Q6 809
842 855 868 880 890
900 911 921 929 937

Qfif) Pfifi Q71 97S P79
Q7^ Q7Q Qft? Qflfi QRfl
Q84. QR7 QQfl QQ1 QQ1^
QQO QQP QQ4- QQ.*, QQfi
QQ4. QQ1^ __._ ....-. -_--
QQR 007 	 	 	 	
QQ7 QQfi 	 -_- - 	
QQO QQQ 	 	 	 	
QQQ QQQ - _-   . __..



0.17

QAC
Q ^c^
QRfi
Q7H
Qpn
Q P7
QQ 1
. yyi

. yyo
.997




"" "* 


0.25
0 438
684
822
900
944
Qfift
QP9
QQO
QQA
QQ7






35-10

-------
                                                  Estimation of K and L
   Similar calculations for the corrected
   low rate group show a k^ of 0. 01 and
   L of 7. 6 based on the zero to seven
   day extrapolated curve of the low rate
group.  The zero and seven day
intercepts show BOD remaining of
. 18
. 22
   = . 82 or 82%.
O
z
LU
ee
o
CO

I-
z
UJ
o
cc.
UJ
0.
      100


      80
      60
      40
      30
      20
       10
             RATES  OF  B.O.D.  SATISFACTION

                FOR VALUES  OF  K,  FROM .05 TO.60
                                               14    16    18   20
                             TIME  IN  DAYS
                                                               35-11

-------
  Estimation of K and T,
IV  The seven daj  observation period gives         ,>->plitting in a sludge deposit may produce
  enough data to show the basi< characteristics      cleavage products showing  deoxygenation
  of the system.  The derived values are            rates much greater than 0.01.
  relatively crude values based upon specified
  conditions and it cannot be assumed that the        Derived figures are useful  engineering
  stream approaches or will maintain those1          estimates for a given system, conditions, and
  conditions.   For example, the hydrolytic          time.  They are not absolute or constant  values.
  35-12

-------
                     ATOMIC ABSORPTION SPECTROPHOTOMETRY

                                    Nathan C. Malof*
 I  INTRODUCTION

 Atomic absorption is a relatively new method
 for determining the presence and amount of
 an element in a laboratory sample.  In 1953,
 Walsh(i) in Australia,  recognized its potential
 advantage over emission spectroscopy for the
 analysis of routine samples. Previously the
 method had been used in a restricted way for
 analyzing mercury vapor in the atmosphere
 and terrestial samples. Walsh devised
 apparatus sufficiently simple, versatile and
 inexpensive to be applicable to routine analysis
 of solutions containing a wide range of elements.
 It was not until 1960 that the advantages of
 atomic absorption were recognized in the
 United States.
II  THEORY

 If sufficient energy is added to an atom some
 of the electrons will move from the normal
                       or ground state orbital to an orbital of higher
                       energy or an excited state.  Since the higher
                       energy level is unstable, the electron will
                       return to its original ground state.  The re-
                       turn to ground state is accompanied by the
                       release of radiant energy and this energy can
                       then be measured.   This is  the principle of
                       emission spectroscopy.  The radiant energy
                       produces a spectral line of  characteristic
                       wavelength and frequency for a particular
                       element.  An electron will absorb energy
                       at the same characteristic wavelength at which
                       it emits energy. This is the basis for atomic
                       absorption spectroscopy.

                       In atomic absorption, light  from a cathode
                       made of the element being measured is passed
                       through a sample which is vaporized by a
                       flame.  The ground state atoms in the flame
                       absorb the  light, diminishing its intensity.
                       The percent absorption noted by the detector
                       is then a measure of the concentration of the
                       element in the sample.
 HOLLOW-CATHODE
        LAMP
          VAPORIZING
ROTATING SYSTEM
 CHOPPER     v FLAME
                      | SLIT
                                                    MONOCHROMATOR
                     SAMPLE  IN   FUEL IN
                                                                            PHOTO-
                                                                          DETECTOR
                              ELECTRONICS
                                    AND
                                 READOUT
                                        Figure 1
*Chemist, Technical Advisory & Investigations Section, DWSPC,  SEC.

