United States
Environmental Protection
Agency
National Exposure
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-97/140 April 1998
Project Summary
Acetonitrile Field Test
Joette L. Steger, Joan T. Bursey, and David Epperson
Abstract
Field experiments were conducted at
a hazardous waste incinerator. The
ability of a specially-designed sampling
train to quantitatively collect acetoni-
trile was evaluated. Ten quadruple runs
were conducted. Each run consisted of
four acetonitrile sampling trains sam-
pling simultaneously. The sampling and
analytical methods were evaluated us-
ing Method 301 ("Protocol for the Field
Validation of Emission Concentrations
from Stationary Sources") statistical
procedures.
The acetonitrile sampling train was
based on the Method 0010 train which
collects semivolatile compounds on
Amberlite XAD-2® sorbent. The Method
0010 train was modified by replacing
the Amberlite XAD-2® with Carboxen™-
1000. Forty-eight grams of 45/60 mesh
Carboxen™-1000 were used.
The acetonitrile sampling train was
evaluated in the field to demonstrate
its ability to determine acetonitrile in
the gaseous waste stream from a haz-
ardous waste incinerator. Two of the
quadruple trains were dynamically
spiked with an aqueous solution of
acetonitrile. Method 301 statistical
analysis was performed. The mean re-
covery for the 20 spiked trains was
100%. The relative standard deviation
in the measured acetonitrile for the 20
spiked trains and for the 20 unspiked
trains was within the Method 301 crite-
ria of <50%. The calculated bias was
insignificant; therefore, a bias correc-
tion factor was not needed.
This report was submitted in fulfill-
ment of EPA Contract No. 68-D4-0022
by Eastern Research Group under the
sponsorship of the United States En-
vironmental Protection Agency. This
report covers a period from February
21, 1996 to September 30, 1996, and
work was completed as of September
30, 1996.
This Project Summary was developed
by the National Exposure Research
Laboratory's Human Exposure and At-
mospheric Sciences Division, Research
Triangle Park, NC, to announce key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report
ordering information at back).
Introduction
There is a wide interest in developing
and evaluating a method for measure-
ment of acetonitrile emissions from sta-
tionary sources of air pollution. Acetoni-
trile is a component of many industrial
hazardous waste streams, especially from
fiberglass and synthetic fiber manufactur-
ing. Acetonitrile is listed as one of the
most difficult compounds to incinerate ac-
cording to the University of Dayton Re-
search Institute incinerability ranking.1 Ac-
etonitrile has been suggested as an ex-
cellent non-halogenated compound to use
as a hazardous constituent spike during
Resource Conservation and Recovery Act
(RCRA) Subpart-B trial burn tests. Lack of
an effective sampling and analysis method
has prevented its utilization. Eastern Re-
search Group, under contract to the U.S.
Environmental Protection Agency (EPA),
has developed and evaluated a method
for sampling and analyzing acetonitrile
from stationary sources. The results of a
field test of that method are provided in
this project summary.
Laboratory evaluation of a sorbent based
sampling method using the modified
Method 00102 train was completed on WA
4 of Contract 68-D4-0022. Final labora-
tory method evaluation indicated that 48
grams (g) of Carboxen™-1000 (the amount
that fits in a Method 00102 sorbent mod-
ule) is sufficient to collect and recover 90
to 100% of the acetonitrile under the con-
ditions tested. Greater than 90% of the
acetonitrile can be recovered by eluting
the sample from the sorbent. The esti-
mated detection limit for the method is 60
ppbv (100 jag/m3).
A field test of the acetonitrile sampling
train developed in the laboratory was con-
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ducted under this work assignment (WA
45 of Contract 68-D4-0022). The field test
experimental design followed guidance
outlined in EPA Method 301,3 "Protocol
for the Field Validation of Emission Con-
centrations from Stationary Sources," 40
Code of Federal Regulations (CFR) Part
63. The field test data were used to deter-
mine the method's precision and accu-
racy.
The field test used a "quad train" ap-
proach in which four acetonitrile sampling
trains were operated simultaneously to
collect flue gas samples. A Method 00102
sampling train, modified by placing
Carboxen™-1000 in the sorbent module,
was used to collect gaseous acetonitrile
from a hazardous waste incinerator. The
acetonitrile was then desorbed from the
Carboxen™-1000 with methylene chloride.
The resulting organic extract was ana-
lyzed by gas chromatography with flame
ionization detection (GC/FID).
Experimental Approach
The purpose of the sampling program
was:
• To evaluate the laboratory developed
acetonitrile sampling and analytical
methods, and
• To determine the performance (preci-
sion and accuracy) of the laboratory
developed methods under field con-
ditions.
The field test included ten quadruple
runs. For each quadruple run, four inde-
pendent flue gas samples were collected
simultaneously from an incinerator emis-
sion source. Two of the flue gas streams
were dynamically spiked with known con-
centrations of acetonitrile. The precision
of the test method was estimated from the
variation in results obtained for pairs of
spiked and unspiked samples. Accuracy
(bias) was determined from the differences
between the spiked and measured quanti-
ties of acetonitrile.
Both the sorbent extract and conden-
sate samples collected from each of the
trains were analyzed for all of the quad
runs to determine whether acetonitrile
breaks through the sorbent. The impinger
components of the trains were not ana-
lyzed and were archived.
