SURROGATE AND MATRIX SPIKE RECOVERIES IN CHLORINATED
SAMPLES USING SODIUM THIOSULFATE, SODIUM ARSENITE AND
L-ASCORBIC ACID AS DECHLORINATING AGENTS
Susan C. Warner and Joseph L Slayion
Environmental Protection Agency
Central Regional Laboratory
839 Bestgate Road
Annapolis, Maryland 21401
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SURROGATE AND MATRIX SPIKE RECOVERIES IN CHLORINATED
SAMPLES USING SODIUM THIOSULFATE, SODIUM ARSENITE AND L-ASOORBIC
ACID AS DECHLORINATING AGENTS*
Susan C. Warner and Joseph L. Slayton
U.S. Environmental Protection Agency
Central Regional Laboratory, Region III
839 Bestgate Rd., Annapolis, Md. 21401
301-266-9180
Method 625 (Base/Neutrals and Acids) (1) states that
samples containing residual chlorine must be dechlorinated
using 80 mg of sodium thiosulfate per liter of sample
(Section 9.2) at the time of sampling. Field conditions are
difficult to control and it is conceivable that excess
amounts could be added. Analytical problems have been
encountered using this reagent when excess thiosulfate has
been added to samples. Sulfur crystal formation occurred in
the Kuderna-Danish concentration process and caused frothing
of the concentrate. This can easily cause the sample to go
to dryness. Also, the elution of molecular sulfur caused
severe chromatographic interferences. These problems were
especially evident when the samples were extracted using
continuous liquid/liquid extraction. The sulfur formation
occurred under acid (pH<2) extraction conditions as a result
of the decomposition/disproportionation of thiosulfate to
sulfur and sulfite/sulfur dioxide (2).
Two alternate dechlorination agents were tested:
L-ascorbic acid and sodium arsenite. Both were efficient at
reducing the chlorine. Sodium arsenite treatment resulted in
a clean chromatogram and no analytical problems. L-ascorbic
acid treatment generated five chromatographic interference
peaks when the extraction was performed with the continuous
extractor. These were: 2-furanca.rboxylic acid; 3-furan-
carboxylic acid, methyl ester; 2-furancarboxaldehyde;
3,5-dihydroxy-2-methyl-4H-pyran-4-one; and one unidentified
peak. These five compounds were tentatively identified using
the EPA-NIH spectral library. The mass spectrum of 2-furan-
carboxylic acid contained a fragment with mass 45 amu and
would be expected to elute near bis(2-chloroisopropyl)ether.
The base peak of this priority pollutant is also 45 amu.
This contaminant could cause a positive interference which
should be resolvable by manual quantitation or by reducing
the automated target search windows. No contaminating peaks
were detected when samples were dechlorinated with L-ascorbic
acid and extracted using separatory funnels.
Sodium arsenite is listed as extremely toxic to humans
with an oral lethal dose of less than 5 mg/kg (3), and would
be too dangerous for routine field use. L-ascorbic acid is
-------
non-toxic and is more soluble in water than sodium arsenite.
L-ascorbic acid has been recently recommended as a
dechlorinating agent of choice for VOCs (EPA QA Newsletter,
January, 1988) (4), and it would be convenient to use the same
material to dechlorinate samples for extractable organics.
However, low recoveries (about 30% of a 50 ug/L spike) of
2,4-dinitrotoluene were obtained when the extraction was
carried out in the presence of excess L-ascorbic acid using
Method 625 (continuous extraction).
*This work was first presented in the EPA Quality Assurance
Newsletter, July 1988, Volume 10, Number 2.
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Disclaimer:
The mention of trade names or commercial products in this
report is for illustrational purposes and does not constitute
endorsement or recommendation by the U.S. Environmental
Protection Agency.
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TABLE OF CONTENTS
Pages
I. Introduction 1-2
II. Reagents and Supplies 3
III. Standard Preparation 3-5
IV. Apparatus and Materials 6-7
V. Procedure 8-13
VI. General Quality Control 14
VII. Experiment-Specific Quality Control 15-16
VIII. Results and Discussion 17-47
IX. Conclusion 48-49
X. References 50-51
XI. Appendix 52-76
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I. INTRODUCTION
Chlorine reacts with various organics in environmental
samples to produce undesirable artifacts. These artifacts
can cause false positives to be reported, and other compounds
actually present to be reported as not detected. For
example, phenol concentrations may decrease in chlorinated
effluents, forming various mono- and poly- chlorinated
phenols. When phenols are reacted with aqueous solutions of
halogens, polyhalogenation of the phenolic ring occurs (5).
On the other hand, monohalogenated compounds are the primary
products formed if the reaction occurs in a non-polar solvent
such as carbon tetrachlofide or chloroform (5). Reactions in
methylene chloride could be expected to produce a similar
reaction.
The NPDES method (EPA Method 625) (1) for base/neutral
and acid compounds states that residual chlorine should be
determined in the field. Any residual chlorine present is to
be removed using 80 mg of sodium thiosulfate per liter of
sample. The EPA Newsletter of January 1988 contained a "Note
on Preservation of Drinking Water Samples to be Analyzed for
Volatile Organic Chemicals (VOCs) and 1445 Monitoring
Compounds" (4). This note stated that effluents must be
dechlorinated before acidification to prevent the chlor-
ination of compounds present in the effluent. It was
reported that when sodium thiosulfate was used as a de-
chlorinating agent for VOA analysis, SO2 interfered with the
early-eluting VOA gases. Ascorbic acid was recommended as a
substitute. It did not produce any chromatographic
interferences.
This study examined the suitability of three
dechlorinating agents: sodium thiosulfate, L-ascorbic acid
and sodium arsenite. In the initial series of experiments,
EPA Method 625 (1) (continuous extraction option) was used
for the analysis. One variation to the method was employed;
base/neutral and acid extracts were combined before GC/MS
analysis. A second series of experiments were also performed
using acid/neutral extraction conditions (continuous
extraction) followed by a basic extraction. Base/neutral.
acid refers to an extraction scheme in which the sample pH
is first adjusted to pH >11. This results in the extraction
of basic and neutral compounds. Fresh solvent is then added,
and the pH is adjusted to <2. Acidic compounds will be
extracted in this fraction. Acid/neutral, base refers to an
extraction scheme in which the sample pH is first adjusted to
pH <2. This results in the extraction of acidic and neutral
compounds. Fresh solvent is then added, and the pH is
adjusted to >11. Basic compounds will be extracted in this
fraction.
The effect of chlorination would be expected to be
intensified under acid/neutral conditions, since chlorine
-------
would be in the free reactive state (6). Under basic
conditions, most of the chlorine would be present as
hypochlorite ion (6).
pH>4
C12 + H,0 <-=> HC1 + HOC1
2 2 PH<4
pH>9
HOC1 <==> H+ + OCL~
pH<9
The three dechlorinating reagents were also tested
using the separately funnel technique. Excess amounts of
each reagent were used to determine analytical problems,
including chromatographic interferences. In a separate test,
160 mg of sodium thiosulfate was employed as a dechlorinating
agent and tested for analytical problems.
The effect of L-ascorbic acid dechlorination was further
tested using spikes of nitrobenzene, 2.4-dinitrotoluene and
2,6-dinitrotoluene. Extractions were performed by the
continuous extraction method.
In a final series of experiments, sodium thiosulfate
was tested using 20 and 80 mg levels of this reagent. Both
levels were tested using continuous extraction. A sep-
aratory funnel analysis using 80 mg/L of sodium thiosulfate
was also performed.
The authors are currently using continuous extraction as
the routine method of extraction for water samples. This
method has been found to generally produce higher recoveries
of all compounds when compared to separatory funnel
extraction (7). The higher recoveries are due to the fact
that the extraction solvent is constantly being re-distilled.
This essentially results in numerous, repeated extractions
using fresh solvent for each extraction.
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II. REAGENTS AND SUPPLIES
Brand names and catalog numbers are included for
illustrational purposes only.
a. Chlorox, commercial brand, 5.25% sodium hypochlorite.
b. Hach DPD Kit, Model # CN-66, containing DPD reagent
total chlorine reagent powder pillows part, #14076-99.
c. Sodium Hydroxide, J.T. Baker, pellet form, #3728-1.
6N NaOH prepared by adding 240 g of NaOH to a 1000 mL
volumetric flask and diluting to volume.
d. Methylene chloride, B & J high purity solvent, product
#300, contains cyclohexene preservative to inhibit HC1
formation.
e. Sulfuric acid, Baker, Instra-Analyzed, #9673-03.
6N H2SO4 prepared by slowly adding 167 mLs of
concentrated H2S04 to 833 mLs of reagent water.
f. Multi-range pH paper strips, EM-Reagents ColorpHast
pH indicator strips, pH 0-14.
g. Boiling Stones, Hengar Co., carborundum #12 granules,
#133-B. Conditioned by muffling at 450°C for 3-4 hrs.
h. Sodium thiosulfate, Baker, anhydrous, granular, #1-3954.
i. Sodium arsenite, meta, Fisher, #5225.
j. L-Ascorbic acid, Fisher, #A-61.
k. Sodium sulfate, anhydrous, granular, Mallinckrodt, product
#8024 . Muffled for 3-4 hours at 450°C. Stored in glass.
1. Glasswool, Pyrex brand, fiber glass, sliver 8 micron,
Corning Glass Works. Muffled for 3-4 hours at 450°C.
III. STANDARD PREPARATION
A. SPIKING SOLUTION PREPARATION
The surrogate spike mix contained the following
compounds (at a concentration of 500 ug/mL, except
tribromophenol which was 1500 ug/mL): 2-fluorophenol;
d5-phenol; d5-nitrobenzene; 2-fluoro-l,l'-biphenyl;
2,4,6-tribromophenol; and d14-p-terphenyl. The following
standards, obtained from the EPA Quality Assurance Materials
Bank in RTP, N.C., were used in the preparation of the
surrogate standard mix:
2,4,6-tribromophenol, #875-01-03, in methanol, 5000 ug/mL
d14-p-terphenyl, #909-03-01, in tetrahydrofuran, 5000 ug/mL
Organics Surrogate Mix, #C088-01, in methylene chloride
contained the following compounds, each present at a
concentration of 5000 ug/mL:
2-fluorophenol 2-fluoro-1,1'-biphenyl
d5-phenol 2,4,6-tribromophenol
d5-nitrobenzene
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The surrogate mix was prepared by pipetting 1 mL of
#C088-01, 2 mLs of 2,4,6-tribromophenol and 1 mL of di4-p-
terphenyl into a 10 mL volumetric flask and diluting to
volume with acetone.
The matrix spike solution for acidic compounds (in
methanol) contained the following compounds at a .
concentration of 1000 ug/mL: phenol; 4-chloro-3-methylphenol;
4-nitrophenol; 2-chlorophenol and pentachlorophenol. The
following standards, obtained from the EPA Quality Assurance
Materials Bank in RTF, N.C., were used in the preparation of
this mix:
Phenol, #63-01-06, in methanol, 5000 ug/mL
4-chloro-3-methylphenol, #20-02-02, in methanol, 5000 ug/mL
4-nitrophenol,-#56-01-06, in methanol, 5000 ug/mL
2-chlorophenol, #22-03-03, in methanol, 5000 ug/mL
pentachlorophenol, #62-03-13, in methanol, 5000 ug/mL
The matrix spike solution for acidic compounds
(hereafter referred to as acid matrix spike) was prepared by
adding 2 mLs of each stock standard to a VOA vial. The
standards diluted each other to a final concentration of 1000
ug/mL.
The matrix spike solution for basic and neutral compounds
contained the following compounds (at a concentration of 500
ug/mL each, except for pyrene which was 100 ug/mL): 1,4-di-
chlorobenzene; n-nitroso-di-n-propylamine; 1,2,4-trichloro-
benzene; acenaphthylene/acenaphthene; 2,4-dinitrotoluene;
di-n-butyl phthalate and pyrene. The following standards,
obtained from the EPA Quality Assurance Materials Bank in
RTP, N.C., were used in the preparation of this mix:
1,4-dichlorobenzene, #25-02-03, in methanol, 5000 ug/mL
n-nitroso-di-n-propylamine, #61-03-02, in methanol,5000 ug/mL
1,2,4-trichlorobenzene, #07-01-08, in methanol, 5000 ug/raL
acenaphthylene, #75-01-04, in methanol, 5000 ug/mL
acenaphthene, #75-02-02, in methanol, 5000 ug/mL
2,4-dinitrotoluene, #33-02-03, in methanol, 5000 ug/mL
di-n-butyl phthalate, #66-01^-07, in methanol, 5000 ug/mL
pyrene, #82-03-01, in methanol, 5000 ug/mL
The matrix spike for basic and neutral compounds
(hereafter referred to as base/neutral matrix spike) was
prepared by adding 1 mL of each standard to a 10 mL
volumetric flask and diluting to volume with acetone.
