United States
Environmental Protection
Agency
Environmental Research
Laboratory
Athens G A 30613
Research and Development
EPA-600/S4-82-072 Mar. 1983
&ERA Project Summary
Analysis of Chlorinated Organic
Compounds Formed During
Chlorination of Wastewater
Products
W. H. Glaze, J. L Burleson, J. E. Henderson IV, P. C. Jones, W. Kinstley, G. R.
Peyton, R. Rawley, F. Y. Saleh and G. Smith
Chemical by-products produced dur-
ing the Chlorination of municipal waste-
water were examined in a study that
employed several specially modified
analytical methodologies. Volatile by-
products were examined with the use of
gas chromatography with selective de-
tectors and gas chromatography/mass
spectrometry (GC/MS). With the use of
XAD resins for concentrating trace
organics hi the wastewater samples
before and after Chlorination, a number
of chlorinated aromatic and aliphatic
compounds were found after Chlorin-
ation and superchlorination.
A rapid and convenient microextrac-
tion method was developed that is
suitable for analyzing trihalomethanes
and other volatile halogenated organics
at the microgram-per-liter level in
water. Also, a computer program was
developed that may be used in con-
junction with a GC/MS computerized
data system to identify polyhalogenated
compounds present as minor compo-
nents of a complex chemical mixture. A
procedure was also developed to de-
termine the concentrations of amino
acids in wastewaters, sludges, and
septage before and after Chlorination.
Two chlorinated derivatives of tyrosine
were found in a superchlorinated sep-
tage sample.
Non-volatile compounds in natural
waters and municipal wastewaters,
before and after Chlorination. were
studied with the use of high perform-
ance liquid chromatography. Fractions
collected before Chlorination of the
sample showed that trihalomethane
formation potential was spread
throughout the natural polymer. After
Chlorination, total organic halides of
a non-volatile nature were determined
by adsorption of the organics on either
XAD resins or powdered activated
carbon (PAC) followed by elution of the
resin and combustion of the eluate or by
direct combustion of the PAC. In both
cases, it was found that organic
halogen was spread throughout the
natural polymer, although Chlorination
at the levels used (20-30 mg/L) did not
much affect the average molecular
weight of the polymer.
This Pro/act Summary was developed
by EPA's Environmental Research Lab-
oratory, Athens. GA, to announce key
findings of the research project that is
fully documented in a separate report of
the same title (see Project Report order-
ing information at back).
Objectives
This report describes a series of studies
that examined the chemical by-products
formed during the Chlorination of mu-
nicipal wastewater effluents. When the
research began in 1974, little was known
about this subject; since then, the ques-
tion of by-products formed during the
Chlorination of all types of waters has
been investigated extensively. It is now
well established that by-products are
produced whenever chlorine is used as a
disinfectant or a biocide. Among these
-------
arethetrihalomethanes, now the subject
of regulations that limit their concen-
tration in drinking water.
The objectives of the research reported
here were:
1. to develop methods for separating
and identifying the types and quan-
tities of volatile by-products produced
during the chlorination of water,
particularly municipal wastewater
after secondary treatment. Central to
this effort was the evaluation of XAD
resins for concentrating trace organ-
ics in water and the use of gas
chromatography with selective detec-
tors and gas chromatography/mass
spectrometry (GC/MS) for elucidat-
ing the structures of these sub-
stances.
2. to develop separation methods based
on hig'h performance liquid chroma-
tography (HPLC) for the study of
wastewater effluents and natural
waters before and after chlorination.
The purpose of these studies was to
extend our knowledge about non-
volatile compounds in water and, in
particular, to determine whether
halogenated non-volatile compounds
are produced during chlorination of
water and wastewater.
3. to investigate the chlorinated by-
products produced when very large
doses of chlorine (1000-3000 mg/L)
are used to treat wastewaters,
sludges, and septage. The use of
such high doses has been proposed
as a method for disinfecting and
stabilizing septage and sludge and as
a possible alternative wastewater
treatment scheme for small systems.