CH. MET. aa. 1. 12.65                                                               36-1

-------
 Atomic Absorption Spectrophotometry
               RESONANT
               AMPLITUDE A
I <*> ABSORPTION

f
X  ABSORPTION
4

u
                       A
                 B
                  ll-XI A
                                               100
                                                                    D
                                          (l-XI A
                                               E

                                           Figure 2
III  INSTRUMENTATION

 There are four basic parts to an atomic ab-
 sorption spectrophotometer; the light source,
 a means of vaporizing the sample,  a system
 for isolation of resonance line,  and the
 detector.

 A  Light Source

    For the more volatile elements  such as the
    alkali metals, mercury and thallium, the
    most  convenient source is the spectral vapor
    lamp.
   For line sources of the less-volatile
   elements, hollow-cathode discharge tubes
   have been found most satisfactory.

B  Vaporization of Sample

   1  Atomic-absorption methods have been
      applied amost exclusively to the  analysis
      of solutions.  For this  purpose flames
      similar to those used in flame photo-
      metry are used.

      Several different gas mixtures have
      been used such  as those shown in Table 1
 36-2

-------
                                                     Atomic Absorption Spectrophotometry
      but for most routine work an air-acety-
      lene has been found to be superior to
      other mixtures if both convenience and
      sensitivity are considered.  However,
      Al  Be, Ti and V, because of the re-
      fractory nature of their oxides, prevent
      production of sufficient free atoms and
      a high temperature flame must be used.
      Nitrous oxide produces a hot flame and
      presents  little danger from explosion.
                  Table 1
    Fuel-Oxidant
Approximate
 Temp.,C
Nitrous Oxide -  acetylene         3000

Hydrogen - air                   2100

Hydrogen - oxygen         2700 - 2800

Acetylene - oxygen                3100

Acetylene - air            2000 - 2200

Propane  - oxygen          2700 - 2800
Illuminating gas - oxygen          2800

Cyanogen - oxygen                4900
      There are also two types of burners
      used,  a) "Total Consumption, "  b)
      "Premix. "

      a  The total consumption type is used
         for flame work, and is shown in
         Figure  3,  This burner is often used
         in a series  of three, and by the use
         of mirrors  the beam is reflected
         three to five times through the flame
         to increase  the path length.

      b  The premix burner is the type used
         by Walsh and co-workers in their
         development work. This burner has
         a 10 cm X 1 cm slot and the light
         path makes  only one pass through the
         flame (Figure 4).  The advantages
         are that the flame is narrower, giv-
         ing a larger concentrate of sample
         in the flame.  Since in the premix
         burner  only the vapor  reaches the
         flame,  light scattering by droplets
         and clogging by salts is avoided.
                               L
                                                                               FUEL
OXYGEN
                                 t
                              SAMPLE
                                       Figure 3


                        C  Line Isolation

                           The use of a line spectrum of the element
                           being determined, rather than a continuous
                           spectrum, makes possible the use of
                           monochromators of low resolving power
                           or  even filters.  When a spectral lamp
                           is used as a light source, it is only
                           necessary to isolate the resonance line
                           from neighboring lines of the  light source
                           or vaporized sample.

                        D  Detector

                           Photo-electric detectors used in atomic
                           absorption analysis need be no more sensi-
                           tive than those used in emission analysis,
                           since in the atomic absorption method, con-
                           centration of an element is determined by
                           measuring the  reduction in intensity of the
                           resonance line emitted from a source of
                           high intensity.
                                                                                    36-3

-------
Atomic Absorption Spectrophotometry
                UJ
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36-4

-------
                                                       Atomic Absorption Spectrophotometry
IV COMPARISON OF ATOMIC ABSORPTION
   WITH FLAME METHODS
 A Sensitivity
B
                       Sensitivity mg/1
                     Flame           A. A
Aluminum
Antimony
Arsenic
Barium
Beryllium
Bismuth
Cadmium
Calcium
Cesium
Chromium
Cobalt
Copper
Gallium
Gold
Imdium
Iron
Lead
Lithium
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Palladium
Platinum
Potassium
Rhodium
Rubidium
Selenium
Silver
Sodium
Strontium
Tellurium
Titanium
Thallium
Tin
Vanadium
Zinc
Precision
1 Precision
2