B. INTERNAL STANDARDS
a. Supelpreme-HC Internal Standards Mix, 4000 ug/mL each
in 1 mL methylene chloride:
-------
d10-acenaphthene d8-naphthalene
d^-chrysene d^-perylene
d4-l,4-dichlorobenzene d10-phenanthrene
All extracts were spiked with the internal standards
mix just prior to GC/MS analysis.
NITROBENZENE AND 2,4-DINITROTOLUENE STANDARD
Prepared by pipetting 1 mL of each of the following into
a 10 mL volumetric flask and diluting to volume with
methanol.
a. Nitrobenzene, #54-01-08, in methanol, 5000 ug/mL
b. 2,4-dinitrotoluene, #33-02-03, in methanol, 5000 ug/mL
Both standards were obtained from the EPA Quality
Assurance Materials Bank in RTP, North Carolina. The
final concentration of the working standard was 500
ug/mL.
2,6-DINITROTOLUENE STANDARD
Prepared by pipetting 1 mL of the following into a 10 mL
volumetric flask and diluting to volume with acetone:
2,6-dinitrotoluene, #606-20-2, in methanol, 5000 ug/mL
This standard was obtained from the EPA Quality
Assurance Materials Bank in RTP, North Carolina. The
final concentration of the working standard was 500 ug/mL.
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IV. APPARATUS AND MATERIALS
a. Muffle furnace, Blue M Power-O-Matic 80.
b. Muffle furnace, Blue M Touch Master, Model #CFD-20F-6.
c. Heating mantle, Glas-Col Apparatus Co., Cat. No. TM102.
d. Variable transformer, Staco Energy Products Co.,
type 3PN1010.
e. 500 mL boiling flask.
f. 1000 mL graduated cylinder.
g. Allinn condenser, 45/50 joint.
h. 3-ball Snyder columns, macro and micro.
i. 500 mL Kuderna-Danish evaporative flask.
j. 10 mL graduated Kuderna-Danish concentrator tube.
k. Continuous extractor, one piece, glass, obtained from Hawk
Creek Laboratory, Glen Rock, Pa. or Perpetual Systems,
Rockville, Md. (see Figure 1) .
1. GC/MS, Finnigan MAT 4500, 70eV electron impact ionization.
m. GC/MS, Finnigan MAT 4023, 70eV electron impact ionization;
n. Fused silica capillary column, 25 m, 0.32 mm. id., 1.0 urn
film thickness, SB-Phenyl-5, Lee Scientific, Salt Lake
City, Utah.
o. Fused silica capillary column, 30 m., 0.32 mm. id;, 1.0 urn
film thickness, SPB-5 (5% diphenyl: 94% dimethyl: 1% vinyl
polysiloxane phases), Supelco, Beliefonte, Pa.
p. Drummond pipet, 100 uL dispensing pipettor, Model #375, used
for pipetting surrogate spike.
g. Gordon-Keeble pipet, 100 uL dispensing pipettor, used for
pipetting matrix spike.
r. Finnigan MAT Incos GC/MS 4500 software, Rev 4.07.82
s. Finnigan MAT Incos GC/MS 4023 software, Rev. 3.1, 01/79
Rev. C.
t. Volumetric pipet, l mL.
u. Volumetric flask, 10 mL.
v. Milli-R015 Millipore System.
w. Screw cap vials with teflon-faced silicone septa, 1.8 mL,
Cat. Nos. 3-3286 (vials) and 3-3210 (caps and septa),
Supelco, Beliefonte, Pa.
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FIGURE 1. LIQUID-LIQUID EXTRACTOR
LL-1000
Perpetual Systems Corporation
IdmtiT* DMtiM
*2SJU«*A»»fwt
•ort lilt. MifyUad M8S1 ODDHMHN
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V. PROCEDURE
A. continuous Extraction
EPA Method 625 fBase/Neutral. Acid Extraction)
Eight deionized water aliquots were chlorinated to
approximately 1 ppm total chlorine using Chlorox. The
chlorine concentration was confirmed by using a Hach DPD
kit (visual comparator method). The DPD method gave a
concentration of 0.7 ppm total chlorine.
Sample 1 was a non-chlorinated deionized water blank.
Two aliquots of one liter each were not dechlorinated
(samples 2 and 3). Samples 4 and 5 were dechlorinated using
sodium thiosulfate. Samples 6 and 7 were dechlorinated using
sodium arsenite. Samples 8 and 9 were dechlorinated using
L-ascorbic acid. The chlorinated aliquots were prepared in
glass gallon jugs. They were then dechlorinated (samples 4-9)
by adding approximately 2.5 grams (to excess) of each
dechlorinating agent to the appropriate jug. Each jug was
then mixed by vigorous manual shaking. This dechlorination
step was verified by using a Hach DPD kit to test for total
chlorine.
Extractions were performed by the continuous extraction
technique. The flow rate in each extractor was ~ 6 mLs/minute,
A Neslab Coolflow refrigerated recirculator was used to cool
the condensers. The temperature of each condenser was 10-15°C.
All extractions were carried out in the dark to prevent
possible photodecomposition of light-sensitive compounds.
200-300 mLs of methylene chloride were placed into each
continuous extractor and 1000 mLs of prepared sample were
added. Each one liter aliquot was adjusted to a pH >11
using 6N NaOH. 100 uL of surrogate was spiked into each
aliquot. An additional 200 mLs of methylene chloride was
added through the water sample, with overflow into the 500 mL
boiling flask. The samples were then spiked with 100 uL of
base/neutral matrix spike (below the surface of the water
sample) and 100 uL of acid matrix spike (above the surface of
the water sample), except samples 1 and 2, in which the acid
matrix spike was spiked below the surface of the water. For
sample 1 (method blank), 200 mLs of methylene chloride was
added through the water sample and then the surrogate,
base/neutral and acid matrix spikes were added in succession.
The surrogate spike mix (in acetone) contained the
following compounds (at a concentration of 500 ug/mL, except
2,4,6-tribromophenol which was 1500 ug/mL): 2-fluorophenol;
d5-phenol; d5-nitrobenzene; 2-fluoro-l,l'-biphenyl;
2 ,'4,6-tribromophenol; and d14-p-terphenyl. The water
samples were spiked with 100 uL of the surrogate spike mix,
resulting in a concentration of 50 ug/L for all compounds
-------
except 2,4,6-tribromophenol which was 150 ug/L.
The acid matrix spike mix (in methanol) contained the
following compounds each at a concentration of 1000 ug/mL:
phenol; 4-chloro-3-methylphenol; 4-nitrophenol; 2-chloro-
phenol and pentachlorophenol. The water samples were spiked
with 100 uL of acid matrix spike mix, resulting in a
concentration of 100 ug/L.
The base/neutral matrix spike contained the following
compounds (at a concentration of 500 ug/mL each, except for
pyrene which was 100 ug/mL): 1,4-dichlorobenzene; n-nitroso-
di-n-prbpylamine; 1,2,4-trichlorobenzene; acenaphthylene;
2,4-dinitrotoluene; di-n-butyl phthalate and pyrene. The
water samples were spiked with 100 uL of base/neutral spike
mix, resulting in a concentration of 50 ug/L for all
compounds, except for pyrene which was 10 ug/L.
The initial base/neutral (pH>ll) extraction time was 24
+ 2 hours. The pH was adjusted with 6N NaOH. The extraction
was then carried out at a pH <2 for 24+2 hours. A fresh
boiling flask was added and the pH was adjusted using 6N
H2S04. After extraction, the base/neutral and acid solvent
fractions were filtered through Na2SO4 and glass wool, and
combined in a Kuderna-Danish apparatus. The extracts were
concentrated to 1 mL methylene chloride in calibrated
concentration tubes using the Kuderna-Danish technique. Micro
Snyder columns were used for the final concentration step
(~ 5 mL to 1 mL). The temperature of the water bath used for
concentration was 65-70°C. Extracts were transferred to
1.8 mL screw cap/septa vials and stored in a freezer until
GC/MS analysis.
A reference standard containing the surrogate and matrix
spike compounds was prepared at the time of extraction.
100 uL each of the surrogate mix, acid matrix spike mix and
base/neutral matrix spike mix were diluted to 1 mL methylene
chloride in a volumetric flask. The sample extracts and the
reference standard were placed into 1.8 mL screw cap/septa
vials. Each vial was spiked with 10 uL of a 4000 ug/mL
internal standard mix just prior to GC/MS analysis. This mix
contained d4-l,4-dichlorobenzene; d8-naphthalene;
d10-acenaphthene; d^ft-phenanthrene; d^o-chrysene; and
d^2~perylene. Each internal standard had a resulting
concentration of 40 ug/mL. .
The extracts and reference standard were analyzed by
capillary GC/MS (70eV electron impact). A Supelco
SPB-5 fused silica column was employed in the Finnigan 4500
GC/MS and an SB-phenyl-5 Lee Scientific fused silica column
was used in the Finnigan 4023 GC/MS. The GC oven temperature
program for both instruments was: 30°C for 2 minutes to
3006C at 10°C/minute. The mass range scanned was 35-450
amu, at a scan rate of 0.8 seconds/scan. Data was acquired
-------
using centroid sampling.
The percent recovery of surrogate and matrix spikes was
determined as follows:
% Rec « na measured in extract X 100
ng measured in reference
B. Continuous Extraction (Acid/Neutral. Base Extraction)
Part 1
A series of experiments was performed by first
extracting the samples at pH <2, followed by an extraction at
pH >11. It was found that this extraction order improved
recovery of short-chain phthalate esters (7). Also, floe and
emulsion formation was minimized, even for the continuous
extractor method. All compounds, except the most basic ones.
such as aniline or benzidine, are extracted at a pH <2.
In these experiments, sodium thiosulfate and sodium
arsenite were tested as dechlorinating agents. Chlorinated
(1.5 ppm total chlorine) samples spiked with.surrogate and
matrix spike compounds were analyzed. The extraction
procedure was similar to that listed under procedure A with
the following exceptions:
a. Chlorine concentrations were 1.5 ppm.
b. Surrogates and matrix spikes were spiked into
separate aliquots above the surface of the water.
c. 200 mL methylene chloride was added to the boiling
flask directly, instead of being poured through the
sample.
d. Samples were first extracted under acid conditions
(pH <2), followed by a basic extraction (pH >11).
e. Acenaphthene, not acenaphthylene, was used as a
matrix spike compound.
Part 2
In a similar experiment, L-ascorbic acid was tested as a
dechlorinating agent. The extraction procedure was similar
to that listed under procedure A with the following
exception: Samples were first extracted under acid conditions
(pH <2), followed by a basic extraction (pH >11).
C. Separators Funnel Extraction
EPA Method 625 (Base/Neutral. Acid Extraction)
Part 1
Sodium thiosulfate, sodium arsenite and L-ascorbic acid
10
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were tested as dechlorinating agents using Method 625 (1).
One exception to Method 625 should be noted: the base/neutral
and acid extracts were combined before concentration. The
initial chlorine concentration was 2.2 ppm for the sodium
arsenite and L-ascorbic acid extractions. The initial
chlorine concentration for the sodium thiosulfate extraction
was 1.3 ppm. 5 grams of each dechlorinating reagent (per
200 mLs of chlorinated sample) was used to reduce the
chlorine. Each was added to extreme excess to test for the
presence of interfering peaks.
Part 2
Method 625 (1) recommended the use of 80 mg of sodium
thiosulfate per liter of sample. 200 mLs of a 1.3 ppm total
chlorine aliquot was prepared and 160.9 mg of sodium
thiosulfate was added to neutralize the chlorine. The
extraction was performed as in EPA Method 625 (1), except
that base/neutral and acid extracts were combined before
analysis.