Volatile By-Products of Super-
chlorination of Wastewater Prod-
ucts
Samples investigated in this study
included raw municipal sewage, sec-
ondary municipal effluent, anaerobic
digestor supernatant, combined sludges,
and septage. In most cases, by-products
examined were from the chlorination of
these samples using 1000-3000 mg/L
chlorine, but chlorinated by-products
were also found in samples chlorinated
with lower doses. Volatile by-products
identified included a series of polychlo-
rinated phenols, chloroform, chlorinated
benzenes and alkyl benzenes, polyhalo-
genated acetones, and other aliphatic
halides (Table 1). In a separate study, the
chlorination of amino acids in municipal
wastes was also examined with
emphasis on determining chlorinated by-
Table 1. Summary of Chlorinated Organics Found in Superchlorinated Municipal Wastewate,
Compound
Number
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
31
32
33
34
35
36
37
38
39
Compound Name*
Chloroform
Dibromochloromethane
Dichlorobutane
3-chloro-2-methylbut-1 -ene
Chlorocyclohexane (1 18)
Chloroalkyl acetate
o -Dichlorobemene
p-Dichlorobemene
Chloroethylbenzene
Tetrachloroacetone
Pentachloroacetone
Hexachloroacetone
Trichlorobenzene
Dichloroethylbenzene
Chlorocumene (154)
N-methy/-trichloroaniline (209)
Dichlorotoluene
Trichlorophenol
Chloro-a-methyl benzyl alcohol
Dichloromethoxytoluene
Trichloromethylstyrene (220)
Trichloroethylbenzene (208)
Dichloro-a-methyl benzyl alcohol (190)
Dichloro - b i sfethoxyjbenzene (220)
Dichloro-a-methyl benzyl alcohol (190)
Trichloro-N-methylanisole
Trichloro-a-methyl benzyl alcohol
Trichloro-a-methyl benzyl alcohol
Tetrachlorophenol
Trichloro-a-methyl benzyl alcohol
Trichlorocumene (222)
Tetrachloroethylstyrene (268)
Trichlorodimethoxybenzene (240)
Tetrachloromethoxytoluene (258)
Dichloroaniline derivative (205)
Dichloroaromatic derivative (249)
Dichloroacetate derivative (203)
Trichlorophthalate derivative (296)
Tetrachlorophthalate derivative (340)
Identifi-
cation
Status
1.9
1.9
d.g
1
d,g
d
f
f
e
e
f
f
f
f
d.g
d.g
e.g
e
e.g
e.g
d.9
d.g
d
d.g
d
e.g
e
e
f
e
d
d
d
d
c
c
c.g
c
c
Concen-
tration''
//g/L
-
27
285
20
-
10
10
21
11
30
30
-
20
-
10
-
-
-
32
10
12
10
30
-
-
25
25
30
50
-
-
-
4
13
15
20
-
~
"Compounds may be listed more than once if GC retention times indicate distinct positional
isomers.
^Quantitative vahies should only be considered as estimates, because response factors and
recovery data were not available for our extraction system.
"Mass spectra I information is too incomplete to propose a structure; probable molecular weight
is indicated in parentheses.
''Fragmentation pattern tentatively suggests proposed compound; probable molecular weight
is indicated in parentheses.
'Probable identification is based on mass spectral interpretation.
'Completed identification is based on MS interpretation and confirmed by comparison with a
reference spectrum.
'Compounds.were identified in runs other than November 12, 1974.
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products. Chloro- and dichlorotyrosine
were found in a superchlorinated septage
sample, and other neutral products were
also characterized.
432/0
Retention Volume (mL)
Figure 1. Size exclusion chromatograms
of Cross Lake sample, freeze
dried water soluble fraction. A.
unchlorinated; B, chlorinated at
20 mg/L for five days.
With the exception of the studies
searching for amino acid by-products, the
separation procedure used in these inves-
tigations was XAD resin adsorption,
followed by ether elution, evaporative
concentration, and GC analysis. Selective
detectors(halogen-sensitive Coulson elec-
trolytic conductivity and electron capture)
and GC/MS were used for identifying
halogenated by-products.
Amino acids were concentrated by
sequential adsorption/elution from
DOWEX 50W-X8 and Chelex-100 resins,
followed by derivatization to the N(0)-
heptafluorobutyryl n-propyl (or /so-amyl)
esters. Identification and quantification
was with GC/MS. Amino acids in raw
and chlorinated municipal wastewater
determined by this method, were com-
pared with levels determined by a Beck-
mann amino acid analyzer with generally
good agreement.