0.3
25
2
0.003

0. 1

0.01


0.2
2
0.002
0. 1
0.01
10


0.001



0.05
0.002
0.01





200

of a single-beam
0.5
0.2
1.0
1.0
0.05
0.2
0.01
0.01
0.05
0.01
0. 15
0.005
1.0
0. 1
0.5
0.05
0. 15
0.005
0.003
0.01
0.5
0.2
0.05
1.0
0.5
0.005
0.3
0.02
1.0
0.02
0.005
0.02
0.5
1.0
0.2
2.0
0.5
0.005

atomic ab-
      sorption instrument is primarily a
      function of the stability of light output
      from the spectral lamp. This in turn is
      dependent on the stability of the main
      supply and inherent stability of the
      lamp.  The largest fluctuations are
      only + 2 percent for the hollow cathode
      tube and sodium spectral vapor lamp.
      A double-beam instrument significantly
      reduces this error.

   2  In common  with flame-emission methods,
      atomic  absorption  is subject to "noise"
      from the  flame and the detector. Changes
      in absorption caused by fluctuations in
      flame temperature are much less than
      those in emission because the strength
      of the absorption line varies only as
      T 1/2,  whereas the intensity of emission
      from the flame is much more sensitive
      to temperature.

C  Accuracy

   This is shown  by the types of interference
   found in flame emission and atomic ab-
   sorption spectroscopy.  There are three
   types:

   1  Physical

      Collision of atoms and electrons or
      atoms and molecules will transfer
      energy  thus causing an enhancement  or
      depression  of analysis-line emission.
      This has  a large effect on flame emission
      analysis but has only a negligible effect
      on atomic absorption.

   2  Radiative

      Light from  elements  other than the one
      being measured pass the line isolating
      device (monochromator or filter). This
      occurs  in flame emission work,  for
      example, the interference of calcium
      and magnesium in  sodium determinations.
      This  interference is  also encountered in
      atomic  absorption  using a D. C. system
      but is very small because of the large
      signal from the hollow-cathode tube.
      Radiative interference is eliminated  in
      an A. C. system.

   3  Chemical
      Emission from an  element in the  flame
      is depressed by the formation of
                                                                                       36-5

-------
Atomic Absorption Spectrophotometry
                         50     100    150     200    250    300     350    400
                                          METAL, ppb
                                         Figure 5
      compounds,  which are not dissociated
      at flame temperatures.  This also
      affects absorption because the formation
      of temperature - stable compounds
      in the flame  causes proportionate re-
      duction in the population of ground-state
      and excited atoms.
V  REMOVAL OF INTERFERENCES AND
   CONCENTRATION OF SAMPLE

A  Removal of Interferences

   1  The methods for overcoming these inter-
      ferences in atomic absorption are similar
      to those used in flame emission, namely,
      either separation of interfering ions or
      suppression of the  interference by ad-
      dition in excess of  a substance that will
      prevent formation of compounds between
      interfering ions and the element being
      determined.

B  Concentration of Sample

   1  Organic separations can be used to con-
      centrate a sample. Interferences are
      removed,  as seen above, and also the
      organic solvent enchanses the absorption.
    2  Ion exchange has also been used
       successfully for concentrating samples
       for atomic absorption.
VI  INSTRUMENTS AVAILABLE

 A Perkin Elmer

    1  Model 303 - double beam, AC - $5, 920. 00

    2  Model 290 - single beam, AC - $2, 900. 00

 B Beckman attachments for existing
    spectrophotometers.

    1  Use with model D. U.  and D. U. -2 -
       single beam,  DC  - $2, 135. 00

    2  Use with model D. B.  - single  beam,
       AC - $2,495.00

 C Jarrell-Ash

    1  Dual atomic absorption flame spect-
       trometer - single beam,  AC - $5, 800.00

 D E. E.L.