D. Recovery Of Nitrobenzene And 2.4-Dinitrotoluene From
Chlorinated Extracts Using L~Ascorbic Acid As A
Dechlorinating Agent
This experiment was performed to determine the
recoveries of nitrobenzene and 2,4-dinitrotoluene under
both acid/neutral and base/neutral conditions. The results
of procedures A and B indicated that 2,4-dinitrotoluene
was lost under base/neutral extraction conditions. It was
decided to also test a related compound, nitrobenzene, to
determine if a whole class of compounds (nitroaromatics)
were affected. All extractions were performed by the
continuous extraction method.
The following were extracted under base/neutral,
acid extraction conditions....
1. A one liter deionized water blank.
2. A one liter deionized water blank containing
1.25 g L-ascorbic acid.
3. One liter deionized water chlorinated to 0.9
ppm total chlorine, 1.25 g L-ascorbic acid
added as dechlorinating agent.
4. A duplicate of 3.
The following were extracted under acid/neutral
base extraction conditions.
5. One liter deionized water chlorinated to 0.9
ppm total chlorine, 1.25 g L^ascorbic acid
added as dechlorinating agent.
11
-------
6. A duplicate of 5.
All samples were spiked with 100 uL of a standard
containing 500 ug/mL each of nitrobenzene and 2,4-dinitro-
toluene. A reference was also prepared by adding 100 uL of
the standard to a 1 mL volumetric flask, and diluting to
volume with methylene chloride. Percent recovery of the
spike was determined by the following formula:
% Rec. •» na measured in extract X 100
ng measured in reference
E. Recovery Of 2.4-Dinitrotoluene and 2,6-Dinitrotoluene
From Chlorinated Extracts Using L~Ascorbic Acid As A
Dechlorinatinq Agent
This procedure was performed to determine the recoveries
of 2,4-dinitrotoluene and 2,6-dinitrotoluene under base/neutral
extraction conditions using both excess (3.3 g/L) and low
levels (80 mg/L) of L-ascorbic acid. 80 mg is the quantity
recommended by EPA Method 625 for sodium thiosulfate
addition. All extractions were performed by the continuous
extraction method.
The following were extracted:
1. One liter deionized water.
2. One liter deionized water blank chlorinated to
0.6 ppm total chlorine, 80 mg of L-ascorbic acid
added as dechlorinating agent.
3. A duplicate of 2.
4. One liter deionized water chlorinated to 0.6 ppm
total chlorine, 80 mg of L-ascorbic acid added
as a dechlorinating agent. (Analyzed in
quadruplicate).
5. One liter deionized water chlorinated to 0.6 ppm
total chlorine, 3.26 g of L-ascorbic acid added
as a dechlorinating agent.
Samples 1, 4 and 5 were spiked with 100 uL of each
of the following:
500 ug/mL 2,6-dinitrotbluene
Base/neutral matrix spike mix (containing
500 ug/mL 2,4-dinitrotoluene)
A reference was also prepared by adding 100 uL of each
standard to a 1 mL volumetric flask, and diluting to volume
with methylene chloride. Percent recovery of the spike was
determined by the following formula:
% Rec = nq measured in extract X 100
ng measured in reference
12
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F. Comparison Study Using 20 and 80 mo/L of Sodium Thiosulfate
As A Dechlorinatina Agent
This study was performed to compare the recommended
level of sodium thiosulfate (80 mg per liter of sample as
stated in Method 625) with a lower level, 20 mg/L. Both
levels were tested using continuous extraction. Separately
funnel extraction was used to test recoveries at the 80 mg
level only.
The following tests were performed:
1. Continuous extraction using 80 mg/L sodium
thiosulfate
2. Continuous extraction using 20 mg/L sodium
thiosulfate
3. Separately funnel extraction using 80 mg/L
sodium thiosulfate.
In each test, the following were analyzed:
1. A one liter deionized water aliquot spiked
with surrogate and matrix spike compounds
and extracted under acid/neutral, base
conditions.
2. A duplicate of 1.
3. A one liter deionized water aliquot spiked
with surrogate and matrix spike compounds
and extracted under base/neutral, acid
conditions.
4. A duplicate of 3.
The residual chlorine concentration was 1.6 ppm for the
80 mg/L tests and was 1.8 ppm for the continuous extraction
analysis using 20 mg/L sodium thiosulfate.
A reference was also prepared by adding 100 uL of each
standard to a 1 mL volumetric flask, and diluting to volume -
with methylene chloride. Percent recovery of the spike was
determined by the following formula:
% Rec = na measured in extract X 100
ng measured in reference
13
-------
VI. GENERAL QUALITY CONTROL
a. All glassware, sodium sulfate and glasswool used in
•this experiment was previously muffled at 450°C for
3-4 hours.
b. All surrogate, base/neutral and acid matrix spike
standards were, traceable to the Quality Assurance
Materials Bank in Research Triangle Park, N. C. The
internal standard mix was obtained from Supelco,
Beliefonte, Pa.
c. Each GC/MS was calibrated with FC43 prior to
analysis.
d. Each GC/MS was tuned by obtaining the spectrum of
DFTPP. All mass assignments and relative abundances
were found to be in acceptable ranges or the
instruments were adjusted until suitable spectra
were obtained.
e. Immediately before analysis, each sample was spiked
with an internal standard mixture, including
d^Q-phenanthrene. All guantitation was done using
d10-phenanthrene as the internal standard.
f. The sensitivity of each instrument to 40 ng of
d10-phenanthrene was as follows: ••••.-
Finnigan 4500 GC/MS : 80,000 area counts (average)
Finnigan 4023 GC/MS : 110,000 area counts (average)
g. All surrogate and matrix spike recovery limits
referenced in this study were from the Superfund
Contract Laboratory Program (CLP) protocols (8).
h. All recoveries were compared against a reference
standard prepared the same day the samples were
extracted. Reference standards and samples were
analyzed on the same day and on the same GC/MS.
i. Data guantitation was performed by automated
procedures using Incos software (Finnigan MAT, San
Jose, California).
j. Matrix spike and surrogate compound identifications
were made by comparing known reference spectra to
those of the unknowns. Other compound identifica-
tions, such as contaminant peaks associated with
certain L-ascorbic acid additions, were made using
the EPA-NIH spectral library.
14
-------
VII. EXPERIMENT-SPECIFIC QUALITY CONTROL
Procedure A Continuous Extraction EPA Method 625 (1)
(Base/Neutral, followed by Acid Extraction)
1. A deionized water blank was extracted along with the
samples. Two chlorination blanks were also
extracted (1000 mLs deionized water, chlorinated
using Chiorox, with no dechlorination agent added).
2. Each sample, except the deionized water blank, was
analyzed in duplicate.
3. Blanks and the reference standard were run on both
instruments. References were run at the start and
end of each day's analyses, except on one day when
only two analyses were performed. In this case, a
single reference was run between the two analyses.
Procedure B Continuous Extraction .
(Acid/Neutral, followed by Base Extraction)
1. .A deionized water blank was extracted. Two chlorin-
ation blanks were also extracted (one was spiked
with surrogates, the other with matrix spike
compounds).
2. L-ascorbic acid analyses were performed in
duplicate. All other tests represent a single
analysis.
3. Blanks and the reference standard were run on both
instruments. References were either run at the
start and end of each day's analyses, or a single
reference was run just prior to the sample
analyses.
Procedure C Separately Funnel Extraction
EPA Method 625 (1)
(Base/Neutral, followed by Acid Extraction)
1. A method blank was analyzed with each set of analyses.
Procedure D Recovery of Nitrobenzene and 2,4-Dinitrotoluene
From Chlorinated Extracts Using L-Ascorbic Acid
As A Dechlorinating Agent
1. A method blank was analyzed (base/neutral extraction).
2. A non-chlorinated blank containing L-ascorbic acid
was analyzed (base/neutral extraction).
15
-------
3. A reference was analyzed before the extracts.
4. All samples except blanks were analyzed in
duplicate.
Procedure E Recovery of 2,4-Dinitrotoluene and
2,6-Dinitrotoluene From Chlorinated
Extracts Using L-Ascorbic Acid As A
Dechlorinating Agent
1. A control containing no added chlorine or
L-ascorbic acid was spiked and analyzed.
2. Two chlorinated blanks containing 80 mg/L of
L-ascorbic acid were analyzed.
3. The analysis as described under number 4 of
procedure E was performed in quadruplicate.
4. A reference was analyzed before the extracts.
Procedure F Comparison Study Using 20 and 80 mg/L
of Sodium Thiosulfate As A Dechlor-
inating Agent
1. Each extraction was performed in duplicate.
2. A reference was analyzed along with the extracts.
16
-------
VIII. RESULTS AND DISCUSSION
Effects of Chlorination
The effects of Chlorination on the surrogate and matrix
spike compounds were determined. As shown in Table 1, the
recovery of de-phenol under base/neutral, acid extraction
conditions using the continuous extraction method was 8.45%.
This loss of d5-phenol was reflected in the observation of
the Chlorination product, d5-chlorophenol. ''
Similar results were encountered for the matrix spike
compounds. Extracting the matrix spike compounds in the
presence of chlorine fsamples 2 and 3 under base/neutral
conditions) caused reactions to occur which decreased the
concentration of phenol and 4-chlbro-3-methvlphenol. The
average recoveries for phenol and 4-chloro-3-methylphenol
were 9.4% and 33.65% respectively (Table 2). The products
formed by the Chlorination of these compounds were as
follows: 2,4-dichlorophenol; 2,6-dichlorophenol; 3-chlor-
ophenol; 2/4-dichloro-6-methylphenol; and 2-chlorophenol.
The effect of Chlorination would be expected to be
intensified under acidic extraction conditions (pH < 2),
since most of the chlorine would be in the free reactive
state (6). Under basic conditions, most of the chlorine
would be present as hypochlorite ion (6).
pH>4
C12 + H20 <=> HC1 + HOC1
2 2 PH<4
PH>9
HOC1 <=> IT" + OC1~
pH<9
Increased Chlorination products of the matrix spike
compounds were observed under acid/neutral conditions. These
included: 2,4-dichlorophenol; 3-chlorophenol; 2,6-dichloro-
phenol; 1,2,3-trichlorobenzene; 2,4-dichloro-6-methylphenol;
3,4,6-trichloro-o-cresol; 2-chlorophenol; chloroacenaphthene;
dichloroacenaphthene and chloropyrene. (It should be noted
that the matrix spike mix used for the acid/neutral
extraction included acenaphthene instead of acenaphthylene).
Matrix spike recoveries for acid/neutral extraction are
given in Table 4. It should be noted that phenol, 4-chloro-
3-methylphenol, acenaphthene and pyrene showed significant
recovery losses under these conditions. The recovery of the
surrogate d5-phenol was only 0.7% (Table 3).
17
-------
TABLE 1
EXPERIMENT A: CONTINUOUS EITRACTION (BASE/NEUTRAL, ACID)
SURRD6ATE SPIKE RECOVERY
REPORTED AS I)
COMPOUND
2-FLUORDPHENDL
W-PHENOL
OS-NITROBENZENE
2-FLUORO-l,l'-BIPHENYL
2,4,6-TRIBROHOPHENOL
D14-P-TERPHENYL
EITRACTS
CHLORINATED SODIUM
BLANK EXTRACT THIOSULFATE
71.4
77.8
B7.1
87.5
81.8
68.1
45.2
8.45
76.5
61.65
72.95
84.9
51.7
59.5
61
53.2
66
69.35
SODIUM L-ASCORBIC
ARSEHITE ACID
70.05
77.05
60.05
64.05
85.25
91.9
60.35
85.35
87.65
74.2
93.25
97.05
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
BLANK RESULTS REPRESENT ONE ANALYSIS.
ALL OTHER RESULTS ARE AVERAGES OF DUPLICATE ANALYSES.
18
-------
TABLE 2
COHPOUND
EIPERIflENT A: COHTINUOUS EITRACTION (BASE/NEUTRAL, ACID)
DATRII SPIKE RECOVERY
(REPORTED AS I)
EXTRACT ,
CHLORINATED SODIUM SODIUN L-ASCORBIC CLP LIMITS
BLANK EXTRACT THIOSULFATE ARSENITE ACID (HATER)
PHENOL
2-CHLDROPHENOL
1,4-DICHLOROBENZENE
N-NITROSODI-N-PROPYLAHINE
1,2,4-TRJCHLOROBENJENE
4-CHLORO-3-UETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
84.7
87.9
90.7
92.9
90.6
91.6
99.1
71.2
93.5
61.1
21.6
92.1
9.4
105.7
75.6
76.8
81. 1
33.65
87.8
66.75
79.65
55.65
34.7
82.65
61.1
62.55
63.95
66.35
66.25
68.15
72.65
70.2
71.4
64.65
30.95
.69.6
80
79.95
84.05
85.8
64.15
85.7
91.5
85.05
90.3
80.85
50.65
91.35
87.9
79.85
88.2
91.55
86.35
92.15
89.9
97.25
60.75
106.5
57.95
95.05
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
BLANK RESULTS REPRESENT ONE ANALYSIS.