Non-Volatile By-Products of Chlo-
rination of Natural Waters and
Wastewaters
Two methods were used to investigate
non-volatile by-products: an adsorption-
combustion-microcoulometric procedure,
which sought to measure total organic
halides (TOX), and a series of HPLC-based
procedures with various detectors, includ-
ing manual collection of fractions for
TOX, dissolved organic carbon (DOC), and
trihalomethane formation potential
(THMFP) measurements. (THMFP meas-
ures the potential of naturally occurring
organics to form trihalomethanes upon
chlorination. The ratio of THMFP to DOC
is a measure of this potential normalized
to the organic content of the sample.)
Samples included a secondary munic-
ipal wastewater effluent and water from
a reservoir in western Louisiana (Cross
Lake). The non-volatile organic com-
pounds were isolated by freeze drying
and redissolved to obtain fractions soluble
in neutral, acid, or base solutions. Further
fractionation of the neutral fraction by
size exclusion HPLC showed that chlo-
rination changes the molecular weight
profile of the natural polymer only slightly
(Figure 1). Moreover, before chlorination,
trihalomethane formation potential is
spread through the molecular size range
of the polymer (Table 2). Fractionation of
the polymer after chlorination showed
that the non-volatile organic-bound halo-
gen (NVTOX) is also spread throughout
the polymer (Table 3). These results show
that the potential for forming THMs and
other halogenated by-products is most
likely a characteristic of the organics in
natural waters, and moreover, that floe-
culation techniques are not likely to
remove THMFP entirely.
Fractionation of the freeze-dried acid
soluble fraction of the natural polymer
with a weak anion exchange resin with
pH gradient elution produced fractions in
three separate pH regions (Figure 2).
Model compound studies suggest that
one of these fractions has a pK« value
similar to that of phenols, and another,
the pK. value of hydroxybenzoic acids.
The nature of the third fraction, which
occurs to various extents in waters from
different sources, is unknown.
Tibia 2. Characteristics of the Water Soluble Fractions of Cross Lake Water Collected by Site Exclusion HPLC (Unchlorinated)
Fraction
Number
1
2
3
4
S
Average
Sum
Molecular Weight flange
31.6x10*-
22.3 x JO3 -
19.1 x 10*-
15.9 x 10s -
6.3 x 103 -
10.5 x
15.9 x 10*
7.9x10*
7.1 x 10*
5. 1 x 103
0.2 x 10*
10*
Molecular Weight
at Pk Maximum
22.4 x 10*
14.2 x 10*
10.3 x 10*
7.9 x 10*
3.9 x 10*
DOC'
X
0.63
0.93
1.28
1.22
0.91
4.97
(mg/L)
S*
O.O4
0.00
0.04
0.20
0.20
THMFP' (ug/L)
X S*
31
73
7
2
95 1O
43
62
304 (252 as
5
2
CD
THMFP*
DOC
X Sb
.049
.078
.074
.035
.068
.061
.011
.002
.008
.004
.002
.005
'DOC - Dissolved Organic Carbon.
"S = Standard Deviation.
"THMFP = trihalomethane formation potential using a chlorine dose of 20 mg/L, 3 days, pH 6 5
"Units of THMFP/DOC in mg THMFP/mg C.
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Tibli 3. Characteristics of the Water Soluble Fractions of Cross Lake Water Collected by Size Exclusion HPLC (Chlorinated*)
Fraction
Number
1
2
3
4
5
Average
Sum
Molecular Weight Range
31.6 x103-
19.1 x103-
15.9 x 103-
1 2.6x1 03-
7.1 xW3-
8.2 x
14.2 x
6.9 x
6.3 x
2.2 x
0.1 5 x
103
JO3
103
103
W3
103
Molecular Weight
at Pk Maximum
19.1 x
12.6 x
7.1 x
3.9 x
2.5 x
JO3
W3
W3
W3
W3
DOC
X
1.04
0.98
1.00
0.64
0.52
4.18
(mg/L)
S"
0.48
0.16
0.36
0.08
0.04
NVTOX°
X
65
47
86
20
42
260
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W. H. Glaze, J. L Burleson, J. E. Henderson IV. P. C. Jones, W. Kinstley. G. R.
Peyton, ft. Rawley, F. Y. Saleh, and G. Smith are with North Texas State
University, Demon, TX 76203.
A. W. Garrison is the EPA Project Officer (see below).
The complete report, entitled "Analysis of Chlorinated Organic Compounds
Formed During Chlorination of Wastewater Products," (Order No. PB 83-144
444; Cost: $17.50, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Research Laboratory
U.S. Environmental Protection Agency
College Station Road
Athens, GA 30613
*USGPO: 1983-659-095-593
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