    1  Atomic absorption spectrophotometer -
       single beam,  AC  $2, 850.00.
36-6

-------
                                                     Atomic Absorption Spectrophotometry
REFERENCES
1  Walsh, A.  Spectrochim.  Acta. 7, 108. 1955.

2  Kahn, Herbert and Slavin, Walter.  Atomic
     Absorption Analysis.  International
     Science and Technology.  November 1962.

3  David,  D. J.  The Application of Atomic
     Absorption to Chemical Analysis. The
     Analyses. 85:779-791.  1960.
4  Platte, J. A., and Marcy,  V.M.   A New
      Tool for Water Chemicals.  Industrial
      Engineering. May 1965.

5  Biechler, D. G.  Determination of Trace
      Copper,  Lead, Zinc, Cadmium,  Nickel,
      and Iron in Industrial Waste Water by
      Atomic Absorption Spectrophotometry
      After Ion Exchange on Dorvex A-l.
      Analytical Chemistry, 37:1054- 1055.
      1965.

6  Elwell, W. T., and Gidley, J. A. F.  Atomic-
      absorption Spectrophotometry.  The Mac-
      Millan Company. N. Y.  1962.
                                                                                      36-7

-------
                           AUTOMATION OF CHEMICAL ANALYSIS
                                    Lawrence J. Kamphake*
 I  NEED FOR AUTOMATED ANALYSIS

 A At least 30 samples per week for any
    particular analysis.

 B The more complex and manipulating time
    required for manual method the greater
    the advantages to automate.

 C Simple manual methods requiring one
    titration or instrument reading may be
    faster manually unless there are more
    than 100 samples per work day.
 H  DEGREE OF AUTOMATION

 A Maximum automation - direct from sampl-
    ing source to print-out of results of
    multiple analysis.

 B Medium automation - individual samples,
    instrumental analysis, recording and
    calculating data.

 C Minimum  automation - simplicity and
    efficiency in manual analysis.

Ill  PRESERVATION OF SAMPLES

 A Biological and Chemical Stability

    1  Store at 5C, quick freeze

    2  Low pH

    3  Chloroform  1%

    4  Mercuric chloride 100 mg/1

    5  Formalin 500 mg/1

    6  Potassium cyanide 50 mg/1

    7  Thymol 250 mg/1

IV  AUTOMATED INSTRUMENTATION

 A Sensory
    1  Titrimetric

    2  Potentiometric

    3  Photometry  - flow through cells

       a  Visible range

       b  Ultra violet range

       c  Flame

    4  Polarographic - DO

    5  Others as  coulometric,  conducto-
       metric, etc.


 V  MANUAL SYSTEM WITH INSTRUMENTS

 A  Automatic pipettes and burettes and
    reagent dispensers

 B  Electrical on and off timers

 C  Glassware, test tubes vs. volumetric
    flasks

 D  Small volumes

 E  Combining reagents


VI  CONTINUOUS FLOW  SYSTEMS

 A  Pumping Systems

    1  Peristalic

    2  Piston

    3  Vibrator

 B  Reagent Addition

 C  Removal of Interferences

    1  Filtration

    2  Dialysis
 *Chemist,  Engineering Section,  Basic and Applied Sciences Branch,  DWSPC, SEC.  Reviewed
 December  1965.
 CH. MET. 23. 12.64
                                       37-1

-------
  Automation of Chemical Analysis
     3 Distillation

     4 Chemical complexation

     5 Extraction

  D  System Hydraulics

     1  Tubing and glassware

     2 Mixing

     3 Temperature control

     4 Time control

     5 Digestion


VI   RECORDERS

  A  Meters

  B  Chart paper, single pen and multi pens

  C  Print-out data


VH  TECHNICON CORP.  - AUTO-ANALYZER

  A  Equipment and Principle

  B  Adaption of Standard Methods to
     Auto-analyzer

     1  Sensitivity

     2 Wash-out

     3 Chemical reaction and control

  C  Methods currently in use

     1  ABS

     2 Ammonia nitrogen

     3 Nitrite and nitrate nitrogen

     4 Phosphate

  D  Advantages of Auto-Analyzer

     1  Speed - automatic clocks
   2 Small volume of sample required

   3 Removal of human error

     a  Timing reactions

     b  Reading spectrophotometers

     c  Error in pipetting, recording,  etc.