ALL OTHER RESULTS ARE AVERAGES OF DUPLICATE ANALYSES.
19
-------
TABLE 3
EXPERIHENT B: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
EXTRACTS
CHLORINATED SODIUH SODIUM L-ASCORBIC CLP LIMITS
COHPDUND BLANK EITRACT ARSENITE THIOSULFATE ACID (HATER)
2-FLUORDPHENDL 93.2 52.4 68.7 55.7 79.B 21-100
D5-PHENOL 83.9 0.7 55.9 46.8 81.1 10-94
D5-NITRDBENZENE 92 85 79.6 62.9 84.7 35-114
2-FLUORO-l,r-BIPHENYL 90.7 84.4 81.5 67.9 72.5 43-116
2,4,6-TRlBRONOPHENOL 90.5 69.3 69.3 53.5 . 84 10-123
D14-P-TERPHENYL 97.6 87.2 88.9 75.9 86.5 33-141
RESULTS FOR L-ASCORBIC ACID ARE AVERAGES OF DUPLICATE ANALYSES.
ALL OTHER RESULTS REPRESENT ONE ANALYSIS.
20
-------
Our laboratory currently uses methylene chloride that
contains cyclohexene as a preservative. The purpose of this
additive is to scavenge any HC1 present in the solvent. This
additive has been detected in samples and blanks, along with
the following related compounds: cyclohexanone; 2-cyclohexen-
1-one; and 2-cyclohexen-l-ol. Extracted samples that con-
tained chlorine have produced the following derivatives of
cyclohexene: chlorocyclohexene; dichlorocyclohexane; chloro-
cyclohexanone; and 3,3,3-trichloro-l-propene.
Sodium Thiosulfate
Sodium thiosulfate, sodium arsenite and L-ascorbic acid
were tested to determine their suitability as dechlorinating
agents. Sodium thiosulfate, the compound required by Method
625 (1) for dechlorinating waste effluents, was the least
suitable reagent tested when excess amounts were used. It is
stated in this method that sodium thiosulfate is to be added
in the field. Field conditions are difficult to control and
it is conceivable that excess amounts could be added. Method
625 (1) specified that 80 mg of sodium thiosulfate per liter
of sample should be added to neutralize the chlorine. No
analytical problems were encountered when this amount was
used for separatorv funnel extraction. However, a signif-
icant molecular sulfur peak was obtained using 80 mg of
sodium thiosulfate per liter of sample under continuous
extraction conditions. It should be emphasized that all
observations concerning the testing of the three dechlor-
inating agents were made when excess amounts of each
were used.
With the exception of 2,4-dinitrotoluene, recoveries of
matrix and surrogate spike compounds were lowest for those
samples dechlorinated with sodium thiosulfate (Tables 1 and
2). These lower recoveries may be due to the large number of
sulfur crystals which formed in the concentrator tube during
the Kuderna-Danish process. It is possible that matrix and
surrogate spike compounds became trapped in the sulfur
crystals, resulting in lower recoveries.
Chromatographic problems were also encountered with
sodium thiosulfate. A large molecular sulfur peak eluted at
1500-1850 scans (RRT of 0.990 - 1.145, relative to
d10-phenanthrene). Figure 2 shows the large sulfur peak
formed as a result of using an excess (5 g) amount of sodium
thiosulfate for dechlorination (upper chromatogram). When
160 mg was used (lower chromatogram), the sulfur peak was
still detected, but at a level that would not cause any
analytical problems. The six sharp peaks appearing in both
chromatograms in figure 2 are internal standards. The dual
chromatogram comparison contrasts the effect of excess sodium
-------
Figure 2
RIC
85/19/88 18:88:88
SAMPLE:,
RANGE: C 1^4588 LABEL: H 8/4.8 BASE: U 28, 3
DATA: THI01 *1,168MGTHIO
CALI: CAL8282 «1
CM
c\j
. RIC
92544
Experiment C:
Separatory Funnel Extraction
Using 5 g of Sodium Thiosulfate
83.1
. RIC*
7b328
Experiment C:
Separatory Funnel Extraction
Using 160 mg of Sodium Thiosulfate
i
568
6:48
1088
13:28
—I—
1588
28;88
2000
26:48
2500
33:28
SCAN
TINE
-------
thiosulfate with an amount near the recommended level (80
mg). The molecular sulfur peak (formed when excess amounts
of sodium thiosulfate are used) co-elutes with the following
compounds: bromophenoxybenzene, hexachlorobenzene, penta-
chlorophenol, d^p-phenanthrene (internal standard),
phenanthrene, anthracene, di-n-butyl phthalate and fluor-
anthene. However, quantitation was not affected since no
interference was observed with the quantitation ions (base
peaks) used for each compound. Identification of the above
listed compounds would have to be made by subtracting the
molecular sulfur spectrum (Figure 2A) from the total
spectrum. Another interferent, hexathiepane, had a relative
retention time of 0.975. It did not co-elute or interfere
with the analysis of any semi-volatile compound listed under
EPA Method 625 (1).
The problems cited above with the use of sodium thio-
sulfate occurred as a result of the acidic extraction of the
test samples. Under acidic conditions, sodium thiosulfate is
unstable and undergoes the following decomposition and
disproportionation reactions (2) :
1. S203-2 —> S(s) + S03-2
Decomposition/disproportionation of thiosulfate to
sulfur and sulfite ion.
2. 2S903~2 —> S/-N + 3SO? + 4e-
ft J \^ / *
Decomposition/disproportionation of thiosulfate to
sulfur and sulfur dioxide (2,9).
Equation 2 probably represents the S02 source which is
reported to cause interferences with GC/MS analysis using
purge and trap (excess sodium thiosulfate under acidic
conditions) (4).
Under acidic conditions, a colloidal solution of sulfur
is stabilized by the acid (9). Reactions 1 and 2 do not
occur under slightly acidic, neutral or basic conditions.
Thiosulfate is stable under these conditions, and forms the
tetrathionate ion (2):
2S203~2 —> S406~2 + 2e-
The sulfur detected by GC/MS analysis and observed in
this work is molecular sulfur (S8). After elemental sulfur
has been formed as a result of acid extraction, a polymer-
ization reaction occurs to .form the S8 molecule. The
structure of this molecule is known as a "puckered ring" (2).
Sodium thiosulfate reduces chlorine according to the fol-
lowing equation (9) :
23
-------
Figure 2A
CSJ
LIBRARY SEARCH
84/11/88 14:29:88 + 23:47
SAMPLES OECHLOR
CONOS.t 38C 2 HIM TO 388C AT 18/WN
EWftNCEO (S 156 2N 8T)
DATA: DCB5811 11784
CALIs CAL1217B I 2
BASE H/E: 64
RICi 6783.
1608 1
SAMPLE
r
l 1. ' 1 1 ll 1. . - ll
Sample Spectrum
58
H MT1
B PK
RfiMK,
PUR ^938
SULFUR, ML. (S8)
< I'. .
L
L
NBS Library Spectrum
-------
Na2S203 + H20 + C12 » Na2S04 + S + 2HC1
Elemental sulfur is produced as a result of the reduc-
tion of chlorine by sodium thiosulfate. The amount of sulfur
produced would be directly proportional to the amount of
chlorine. In this work, chlorine concentrations of between
0.6 and 2.2 ppm were used. Thus, the amount of sulfur
produced as a result of this reaction would also be in this
range. However, most of the sulfur that caused chromato-
graphic problems in these experiments was formed under acidic
extraction conditions as detailed above (decomposition/dis-
proportionation reactions). This resulted from the addition
of excess sodium thiosulfate in gram quantities.
The continuous extraction acid/neutral, base extraction
scheme gave greater recoveries than for base/neutral, acid
extraction for all matrix spike compounds except 4-nitro-
phenol (Tables 2 and 4). Surrogate recoveries (Tables 1 and
3) did not exhibit any general trend toward favoring one or
the other. All raw data for sodium thiosulfate can be found
in Tables 2A and 6A in the Appendix.
Sodium Arsenite
Sodium arsenite produced the cleanest chromatogram of
the three compounds tested. Figure 3 (upper chromatogram)
showed the result when an excess (5 g) of sodium arsenite was
used as the dechlorinating reagent (separatory funnel
extraction). A small unknown peak eluting just before the
third internal standard, d10-acenaphthene, was too small to
be quantitated by the Incos software. Figure 4 compared the
two dechlorinating reagents, sodium thiosulfate and sodium
arsenite, in a dual chromatogram display. In each case,
excess amounts were used (2.5 g, continuous extraction). The
molecular sulfur peak was prominent in the sodium thiosulfate
chromatogram; the interference peak mentioned above for
sodium arsenite was a very small peak, just above the
detection level, and not appearing in the lower chromatogram.
The sharp peaks that appeared in the chromatograms were
internal standards, surrogates and matrix spike compounds.
Sodium arsenite gave acceptable results for all spike
components (Tables 1 and 2). The percent recovery for di-n-
butyl phthalate was low: 50.65% using continuous extraction
under base/neutral, acid extraction conditions. However,
recoveries for all three dechlorinating agents were low for
this compound under these conditions. This is due to the
fact that certain phthalates hydrolyze under basic condi-
tions (7). With the exception of di-n-butyl phthalate, all
other compounds gave similar recoveries when the two ex-
traction schemes were compared for the continuous extraction
method (sodium arsenite dechlorination). Results for
acid/neutral extraction are shown in Tables 3 and 4. The raw
data for sodium arsenite may be found in Tables 3A and 7A in
25
-------
R1C OAT
•VI2/ti 9i23:M CM.
OKS.I 3K 2 MM TO 3WC *f 1«/1U»
MNCti & l.ZM IMBJ M 1. 4.e Oi
iM.I
•
. me
A
see teee
taAXSEHITCM SCA« 334 TO 27» FiaUTP 3
ItCDLUlTItt OUT OF 391 TO 27M riyu.eo
Mkft t. |.tJ • Mfibltat. 9
49*24.
Experiment C:
Separatory Funnel
Extraction Using 5 g
of Sodium Arsenite
•
T1IC
•1C
•M?iM
COC5.I 3K 2MINTO
WKCl 6 1.33H
DAT* ASCCniC It
O«.h CAU217I 12
•T IMIIN
N t. 4.«
*•.!.• J •
rlM.I
RIC
see
tew
391 TO 27W
OUT OF 3MT027M
Experiment C:
Separatory Funnel Extraction
Using 5 g of L-Ascorbic Acid
26
-------
180.
RIC
42.9-
RIC1
Figure 4
RIC
64/11/88 12:40:88
SAMPLE: DECHLOR
CONOS.i 30C 2 HIM TO 386C AT 18/MIM
RANGES G 1*3388 LABai N 0* 4.8 BASE: U 20, 3
CVJ
DATA: DCB4011 ILDCB69H
CALI: CAL1217B «2
SCANS 350 TO 2706
i 1
135424.
Experiment A:
Continuous Extraction
(Base/Neutral, Acid Extraction)
Using Approximately 2.5 g of
Sodium Thiosulfate
11.
• 1
500
I |
I •
Experiment A:
1
1
Continuous Extraction
(Base/Neutral, Acid Extraction)
Using Approximately 2.5 g of
Sodiun
i Arsenite
i I i i i i I • • • i i
• •
1000 1500 2000 2500
6; 40 i3i2B SHsflO 26:40 33)20
58048.
SCAN
TIME
-------
TABLE 4
COMPOUND
EXPERIMENT B: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
HATRII SPIKE RECOVERY
(REPORTED AS I)
EXTRACT
CHLORINATED SOD1UN SODIUH L-ASCORBIC
BLANK EXTRACT THIOSULFATE ARSENITE ACID
CLP LIMITS
(HATER)
PHENOL
2-CHLOROPHENOL
1,4-DICHLOROBENZENE
N-NITROSQDI-N-PROPYLANINE
1,2,4-TRICHLORDSENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE/ACENAPHTHENE
4-NITROPHENOL
2,4-DINITRDTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALftTE
PYRENE
99.6
100
94
102
92
102
9B
94
103
80
101
103
9.9
107
62.3
85. &
86
19.4
13.8
68.7
96.4
133
98.6
40.8
78.1
76.7
65.6
78.9
69.3
75.8
79
69.2
77.8
94.5
95.7
85.9
86.9
86.5
81
86.6
63.6
85
BB.l
80.2
85.4
94.3
92.2
BB.2
86. 5
86.1
86.7
90.3
87
88. 6
89.1
8B.9
91
94.5
92
92.3
12-89
27-123
36-97
41-116
39-98
23-97
46-1 IB
10-80
24-96
9-103
11-117
26-127
RESULTS FOR L-ASCORBIC ACID ARE AVERAGES OF DUPLICATE ANALYSES.
ALL OTHER RESULTS REPRESENT ONE ANALYSIS.
oo
-------
the Appendix.
Sodium arsenite (Na3As03 or NaAs02) is a white/ water-
soluble powder. It reduces chlorine according to the
following equation (9):
AsO3~3 + C12 + H2O'- As04~3 + 2HC1
Arsenite Arsenate
This reaction does not proceed under strongly acidic
conditions, since the arsenite would then be converted to
arsenious acid, a non-reducing agent (9).
No analytical or chromatographic problems were
encountered with sodium arsenite. It is, however, very
toxic. The probable oral lethal dose for humans is less
than 5 mg/kg (3).
L—Ascorbic Acid
L-ascorbic acid gave the highest recoveries for the
surrogate spike compounds and for most of the matrix spike
compounds except 2-chlorophenol, acenaphthylene and 2,4-
dinitrotoluene (Tables 1 and 2, continuous extraction,
base/neutral, acid extraction conditions). Chromatographic
interferences were observed at relative retention times of
0.307, 0.453, 0.509, 0.527 and 0.606, relative to d10-
phenanthrene. These five peaks corresponded to the following
compounds respectively: 2-furancarboxaldehyde, C5H4Oo, CAS
No. 98-01-1; an unidentified compound, with base peak of m/z
55; 2-furancarboxylic acid, C5H4O3, CAS No. 88-14-2;
3-furancarboxylic acid, methyl ester, C6H603, CAS No.
13129-23-2; and 4H-pyran-4-one, 3,5-dihydroxy-2-methyl,
C6H6°4» CAS No> 1073-96-7. 2-furancarboxylic acid would
interfere with the quantitation of bis(2-chloroisopropyl)
ether. The quantitation ion, 45, was present in the spectrum
of 2-furancarboxylic acid. For other peaks eluting at this
time (benzenemethanol, 2-methylphenol and 4-methylphenol),
quantitation was not affected. 2-furancarboxaldehyde and
3-furancarboxylic acid, methyl ester did not interfere in the
analysis of semivolatiles. 4H-pyran-4-one, 3,5-dihydroxy-2-
methyl eluted near 1,2,4-trichlorobenzene, but did not
interfere with quantitation. The unknown peak eluted near
2-chlorophenol, but did not interfere with quantitation.
These interferences are observed in Figure 5 in the
upper chromatogram. The lower chromatogram provides a
comparison with sodium arsenite. The major difference was
the large interference peak at scan 748 (RRT = .453) in the
L-ascorbic chromatogram. This peak could not be identified.
Figure 3 (lower chromatogram) showed the chromatogram re-
-------
RIC DATA: DCB8 tl,DCB7
84/11/88 18(18:88 CALI: CAL8282 fl
SAMPLE:
RANGE: G 1,3588 LABEL: N 8/4.8 BASE: U 28, 3
748
SCANS 388 TO 1888
o
CO
tw.u-
RIC.
—
1 Experiment A:
ft Continuous Extraction
233376
II (Base/Neutral, Acid Extraction)
j Using Approximately 2.5 g of
s
i| L-Ascorbic Acid
717 |
378
329 |L
^ i
53.7-
RIC|
^ \ • i • i
776
7 "?
III
11(1 All » 377
1 j 1 I 1
715
Experiment A:
Continuous Extraction
1
157448
| 73ft (Base/Neutral, Acid Extraction)
'
• |
563
49 | . [
375
1 «
1
II
1 i
300 400
* 540
V_ 473 JV l\5§4 626 m 686 |
\ | i | J^ |
500 609 700
L^,
Using Approximately 2.5 g of
Sodium Arsenite
773 849
.
.
800
873 1
1
A
1
1
11
Jl_ 938 9A4 1
• | i | i
. '
800 900 1000 SCAN
4:00 5:20 6:40 8:00 9:20 16:40 12:60 13:28 TINE
-------
suiting when an excess amount (5 g) of L-ascorbic acid is
added and extracted using a separatory funnel. No inter-
ference peaks were observed, as they were when continuous
extraction was employed. Continuous extraction gave
better recoveries for all compounds (Tables 1 and 2),
including interference peaks.
The reduction of chlorine by L-ascorbic acid is
represented by the following equation (10):
C6H8°6 + C12 = C6H6°6 + 2HC1
L-ascorbic acid L-dehydro-
ascorbic acid
Under basic conditions, L-dehydroascorbic acid is
converted to L-diketogulonic acid (C6H807) (11).
Using the continuous extraction method under
base/neutral extraction conditions, recoveries of 2,4-di-
nitrotoluene from a matrix spike were much lower (60.75%)
than for any other agent or blank tested (Table 2). In a
similar experiment (procedure D, spiking with nitrobenzene
and 2,4-dinitrotoluene), an average recovery of 30.1% was
obtained for 2,4-dinitrotoluene (Table 5). The recovery was
probably lower due to the larger amount of L-ascorbic used
(5 g as compared to 2.5 g in procedure A).
In procedure E, the recoveries of 2,4-dinitrotoluene and
2,6-dinitrotoluene were determined under base/neutral, acid
extraction conditions, using both excess and low (80 mg per
liter of sample, the recommended level of sodium thiosulfate
as specified in Method 625) levels of L-ascorbic acid.
Results are reported in Table 6. When 8.0 mg of L-ascorbic
acid per liter of sample was used as the dechlorinating
agent, good recoveries of both compounds were obtained.
Recoveries were similar to those of a spiked control blank.
However, when excess amounts (3.3 g/L) of L-ascorbic acid
were used for dechlorination, recoveries for both compounds
were lower as compared to the control. The recovery of 2,4-
dinitrotoluene was 41%; 2,6-dinitrotoluene was recovered at
80.4% (as opposed to recoveries of 96.6 and 93.5 respectively
for the control). Under acid/neutral extraction conditions
using a continuous extractor and approximately 2.5 g of L-
ascorbic acid, the average recovery of 2,4-dinitrotoluene was
91% (Table 4). Raw data for L-ascorbic acid may be found in
Tables 4A, 4B, 8A, 8B, 9A and 10A in the Appendix.
It may be possible that L-diketogulonic acid (the form
of L-ascorbic acid under basic conditions) reacted with 2,4-
dinitrotoluene. However, no reaction products were detected.
It has been found that o-nitrotoluene reacts with galactose,
fructose or mannose under basic conditions at a temperature
of 80-90°C to form 2,2'-dimethylazoxybenzene (Cj^^o1^0)
(12). Possibly, 2,4-dinitrotoluene could have been converted
31
-------
TABLE 5
EXPERIMENT D: CONTINUOUS EXTRACTION
AROHATIC MITRO COMPOUND RECOVERY .
(REPORTED AS 1)
DECHLORINATION USINB 1.25 6 L-ASCORBIC ACID
CONFOUND
2,4-DINITRDTDLUENE
NITROBENZENE
BLANK
94
103.5
EXTRACTS
BLANK + BASE/NEUTRAL ACID/NEUTRAL CLP LIHITS
ASCORBIC ACID (AVERAGE) (AVERAEE) (HATER)
33.9
106.1
30.1
98.5
96.7
105.7
24-96
NA!
BLANKS HERE NOT CHLORINATED
BLANKS HERE EXTRACTED UNDER BASE/NEUTRAL CONDITIONS
B/N AND A/N EXTRACTS HERE CHLORINATED TO 0.9 PPH TOTAL CHLORINE
00
-------
TABLE 6
EXPERIMENT E: CONTINUOUS EXTRACTION
BASE/NEUTRAL, ACID EITRACT10N
BINITROTOLUENE RECOVERY
(REPORTED AS Z)
OECHLORINATION USING L-ASCORBIC ACID
COMPOUND
2,4-DJNITROTOLUENE
2,6-DINITROTOLUENE
BLANK
94.6
93.5
EXTRACTS
3.3 6/L 80 NB/L
L-ASCORBIC ACID L-ASCORBIC ACID CLP UNITS
(SIN6LE VALUE) (AVERAGE) (NATER)
41
80.4
91.B
90.1
24-96
NAt
BLANK MAS NOT CHLORINATED
ALL OTHER SAMPLES HERE CHLORINATED, TO 0.6 PPH TOTAL CHLORINE
t NO LIMITS AVAILABLE
-------
to its corresponding azoxy compound (general form:
ArN(0)=NAr) (13).
Summary of Results
Table 7 provides a summary of observations which
compares the three dechlbrinating agents when excess
amounts of each are used.
34
-------
TABLE 7
SUMMARY OF OBSERVATIONS
CONSEQUENCES OF ADDITION OF EXCESS DECHLORINATING AGENT
DECHLOR-
INATION
AGENT
SODIUM
THIOSULFATE
CONTINUOUS EXTRACTION
SODIUM
ARSENITE
L-ASCORBIC
ACID
EFFECTS OF
CHLORINATION
(NO DECHLOR-
INATION)
Base/Neutral.
Acid Extraction
Sulfur
crystal
formation.
Acceptable
but reduced
recoveries
for matrix
spikes &
surrogates.
Low di-n-
butyl
phthalate
recovery.
Acceptable
recoveries
for all
matrix spike
and surrogate
compounds.
Low di-n-
butyl
phthalate
recovery.
No interfer-
ence peaks.
Acceptable
recoveries
for all
cmpds. Low
recoveries for
2,4-dinitrotoluene
& di-n-butyl
phthalate.
Five interference
peaks observed.
Low recoveries
of d5-phenol;
phenol; 4-chloro-
3-methylphenol &
di-n-butyl
phthalate.
Chlorination
products formed.
Acid/Neutral.
Base Extraction
SEPARATORY FUNNEL EXTRACTION
Base/Neutral,
Acid Extraction
Sulfur
crystal
formation.
Acceptable
but generally
reduced
recoveries
for matrix
spikes &
surrogates
when compared
to sodium
arsenite &
L-ascorbic acid.
Acceptable
recoveries
for all
matrix spike
and surrogate
compounds.
No interference
peaks.
Sulfur
crystal
formation.
(No recovery
data available)
One small
peak
observed,
but did
not interfere.
(No recovery
data available)
Good
recoveries
for all
matrix spike
and surrogate
compounds.
Two inter-
ference peaks
observed.
Low recoveries of
d5-phenol;
4-chloro-3-methyl
phenol; acenaphthene
pyrene and phenol.
Chlorination
products formed.
No interference
peaks observed.
(No recovery
data available),
Not analyzed.
(No recovery
data available).
-------
Further Study of Sodium Thiosulfate
Method 625 recommends that 80 mg sodium thiosulfate per
liter of sample be used as a dechlorinating agent. This
amount presented a chroma tographic problem when continuous
extraction was performed (using either extraction sequence) .
Figure 6 showed the large molecular sulfur peak that eluted
over a broad range (over 300 scans) and had a peak maximum at
scan 1865. In contrast, Figure 7 showed the result when
20 mg of sodium thiosulfate per liter of sample was used.
There is no apparent molecular sulfur peak, but a very small
amount of sulfur was detected (peak maximum at scan 1876,
barely detectable on the chromatogram) .
The method of extraction greatly affected the amount of
molecular sulfur recovered. Figure 8 contrasted continuous
extraction with separatory funnel extraction when 80 mg/L of
sodium thiosulfate was used. The upper chromatogram showed
the large molecular sulfur peak obtained when continuous
extraction was employed. In contrast, the lower chromatogram
(separatory funnel extraction) indicated that no detectable
sulfur was extracted by this method. Both chromatograms
represent base/neutral, acid extraction schemes. Similar
results were obtained for acid/neutral, base extractions.