   4 Permanent record of data

   5 Ease of checking every 10 or 20
     samples against standards

   6 All samples treated exactly the same

   7 Use of  chemical methods which
     cannot  be used manually.

E  Disadvantages

   1 Acceptable manifold

   2 Loss of accuracy in determination of
     a low concentration when proceeded
     by a high concentration (50 fold)

   3 Wash-out difficulty

   4 Mechanical failure

   5 Pump tubes

F  Gradient dilution technique

G  Influent and effluent pumped at same rate

                       -rt
        Ct =  C1 (1 - e -v-  )


        C  =  cone, of influent

        Ct =  cone, effluent at t time

          t  =  time (min.)

          r  =  pumping rate (ml/min)

          v  =  volume in flask
   37-2

-------
                                                         Automation of Chemical Analysis
H  Simultaneous Analysis of Nitrite and
   Nitrate

   1   History and chemistry

   2   Manifold

   3   Variables investigated

   4   Accuracy and precision


REFERENCES

1  Muller,  R. H.  Fully Automatic Titrator
      Has Varied Applications.  Anal.  Chem.
      29, 61 A.  1957.
2  Patterson,  G. D.,  Jr.  Automatic Opera-
      tions in Analytical Chemistry.  Anal.
      Chem. 29. 605.  1957.

3  Ibid. Anal.  Chem. 31. 646.  1959.

4  Ryland, A. L.,  Pickhardt, W. P. , and
      Lewis,  C.D.  Automation  Techniques
      in Analytical Chemistry.  E.I.  duPont
      de Nemours & Co.  Wilmington, Del.

5  Kamphake,  L. J.  Simultaneous Analysis
      of Nitrite and Nitrate in Water and
      Sewage.   In Press,  R. A.T.  Sanitary
      Engineering Center. Cincinnati, Ohio.

6  Automatic Chemical Analysis.  Annals of
      the New  York Academy of  Science.
      Vol.  87. Art 2.  1960.
                                                                                     37-3

-------
                             ANALYTICAL REFERENCE SERVICE

                                      Earl F.  McFarren*
 I  INTRODUCTION

 The Analytical Reference Service designs and
 conducts cooperative studies as a means of
 evaluating laboratory methodology in the
 field of the environmental sciences and
 engineering.   Identical samples are dis-
 tributed to the member agencies desiring to
 participate in any particular study.  Inter-
 pretation of the data resulting from  such
 analyses,  together with critiques of the
 methods employed, provide a basis  for such
 evaluation.  Initially directed toward exam-
 ination of water,  the studies have been
 broadened to include other media.

 The Service provides a means of communi-
 cation among  an increasing number  of
 agencies whose investment in laboratory
 operations is large.   For these  agencies it
 also provides an  opportunity for develop-
 mental study of newer procedures commen-
 surate with the demands of our increasingly
 complex environment.  The information
 resulting from these studies is being utilized
 more  and more by groups responsible for
 establishing standard methods.
II  MEMBERSHIP

 Membership in the Analytical Reference
 Service is voluntary and open to all agencies
 having laboratory activities in the field of the
 environmental sciences and engineering.  It
 includes Federal, state, municipal, univer-
 sity, industrial and foreign agencies.  The
 current membership of approximately 205
 agencies includes 27 foreign members.
in  OBJECTIVES

 Through this organization, the cooperative
 efforts of the Analytical Reference Service
 are directed toward the following objectives:
    Statistical evaluation of procedures,
    including precision and accuracy.
    Comparison of analytical procedures
    and results between laboratories having
    similar responsibilities.

    Exchange of information regarding
    method weaknesses.

    Improvement of existing methods or
    development of newer,  more accurate
    methods to replace current procedures.

    Development and evaluation of entirely
    new methodology for the determination
    of new pollutional components, such as
    pesticides, trace  elements, heavy
    metals and air contaminants.
IV  OPERATION

  Studies are selected on the basis of their
  importance, of the need to evaluate labora-
  tory methods,  the availability of satisfactory
  procedures, requests from member agencies,
  and the need of members to re-evaluate
  their own laboratory operations.