Matrix and surrogate spike recoveries were acceptable
for all analyses performed. Excellent recoveries were obtained by
the continuous extraction method using either 80 mg/L
sodium thiosulfate (Tables 8 and 9) or 20 mg/L (Tables 10
and 11) . The separatory funnel extraction method gave
significantly lower recoveries for certain phenolic
compounds: 2-fluorophenol; d5~phenol; phenol and 4-nitro-
phenol (Tables 12 and 13). This is due to more efficient
extraction of hydrophilic compounds when continuous
extraction is employed (7) . However, it did give a greater
recovery for di-butyl-phthalate when the extraction was
carried out under base/neutral, acid extraction conditions.
This compound hydrolyzes to a greater degree under continuous
extraction conditions (7) . All raw data for surrogate and
spike recoveries is shown in Tables 11A through 22A in the
Appendix.
As previously noted, sodium thiosulfate reduces chlorine
according to the following equation (9) :
-, + H?0 + Cl-> - Na5SOA + S + 2HC1
? * f71 al 2 4
flB o
mole mole
One mole of sodium thiosulfate reduces one mole of chlorine.
Stoichiometrically, the amount of sodium thiosulfate required
is about twice as much as chlorine. It was found in this study
that 20 mg of sodium thiosulfate reduced 10.5 mg of chlorine.
The use of 20 mg of sodium thiosulfate should be sufficient
36
-------
100.0
Figure 6
RIC DATA: DC2 #2732 SCANS
11/01/88 12:47:00 CALI: C4 #1 OUT OF
SAMPLE:
CONOS.: 30C 2 MIN TO 300 AT 10C/MIN
RANGE: G 1,2800 LABEL: N 0/4.0 QUAN: A 0, 1.8 J 0 BASE: U 20, 3
1001
1300 TO 2300
300 TO 2800
1391
1361
1438
1504
1811
Experiment F:
Continuous Extraction
Using 80 mg/L of
Sodium Thiosulfate
1687
1661
2011
1865
2238
1981
2175
r
1400
18:40
—I
1600
21:20
24:00
1
2000
26:40
2200
29:20
-------
Figure 7
00
1500 TO 2508
our OF see TO 2700
RIC DATA: OC2 *2394
10/17/88 10:03:00 CALI: CALJ2J7B
SAMPLE: DFCHLGR STUDY
COHDS.: 36C 2 HIM TO 300C AT IfiHUtf
RANGE: G 1,2700 LABEL: H 0, 4.0 QJAH: A 6. 1,0 J 8 BASE: U 20, 3
Experiment F:
Continuous Extraction
Using 20 mg/L of
Sodium Thiosulfate
1555
16S3
1532
1870
!835
1731
1738
2395
2213 2273
2363
IbOB
21:28
1806
24:00
2600
26:40
2206
29:20
I
2466
32:00
-------
100.0-1
RIC
98.4-1
RIC*
CALI: C4 fl,C4
RIC
11/01/88 13:51:00
SAMPLE:
CQNDS.: 30C 2 MIN TO 300 AT 10C/MIN
RANGE: G 1,2800 LABEL: N 0* 4.0 BASE: U 28, 3
Figure 8
DATA: DC3 #1,SF3
Oi
CO
L
IU
SCANS 300 TO 2800
235520.
Experiment F:
Continuous Extraction
Using 80 mg/L of
Sodium Thiosulfate
JL
231680.
J
Experiment F:
Separatory Funnel Extraction
Using 80 mg/L of
Sodium Thiosulfate
JL
500
K-40
13:20
1508
20:60
2000
26:40
2500
33:20
SCAN
TIME
-------
TABLE B
EXPERIMENT F: CONTINUOUS EXTRACTION
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING BO H6/L SODIUM THIDSULFATE
SAMPLE EXTRACT
A/N B/N CLP LIMITS
COMPOUND (AVE) (AVE) (HATER)
2-FLUOROPHENDL 87 81.7 21-100
D5-PHENOL 92.4 87.1 10-94
D5-NITR08ENZENE 90.9 63.1 35-114
2-FLUORO-l,l'-BIPHENYL 68.B B2.7 43-116
2,4,6-TRIBRDHQPHENOL 89 89.7 10-123
D14-P-TERPHENYL 89.7 B4.4 33-141
EXTRACTS CHLORINATED TO 1.6 PPM TOTAL CHLORINE
-------
TABLE 9
EXPERIMENT F: CONTINUOUS EXTRACTION^
MATRIX SPIKE RECOVERY
(REPORTED AS I)
HECHLORINAT10N US1HB 80 HE/L SODIUM THIOSULFATE
COHPOUND
PHENOL
2-CHLOROPHENOL
1,4-DICHLOROBENZENE
N-NITRDSOD1-N-PROPYLAHINE
1,2,4-TRICHLDROBENZENE
4-CHLORQ-3-HETHYLPHENDL
ACENAPHTHYLENE
4-N1TROPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENDL
DIBUTYLPHTHALATE
PYRENE
A/N
(AVE)
B/N
(AVE)
CLP LIHITS
(NATER)
93.1
90.2
84.7
106.9
66.6
97.2
86.3
101.8
94.2
112.2
97.7
91.6
85.1
85.9
77.9
90.9
78. B
86.8
80.3
96.3
B3.5
110.9
59.7
B5.3
12-89
27-123
36-97
41-116
39-98
23-97
46-1 IB
10-fiO
24-96
9-103
11-117
26-127
CHLORINATED TO 1.6 PPH TOTAL CHLORINE
41
-------
TABLE 10
EIPERIHENT F: CONTIHUOUS EXTRACTION
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING 20 HB/L SODIUM THIOSULFATE
COMPOUND
2-FLUOROPHENOL
D5-PHENOL
D5-NITROBENZENE
2-FLUORO-l,r-BIPHEHYL
2,4,6-TRIBROHDPHENDL
D14-P-TERPHENYL
A/N
(AVE)
94.3
93.1
92.6
98.2
95.1
93
SAMPLE EXTRACT
B/N
(AVE)
CLP LIHITS
(HATER)
80.7
83.7
93.8
91.1
82.7
91.5
21-100
10-94
35-114
43-116
10-123
33-141
EXTRACTS CHLORINATED TO l.B PPM TOTAL CHLORINE
42
-------
TABLE 11
EIPERIHENT F: CONTINUOUS EITRACTION
IUTRII SPIKE RECOVERY.
(REPORTED AS I)
DECHLORINATION USINB 20 HB/L SODIUM THIOSULFATE
COHPOUND
PHENOL
2-CHLDROPHENOL
1,4-DlCHLDROBENZENE
N-NITROSDDI-N-PRDPYLAH1KE
1,2,4-TRlCHLOROBENZENE
4-CHLORO-3H1ETHYLPHENOL
ACENAPHTHYLENE
4-NITRDPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
HBUTYLPHTHALATE
PYRENE
A/N
(AVE)
B/N
(AVE)
CLP LIMITS
(HATER)
93.9
95.6
90.75
83.25
98. 4
91.8
93.4
84. i
94.9
91.8
92.95
89.95
84.05
83.1
85.15
86.35
89.55
89.45
89.55
82
93.55
78.85
65.25
90.85
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
CHLORINATED TO 1.8 PPH TOTAL CHLORINE
43
-------
TABLE 12
EXPERIMENT F: SEPARATORY FUNNEL EITRACTIDN
SURROGATE SPIKE RECOVERY
(REPORTED AS Z)
DECHLORINATION USINB 60 HB/L SODIUH TH10SULFATE
COMPOUND
2-FLUOROPHENDL
D5-PHENDL
D5-NITROBENZENE
2-FLUORO-l,r-BIPHENYL
2,4,6-TRIBRONOPHENDL
D14-P-TERPHENYL
A/N
(AVE)
55.3
35.5
94.5
89.3
92.9
95.3
SAMPLE EXTRACT
B/N
(AVE)
50.2
32.7
86.2
76.9
81.6
92.1
CLP LIHITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
EXTRACTS CHLORINATED TO 1.6 PPH TOTAL CHLORINE
44
-------
TABLE 13
EXPERIMENT F: SEPARATORY FUNNEL EXTRACTION
MATRIX SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATIDN USIN6 80 H6/L SODIUM THIOSULFATE
COMPOUND
PHENOL
2-CHLOROPHENOL
1,4-DlCHLOROBENZENE
&-N1TRDSODI-N-PRDPYLAHJNE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-METHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
.2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
A/N
(AVE)
B/N
(AVE)
CLP LIMITS
(HATER)
37.1
68. 9
65. B
97.5
69.3
92.6
84.2
iB.6
86.7
87.5
90.1
87.4
34.4
80.3
61.4
100.9
63.8
82.5
86.1
14.6
90
6B.9
80.2
89.9
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
CHLORINATED TO 1.6 PPM TOTAL CHLORINE
45
-------
to neutralize the residual chlorine concentration of most
effluents encountered in NPDES sampling.
Table 14 is a summary of the results obtained by further
study of sodium thiosulfate.
-------
TABLE 14
SUMMARY OF OBSERVATIONS
DECHLORINATION USING SODIUM THIOSULFATE
TYPE OF
EXTRACTION
CONCENTRATION OF SODIUM THIOSULFATE
80 MG/L 20 MG/L
Continuous
extraction
(Acid/neutral,
base).
Excellent
recoveries
for all
matrix spikes
& surrogates.
Chromatographic
interference of
molecular sulfur.
Excellent
recoveries
for all
matrix spikes
& surrogates.
No chromatographic
interference due
to molecular
sulfur.
Continuous
extraction
(Base/neutral,
acid).
Good but
reduced recoveries
for all matrix
spikes &
surrogates.
Di-n-butyl
phthalate
recovery
about 60%.
Chromatographic
interference of
molecular sulfur.
Good but generally
reduced recoveries
for all matrix
spikes &
surrogates.
Di-n-butyl
phthalate
recovery
about 65%.
No Chromatographic
interference due
to molecular
sulfur.
Separatory
funnel
extraction
(Acid/neutral,
base).
Generally good
recoveries, except
for some hydrophilic
phenols which gave
low recoveries.
No Chromatographic
interference due
to molecular sulfur.
Not analyzed.
(No recovery
data available).
Separatory
funnel
extraction
(Base/neutral,
acid).
Generally good
recoveries, except
for some hydrophilic
phenols which gave
low recoveries.
No Chromatographic
interference due
to molecular sulfur.
Not analyzed.
(No recovery
data available)
47
-------
IX. CONCLUSION
The necessity to dechlorinate effluents was shown by
results obtained from the chlorination of surrogate and
matrix spikes. Phenolic concentrations decreased and various
chlorophenols were produced. Under acid/neutral extraction
conditions, chlorinated derivatives of acenaphthene and
pyrene were also formed.
This study examined the suitability of three
dechlorinating agents: sodium thiosulfate, L-ascorbic acid
and sodium arsenite. Sodium thiosulfate. the compound
required by Method 625 (1), gave good results when
20 mg per liter of sample was employed. Analytical and
chromatographic problems were encountered when excess amounts
(2.5-5.0 g) were used, mainly due to the molecular sulfur
formed in the extraction process. These amounts were tested
since the reagent is added in the field and it is conceivable
that an excess could be added. The concentration of sodium
thiosulfate stated in Method 625 (80 mg/L) produced a
chromatographic interference of molecular sulfur when
extracted by the continuous extraction method, though this
level produced no problem when separatory funnel extraction
was used. For this reason, 20 mg of sodium thiosulfate
is recommended as an appropriate level for both types of
extractions.
Sodium arsenite in excess gave acceptable recoveries of
surrogate and matrix spike compounds, and presented no
analytical problems. However, it is not recommended for
field use due to its high toxicity. In addition, EPA
approval as an alternate test procedure would be required for
use of this compound in the analysis of NPDES samples (14).
The use of L-ascorbic acid has been recommended for
dechlorinating samples for volatile analysis. Problems were
encountered when excess amounts of this reagent were
employed. L-ascorbic acid produced an interference peak that
would interfere with the quantitation of bis(2-chloroiso-
propyl)ether. In addition, under base/neutral continuous
extraction conditions, it greatly decreased the recovery of
2,4-dinitrotoluene. When 80 mg of L-ascorbic acid per liter
of sample was used, good recoveries of 2,4-dinitrotoluene
were obtained (base/neutral, acid extraction conditions).
However, the unknown interference peak was observed in some,
but not all, of the extracts. The extraction recovery of
this unknown compound was highly variable when employing
L-ascorbic acid, and thus the interference peak represents a
possible source of contamination. For this reason, L-ascorbic
acid is not recommended as a suitable dechlorinating agent.
The results of this work have illustrated the importance
48
-------
of dechlorination of samples-for semi-volatile organic
analysis (EPA Method 625) (1). In addition, the importance
of careful dechlorination is evident. Sampling personnel
should be warned of the analytical problems associated with
the addition of excess dechlorinating agent. It is
recommended that sodium thiosulfate be carefully added to
chlorinated samples in 20 mg/L increments, with mixing and
verification of dechlorination using EPA method 330.4 (15) or
330.5 (16) between each addition.
49
-------
X. REFERENCES
(1) Method 625 "Base/Neutrals and Acids" Federal
Register/ Vol. 49, No. 209/Friday October 26, 1984:
Part VIII, Environmental Protection Agency, 40 CFR
Part 136, "Guidelines Establishing Test Procedures
For The Analysis Of Pollutants Under the Clean Water
Act; Final Rule And Interim Final Rule And Proposed
Rule.
(2) Mahan, B. H. College Chemistry. (Addison-Wesley
Publishing Company, Reading, Mass., 1966),
pp. 530-535.
(3) Gosselin, R.E., Hodge H.C., Smith, R.P. and Gleason,
M.N. Clinical Toxicology of Commercial Products
Acute Poisoning (The Williams and Wilkins Company,
Baltimore, 1976, 4th edition), pp. 4 and 92 of
Section II.
(4) Slater, R. "Note on Preservation of Drinking Water
Samples to be Analyzed for Volatile Organic Chemicals
(VOCs) and 1445 Monitoring Compounds" in EPA Quality
Assurance Newsletter ( U.S. E.P.A., Vol. 10, No. 1,
Jan. 1988, pp. 4-5.)
(5) Morrison, R.T. and Boyd, R.N. Organic Chemistry
(Allyn and Bacon, Inc., Boston, 1971, 2nd edition),
pp. 807-808.
(6) Hammer, M. J. Water And Waste-Water Technology.
(John Wiley and Sons, Inc., New York, 1975), p. 15.
(7) Slayton, J. L. and Trovato, E. R. "Acid/Neutral
Continuous Liquid/Liquid Extraction of Priority
Pollutants and Hazardous Substance List Compounds"
U.S. E.P.A. EPA/903-9-88-001, January 1988.
(8) U.S. E.P.A. Contract Laboratory Program.
Statement of Work for Oraanics Analysis. 7/87.
(9) Durrant, P. J. and Durrant, B. Introduction to
Advanced Inorganic Chemistry (John Wiley and Sons,
Inc., New York, 1970), pp. 766-767 and 855-856.
(10) Florkin, M. and Stotz, E.H., editors. Compre-
hensive Biochemistry Vol. 5 Carbohydrates
(American Elsevier Publishing Company, Inc., New
York, 1963), pp. 84-93.
(11) White, A., Handler, P. and Smith E.L. Principles
of Biochemistry (McGraw-Hill Book Company, New
York, 1964, 3rd edition), p. 973.
50
-------
(12) Newbold, B.T. and LeBlanc, R.P. "Reduction of
Substituted Nitrobenzenes. Part II. Reduction of
Some Aromatic Nitro-conpounds with Reducing Sugars"
J. Chem. Soc.(London), 1965, pp. 1547-1548 [36,72].
(13) Hudlicky, M. Reductions in Organic Chemistry
(Ellis Horwood Limited, Chichester, West Sussex,
England, 1984), pp. 70-73 and 182-183.
(14) Personal communication with Terry Grady, EPA-
EMSL, Cincinnati, 7/8/88.
(15) Method 330.4 "Chlorine, Total Residual" (Titri-
metric, DPD-FAS) U.S. E.P.A. Methods for
Chemical Analysis of Water and Wastes EPA-600/4-79-
020, March 1979.
(16) Method 330.5 "Chlorine, Total Residual" (Spectre-
photometric, DPD) U.S. E.P.A. Methods for Chemical
Analysis of Water and Wastes EPA-600/4-79-020,
March 1979.
51
-------
XI. APPENDIX
Additional Analytical Data
52
-------
TABLE 1A
EXPERIMENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
CHLORINATED EXTRACTS
COMPOUND
2-FLUOROPHENOL
D5-PHENOL
D5-NITROBENZENE
2-FLUORO-l,r-BIPHENYL
2,4,6-TRIBROHOPHENOL
D14-P-TERPHENYL
SAMPLE NUMBER
2 3
41.3
8.1
73
41.1
67.6
79.4
49.1
B.8
BO
62.2
78.3
90.4
AVERAGE
45.2
8.45
76.5
61.65
72.95
84.9
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 2 AND 3: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
-------
TABLE 2A
EXPERIMENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING SODIUM THIOSULFATE
COMPOUND
2-FLUOROPHENDL
D5-PHENOL
05-NITROBENZENE
2-FLUORO-l,l'-BIPHENYL
2,4,6-TRIBROMDPHENOL
D14-P-TERPHENYL
SAMPLE NUHBER
4 5 AVERAGE
SB. 7
65.3
66.7
56.4
70. B
72.4
44.7
53.7
55.3
50
65.2
66.3
51.7
59.5
61
53.2
68
69.35
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 4 AND 5: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
54
-------
TABLE 3*
EXPERIMENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY .
(REPORTED AS 1)
8ECHLORINATIDN USIHB SODIUN ARSENITE
CONFOUND
2-FLUOROPHENOL
D5-PHENDL
05-NITROBENZENE
2-FLUORO-l,r-BIPHENYL
2,4,6-TRIBRDHQPHENOL
B14-P-TERPHtNYL
SAHPLE NUtlBER
6 7 AVERAGE
63.6
72.2
74.9
61.4
86.2
91.2
76.5
B1.9
85.2
66.7
84.3
92.6
70.05
77.05
80.05
64.05
85.25
91.9
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 6 AND 7: CHLORINATED TO 0.7 PPH TOTAL CHLORINE
55
-------
TABLE 4A
EXPERIMENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLOR1NATION USINB L-ASCORBIC ACID
COKPOUND .
2-FLUOROPHENOL
D5-PHENDL
D5-NITROBENZENE
2-FLUORO-l,r-BIPHEHYL
2,4,6-TRIBROHDPHENDL
D14-P-TERPHENYL
SAMPLE NUMBER
8 9 AVERAGE
81.3
86
BB.2
73.9
95.5
95.5
79.4
B4.7
87.5
74.5
91
98. &
80.35
85.35
87.85
74.2
93.25
97.05
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 8 AND 9: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
56
-------
TABLE 4B
EIPERIHfNT B: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USINE L-ASCORBIC ACID
SAflPLE NUMBER
CLPLIHITS
OMPOUND 10 11 AVERAGE (HATER)
2-FLUDROPHENOL 85 74.5 79.75 21-100
D5-PHENOL 84.5 ' 77.6 81.05 10-94
US-NITROBENZENE BB.6 80.8 84.7 35-114
2-FLUORO-l,r-BIPHENYL 73.7 71.3 72.5 43-116
2,4,6-TRIBROHDPHENOL 81.2 86.8 84 10-123
D14-P-TERPHENYL 82.6 90.3 86.45 33-141
SAMPLES 10 AND 11: CHLORINATED TO 0.7 PPH TOTAL CHLORINE
-------
TABLE 5A
EIPERIflENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL,ACID)
HATRII SPIKE RECOVERY
(REPORTED AS I)
CHLORINATED EXTRACTS
CONFOUND
PHENOL
2-CHLOROPHENQL
1,4-D1CHLOROBENZENE
N-NITRDSODI-N-PROPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-BETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLORDPHENDL
DIBUTYLPHTHALATE
PYRENE
SAMPLE
2
8.2
100. B
72.6
75
76.6
32.1
85. b
66.8
75.8
54
30
79.6
NUMBER
3
10.6
110.6
78.6
78.6
83.6
35.2
90
66.7
83.5
57.3
39.4
85.7
AVERAGE
9.4
105.7
75.6
76.8
81.1
33.65
87.8
66.75
79.65
55.65
34.7
82.65
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 2 AND 3: CHLORINATED TO 0.7 PPH TOTAL CHLORINE
-------
TABLE 6A
EXPERIMENT A: CONTINUOUS EITRACTIDN (BASE/NEUTRAL, ACID)
HATRH SPIKE RECOVERY
(REPORTED AS Z)
DECHLORINATION USIN6 SODIUM THIOSULFATE
COMPOUND
SAMPLE NUHBER
PHENOL
2-CHLOROPHENDL
1,4-DICHLOROBENZENE
N-NITRDSODI-N-PROPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITRDPHENQL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
4
66. 5
67.6
70.2
71.9
71.7
73.7
76.3
82.3
75.5
72.8
35.4
73.3
5
55.7
57.5
57.7
60.8
60.8
62.6
69
58.1
67.3
56.5
26.5
65.9
AVERAGE
61.1
62.55
63.95
66.35
66.25
68.15
72.65
70.2
71.4
64.65
30.95
69.6
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 4 AND 5: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
-------
TABLE 7A
EXPERIMENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
MATRIX SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USIN6 SODIUM ARSENITE
CONFOUND
PHENOL
2-CHLOROPHENDL
1,4-DICHLOROBENZENE
N-NJTROSOD1-N-PROPYLAHINE
1,2,4-TRICHLDROBENZENE
4-CHLORO-3-HETHYLPHENDL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
SAMPLE NUMBER
6
77.1
78. 3
81.7
80.8
82.6
86.4
92.8
88. 8
89
75.1
45.1
89.3
7
82.9
81.6
86.4
90.8
85.7
85
90.2
81.3
91.6
86.6
56.2
93.4
AVERABE
80
79.95
84.05
85. B
84.15
85.7
91.5
.85.05
90.3
80.85
50.65
91.35
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 6 AND 7: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
-------
TABLE BA
EXPERIHENT A: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
MATRIX SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USIN6 L-ASCDRBIC ACID
COMPOUND
PHENOL
2-CHLOROPHENOL
1,4-DICHLOROBENZENE
N-NITROSODI-N-PROPYLABINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLORDPHENOL
DIBUTYLPHTHALATE
PYRENE
SAMPLE NUMBER
8 9 AVERAGE
89.7
82
89
92.1
86.4
92.7
90.2
100.1
60.4
108.9
55.3
93
86.1
77.7
87.4
91
86.3
91.6
89.6
94.4
61.1
104.1-
60.6
97.1
87.9
79.85
88.2
91.55
86.35
92.15
89.9
97.25
60.75
106.5
57.95
95.05
CLP LIMITS
(HATER)
12-B9
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 8 AND 9: CHLORINATED TO 0.7 PPM TOTAL CHLORINE
61
-------
TABLE BB
EXPERIMENT B: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
HATRII SPIKE RECOVERY
(REPORTED AS Z)
DECHLORINATION USIN6 L-ASCORBIC ACID
COMPOUND
PHENOL
2-CHLOROPHENOL
1,4-DICHLOROBENZENE
N-NITROSODI-N-PROPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-HETHYLPHENDL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
SAMPLE NUMBER AVERAGE
10
11
CLP LIMITS
(HATER)
90.7
90.5
90.9
93.7
90.8
91.7
92.1
85. 3
90
88
91.6
89.2
82.2
81.7
82.5
86.9
83.1
85.4
66
92.4
91.9
101
92.4
95.3
86.45
86.1
86.7
90.3
86.95
88.55
89.05
88.85
90.95
94.5
92
92.25
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 10 AND 11: CHLORINATED TO 0.7 PPH TOTAL CHLORINE
62
-------
TABLE 9A
EXPERIMENT D: CONTINUOUS EXTRACTION
AROMATIC NITRO COMPOUND RECOVERY
(REPORTED AS X)
DECHLORINATION USINB L-ASCORBIC ACID
COMPOUND
2,4-DINITRDTOLUENE
NITROBENZENE
EXTRACTS
BASE/NEUTRAL BASE/NEUTRAL ACID/NEUTRAL ACID/NEUTRAL CLP LIMITS
1 2 1 2 (HATER)
30.2
94.5
29.9
102.4
9B.6
105.9
94.6
105.5
24-96
NAt
B/N AND A/N EXTRACTS HERE CHLORINATED TO 0.9 PPM TOTAL CHLORINE
t NO LIMITS AVAILABLE
63
-------
TABLE IDA
EIPERIHENT E: CONTINUOUS EXTRACTION
BASE/NEUTRAL, ACID EXTRACTION
BINITRDTOLUENE RECOVERY
{REPORTED AS X).