  Samples are designed and prepared to contain
  measured amounts of  selected constituents
  in the range of concentrations normally
  encountered in the environment.  Decisions
  as to qualitative makeup are made by the
  ARS staff, the membership, and consultants.

  Notice of each study is forwarded to members
  with information regarding the qualitative
  makeup and special instructions for sample
  treatment.  Portions of the sample are
  shipped to those members who indicate a
  desire to participate in the study.  Accom-
  panying data forms provide space for numeri-
  cal analytical values and  a narrative critique
  of the procedures used.   Laboratories  are
  urged to comment on the  methods, difficulties,
  modifications, sources of error,  and other
  factors.
 *Chief,  Analytical Reference Service, Training Program, SEC.

 CH. ARS. If. 12.65                                                                        38-1

-------
Analytical Reference Service
V  STUDIES COMPLETED

Water Minerals Calcium, magnesium hard-
ness, sulfate, chloride,  alkalinity, nitrite,
nitrate, sodium and potassium.

      Conducted in 1956  - 19 Participants
      Conducted in 1958  - 31 Participants
      Conducted in 1961  - 69 Participants

Water Metals Lead,  copper, cadmium,
aluminum, chromium, iron, manganese and
zinc.

      Conducted in 1957  - 16 Participants
      Conducted in 1962  - 66 Participants

Water Metals Lead,  copper, cadmium,
aluminum, chromium, iron, manganese,
zinc and silver.

      Conducted in 1965  - 79 Participants

Water Fluoride Fluoride in the presence and
absence of interferences with and without
distillation, using a specified procedure.

      Conducted in 1958  - 27 Participants
      Conducted in 1961  - 53 Participants

Water Radioactivity  Determination of gross
beta activity.

      Conducted in 1959  - 25 Participants
      Conducted in 1961  - 41 Participants

Water Radioactivity  Determination of Gross
beta and Strontium-90 activity.

      Conducted in 1962  - 80 Participants

Water Surfactant Surfactant in various
waters.

      Conducted in 1959  - 42 Participants
      Conducted in 1963  - 82 Participants

Water Oxygen-Demand Biochemical oxygen
demand and chemical oxygen demand.

      Conducted in 1960  - 35 Participants
      Conducted in 1964  - 78 Participants
Air Inorganics  Chloride,  sulfate,  fluoride,
and nitrate in aqueous solution and on glass
fiber hi-vol filter mats.

      Conducted in 1958 - 20 Participants

Air Lead  Lead on filter paper tape.  Sample
was designed to approximate pollution from
motor vehicles.

      Conducted in 1961 - 42 Participants

Air Participates Microscopic identification
of some common atmospheric particulates.

      Conducted in 1964 - 28 Participants

Air Sulfur Dioxide Determination of sulfur
dioxide in air using a specific method.

      Conducted in 1962 - 43 Participants

Water Trace-Elements Arsenic, boron,
selenium, and beryllium.

      Conducted in 1962 - 29 Participants

Water Trace-Elements Arsenic, boron,
selenium, beryllium and vanadium.

      Current study - 92 Participants

Milk DDT - Residue

      Conducted in 1962 - 14 Participants

Freshwater Plankton Evaluation of the pre-
cision and accuracy obtainable by using
various methods of plankton counting and
analysis.

      Conducted in 1963 - 47 Participants

Pesticides in Milk Dieldrin, DDE, heptachlor
epoxide and lindane.

      Conducted in 1965 - 42 Participants

Pesticides in Water  Dieldrin,  DDE, heptachlor
epoxide and lindane.

      Conducted in 1965 - 29 Participants
38-2

-------
                                                                  Analytical Reference Service
. VI  REPORTS                                    VII  PROJECTED STUDIES

  The results and comments of each study are        Studies in the developmental or proposed
  compiled into a comprehensive report which        stage include water nutrients and an air
  is distributed to all members. It is this report      inorganics or sulfur dioxide  study.
  which provides the means of comparison and
  evaluation of the results and techniques.
                                                                                          38-3

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