DECHLORINATION USIN6 L-ASCDRBIC ACID
EXTRACTS
COIIPDUND BASE/NEUTRAL BASE/NEUTRAL BASE/NEUTRAL BASE/NEUTRAL CLP LIMITS
1 2 3 4 (MATER)
2,4-DINITROTDLUENE 87.8 90.2 91.1 98.2 24-96
2,6-DINITROTOLUENE 90.4 93.6 B6.4 90.0 NAt
ALL SAMPLES HERE CHLORINATED TO 0.6 PPK TOTAL CHLORINE
I NO LIMITS AVAILABLE
64
-------
TABLE HA
EXPERIMENT F: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLORINAT10N USING 80 H6/L SODIUH THIOSULFATE
CONFOUND
2-FLUOROPHENDL
D5-PHENOL
D5-NITROBEN2EHE
2-FLUORO-l,r-BIPHENYL
2,4,6-TRIBROHOPHENOL
D14-P-TERPHENYL
SAMPLE NUMBER
1 2 AVERA6E
93.2
95.8
95.7
92.4
90.5
89.2
80.8
8B.9
86.1
85.2
87.5
90.2
87
92.35
90.9
88.8
89
89.7
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 1 AND 2: CHLORINATED TO 1.6 PPM TOTAL CHLORINE
65
-------
TABLE 12A
EIPERIHENT F: CONTINUOUS EITRACTJON (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLDRINATIOti USING 80 N6/L SODIUH THIOSULFATE
SAMPLE NUMBER
CLP L1HITS
COMPOUND 3 4 AVERAGE (HATER)
2-FLUOROPHENOL 81.5 Bl.B 81.65 21-100
D5-PHENOL 87.7 86.5 87.1 10-94
D5-NITRDBENZENE 81.2 85 83.1 35-114
2-FLUORO-l,r-BIPHENYL 82 83.4 82.7 43-116
2,4,6-TRIBROHOPHENOL 90.3 89.1 B9.7 10-123
D14-P-TERPHENYL 83.2 85.6 84.4 33-141
SAMPLES 3 AND 4: CHLORINATED TO 1.6 PPH TOTAL CHLORINE
66
-------
TABLE 13A
EXPERIMENT F: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
MATRIX SPIKE RECOVERY
(REPORTED AS 1)
DECHLORINATION USIN6 BO HB/L SOD1UH THIOSULFATE
COrtPOUND
SAHPLE NUHBER AVERA6E
PHENOL
2-CHLOROPHENDL
1,4-DICHLOROBENIENE
N-NITRDSODI-N-PROPYLAHINE
1,2,4-TRICHLORDBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLEHE
4-NITROPHENOL
2,4-DINITRDTOLUENE
PENTACHLORDPHENOL*
DIBUTYLPHTHALATE
PYRENE
92.5
91.5
87. 6
111.4
89.3
96.5
87.9
100.2
97
107.5
97.4
90.3
93.7
88.8
81.8
102.4
83.8
97.9
84.7
103.3
91.4
116.9
97.9
92.9
93.1
90.15
84.7
106.9
86.55
97.2
86.3
101.75
94.2
112.2
97.65
91.6
CLP LIHITS
(HATER)
12-89
27-123
34-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 1 AND 2: CHLORINATED TO 1.6 PPH TOTAL CHLORINE
67
-------
TABLE 14A
EJPERIHENT F: CONTINUOUS EITRACTION (BASE/NEUTRAL, ACID)
HATRII SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING BO H6/L SODIUfl THIOSULFATE
CONFOUND
PHENOL
2-CHLOROPHENOL
1,4-DICHLOROBENZENE
N-NITROSODI-N-PROPYLAHINE
1,2,4-TRlCHLORQBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITRDPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
NBUTYLPHTHALATE
PYRENE
SAMPLE NUMBER AVERAGE
3
86.8
B7.5
77.1
87.7
77.7
84.1
79.4
91.4
79.3
108.3
56.8
83.3
4
83.4
84.2
7B.7
94.1
79.9
89.5
81.2
101.1
87.7
113.4
62.6
87.3
85.1
85.85
77.9
90.9
78.8
86. B
80.3
96.25
83.5
110.85
59.7
85.3
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 3 AND 4: CHLORINATED TO 1.6 PPH TOTAL CHLORINE
-------
TABLE ISA
EXPERIMENT F: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
SURROGATE SPIKE RECOVERY
(REPORTED AS X)
OECHLORINATIDN USING 20 H6/L SODIUH TNIOSULFATE
COMPOUND
2-FLUOROPHENOL
D5-PHENDL
OS-NITROBENZENE
2-FLUORO-l,l'-BIPHENYL
2,4,6-TRIBROMDPHENDL
N4-P-TERPHENYL
SAMPLE NUMBER
1 2 AVERAGE
98.6
94.8
91.3
103.6
96.8
96.2
90
91.4
93.9
92.7
93.3
89.8
94.3
93.1
92.6
98.15
95.05
93
CLP LIMITS
(NATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 1 AND 2: CHLORINATED TO 1.8 PPH TOTAL CHLORINE
69
-------
TABLE 16A
EXPERIMENT F: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS I)
DECHLDRINATION USING 20 HG/L SDDIUH THIOSULFATE
COMPOUND
2-FLUDROPHENDL
D5-PHENOL
OS-NITROBENZENE
2-FLUORO-l,r-BIPHENYL
2,4,6-TRlBROHOPHENOL
D14-P-TERPHENYL
SAMPLE NUMBER
3 4 AVERAGE
81.5
85.7
96.7
93.2
82.2
92.3
79.9
81.7
90.9
88.9
83.1
90.7
80.7
83.7
93.8
91.05
82.65
91.5
CLP LIMITS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 3 AND 4: CHLORINATED TO 1.8 PPM TOTAL CHLORINE
70
-------
TABLE 17A
EXPERIMENT F: CONTINUOUS EXTRACTION (ACID/NEUTRAL, BASE)
MATRIX SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING 20 H6/L SODIlffl THIOSULFATE
COMPOUND
SAMPLE NUHBER AVERAGE
PHENOL
2-CHLORDPHENDL
1,4-DICHLOROBENZENE
H-NITRDSOD1-N-PRDPYLAHINE
1,2,4-TRICHLORDBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
95.9
100.2
95.5
80.2
105.3
90.4
96.1
71.7
95
88. 1
94.4
90.2
91.9
91
86
B6.3
91.5
93.2
90.7
97.5
94.8
95.5
91.5
89. 7
93.9
95.6
90.75
83.25
98.4
91.8
93.4
84.6
94.9
91.8
92.95
89.95
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-116
10-80
24-96
9-103
11-117
26-127
SAMPLES 1 AND 2: CHLORINATED TO l.B PPH TOTAL CHLORINE
71
-------
TABLE 1BA
EXPERIMENT F: CONTINUOUS EXTRACTION (BASE/NEUTRAL, ACID)
MATRIX SPIKE RECOVERY
(REPORTED AS I)
DECHLORINATION USING 20 H6/L SODIUH THIOSULFATE
COMPOUND
SAMPLE NUMBER AVERAGE
PHENOL
2-CHLORDPHENOL
1,4-DICHLDROBENZENE
N-NITRDSODI-N-PRDPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-BINITROTOLUENE
PENTACHLDROPHENDL
DIBUTYLPHTHALATE
PYRENE
85.5
B3.B
87.3
90.2
90.4
90.7
90.3
81.7
94.4
76. 1
65
91.3
82.6
82.4
83
82.5
BB.7
88.2
88.8
82.3
92.7
79.6
65.5
90.4
84.05
83.1
85.15
86.35
89.55
89.45
89.55
82
93.55
78.85
65.25
90.85
CLP LIMITS
(HATER)
12-B9
27-123
36-97
41-114
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 1 AND 2: CHLORINATED TO l.B PPN TOTAL CHLORINE
72
-------
TABLE 19A
EIPERIHENT F: SEPARATORY FUNNEL EITRACTION (ACID/NEUTRAL, BASE)
SURROGATE SPIKE RECOVERY
(REPORTED AS X)
BECHLORINATION USINB BO HE/L SODIUM THIDSULFATE
COMPOUND
2-FLUOROPHENDL
D5-PHENOL
D5-NITROBENZENE
2-FLUORO-lfl'-BIPHENYL
2,4,6-TRIBROHOPHEHDL
U4-P-TERPHENYL
SAHPLE MHIBER
1 2 AVERAGE
50.4
33.9
94.8
88.1
95.1
95.9
60.1
37
94.1
90.5
90.6
94.6
55.25
35.45
94.45
89.3
92.85
95.25
CLP LIH1TS
(HATER)
21-100
10-94
35-114
43-116
10-123
33-141
SAMPLES 1 AND 2: CHLORINATED TO 1.6 PPH TOTAL CHLORINE
73
-------
TABLE 20A
EXPERIMENT F: SEPARATDRY FUNNEL EXTRACTION (BASE/NEUTRAL, ACID)
SURROGATE SPIKE RECOVERY
(REPORTED AS 1)
DECHLORINATION USING 80 H6/L SODIUM THIDSULFATE
SAMPLE NUMBER
CLP LIMITS
COMPOUND 3 4 AVERA6E (HATER)
2-FLUOROPHENOL 49.5 SO.B 50.15 21-100
D5-PHENOL 34 31.4 32.7 10-94
OS-NITROBENZENE 91.1 85.2 BB.15 35-114
2-FLUORO-l,r-BIPHENYL 77 74.8 76.9 43-116
2,4,6-TRIBROHOPHENOL 84.2 79.4 81.B 10-123
D14-P-TERPHENYL 93.8 90.3 92.05 33-141
SAMPLES 3 AND 4: CHLORINATED TO 1.6 PPM TOTAL CHLORINE
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TABLE 21ft
EXPERIMENT F: SEPARATORY FUNNEL EXTRACTION (ACID/NEUTRAL, BASE)
HATRII SPIKE RECOVERY
(REPORTED AS Z)
DECHLDR1NATION USING BO HS/L SODIUM THIOSULFATE
COMPOUND
SAMPLE NUMBER AVERA6E
PHENOL
2-CHLOROPHENOL
1,4-DlCHLOROBENZENE
N-NITRDSODI-N-PROPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-HETHYLPHENOL
ACENAPHTHYLENE
4-NITROPHENOL
2,4-DINITROTOLUENE
PENTACHLORDPHENOL
DIBUTYLPHTHALATE
PYRENE
34.4
87.3
59.5
101.5
62.8
93.2
80.3
26.2
83.5
99.6
86.4
83.5
39.8
90.5
72
93.4
75.8
92
88.1
10.9
89.8
75.3
93.8
91.2
37.1
88.9
65.75
97.45
69.3
92.6
84.2
18.55
86.65
87.45
90.1
87.35
CLP LIMITS
(HATER)
12-89
27-123
36-97
41-116
39-98
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 1 AND 2: CHLORINATED TO 1.6 PPH TOTAL CHLORINE
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TABLE 22A
EIPERIHENT F: SEPARATOR! FlBQB. EITRACTIOH (BASE/NEUTRAL, ACID)
MTRII SPIKE RECOVERY
(REPORTED AS I)
OECHLORINATION USIN6 80 H6/L SODIUM THIOSULFATE
COHPOUND
SAMPLE mm AVERAGE
PHENOL
2-CHLOROPHENQL
1,4-DICHLOROBENZENE
K-N1TROSODI-N-PROPYLAHINE
1,2,4-TRICHLOROBENZENE
4-CHLORO-3-METHYLPHENDL
ACENAPHTHYLENE
4-NITROPHENQL
2,4-DINITROTOLUENE
PENTACHLOROPHENOL
DIBUTYLPHTHALATE
PYRENE
34.5
BO. 6
60.7
115.1
64
84.3
90.6
25.7
96.7
64.8
B5.B
94.4
34.3
80
', 62
86.7
63.5
80.6
81.6
3.5
83.3
53
74.5
85.3
34.4
80.3
61.35
100.9
63.75
82.45
86.1
14.6
90
68.9
80.15
89.85
CLP LIMITS
(HATER)
12-B9
27-123
36-97
41-116
39-9B
23-97
46-118
10-80
24-96
9-103
11-117
26-127
SAMPLES 3 AMD 4: CHLORINATED TO 1.6 PPH TOTAL CHLORINE.
76
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