For Run 4 (Day 2) and Run 5 (Day 3),
five of the seven recovered components
were analyzed separately. These five com-
ponents are:
• The rinse of the front half of the filter
housing;
• The 1:1 methylene chloride:methanol
extract of the filter;
• The methylene chloride extract of the
sorbent;
• The rinses of the back half of the
filter housing and condenser; and
• The condensate and condensate
rinses.
Probe rinses were collected at the end
of each day. The probe rinses from the
second and third day were also analyzed,
in order to coincide with the detailed analy-
ses performed on Runs 4 and 5 taken on
the same days. The analytical results from
these six components were examined.
Because no acetonitrile was detected in
these fractions, the Work Assignment Man-
ager (WAM) decided not to analyze the
rinse of the front half of the filter housing,
the 1:1 methylene chloride:methanol ex-
tract of the filter, the rinses of the back
half of the filter housing and condenser
for the remaining eight quad trains. For
the same reason, the WAM also decided
not to analyze the probe rinses from the
remaining test days. The analytical results
from the sorbent extract and condensate
samples were combined for statistical
analysis.
Spiking
Two of the four trains making up the
quad assembly were spiked during each
quad run. Ten complete quad runs re-
sulted in a total of 20 spiked and 20
unspiked trains. Acetonitrile in water was
used to spike the trains. Acetonitrile was
spiked at a level equivalent to 45 + 5
ppmv (73+8 milligrams [mg] total) in the
flue gas stream. (No acetonitrile was de-
tected in the pre-test site survey samples.)
The spiking procedure for the field vali-
dation was identical to that used in the
laboratory study for acetonitrile. During each
quad run, standard acetonitrile solution was
introduced to two of the four trains. The
flow rate of the liquid spike into each train
was nominally 0.25 to 0.33 mL/min. This
spike rate resulted in the introduction of 55
to 91 mg of acetonitrile in each spiked
acetonitrile train over a 1-hour sampling
period. Approximately 960 L (34 ft3) of
sample were collected.
Precision and Accuracy
Assessment
This test program was designed to as-
sess precision and accuracy. Precision is
defined as the estimate of variability in the
data obtained from the entire measure-
ment system (sampling and analysis). At
least two (paired) sampling trains are
needed to establish precision. Accuracy
(bias) is defined as any systematic posi-
tive or negative difference between the
measured value and the true value. Per-
cent recovery is defined as any gain or
loss of a given compound compared to a
known spiked value.
Ten quad runs (40 sample trains) were
scheduled during the testing program. All
40 independent trains were completed and
accepted during the test period. This
completion rate exceeded the minimum
requirement of at least six quad runs (24
independent trains) for statistical analysis
by Method 301.3 This number of runs pro-
vided a sample population large enough
to produce credible data quality assess-
ments as described later in this section.
The latest version of the "Protocol for
the Field Validation of Emission Concen-
trations from Stationary Sources" (EPA
Method 301 )3 describes the data analysis
method necessary to evaluate both the
bias and the precision of emission con-
centration data from stationary sources.
Method 3013 was used for the statistical
evaluation of the test data for this field
evaluation.
Additional assessment of the precision
and accuracy using criteria from the Qual-
ity Assurance/Quality Control (QA/QC) Pro-
cedures for Hazardous Waste Incinera-
tion Handbook(EPA/625/6-89/023, Janu-
ary 1990)4 was also performed using the
criteria for SW 846 Method 00102 (+50%
accuracy and 50% precision).
Results and Discussion
Field Sampling
Ten quad train runs were completed at
the field test site. The static pressure in
the stack was positive, and remained con-
stant at approximately 6.35 mm (0.25
inches) of water during all test runs. The
average sample volume collected was
0.959 + 0.041 dry standard cubic meters
(33.9 + 1.5 dry standard cubic feet). The
sampling time was 60 minutes. Moisture
values ranged from 15 to 28% by volume.
Moisture values were low (15%) for one
run because the process was interrupted
during the run. The process interruption
did not affect the test data. The source
did not contain acetonitrile so acetonitrile
levels in the unspiked trains were not re-
duced.
The stack temperature and velocity for
each run were measured using a single
thermocouple and S-Type pitot tube on
the sampling probe assembly. Individual
stack gas temperature and pitot tube dif-
ferential pressure measurements were
taken every 10 minutes for each of the
four trains at the time the other stack
sampling data (gas meter reading, probe
temperature, etc.) were recorded. This
measurement scheme resulted in some
slightly different temperature and velocity
data for individual trains for the same run,
even though measurements were made
with a common probe. These temperature
and differential pressure measurement dif-
-------
ferences did not affect the test data be-
cause the sample for all four trains was
collected from the same point, the vol-
umes collected were recorded, and the
data were corrected for the slight differ-
ences in sample volume.
The percent isokinetic determination was
slightly outside of the 90 to 110% criteria
for four trains. These excursions outside
the isokinetic criteria did not affect the test
data because no acetonitrile was present
in the source. The spiking system was
operated to inject approximately equal
quantities of spiking solution into the two
spiked trains during each sampling run.
The actual amounts spiked varied from
train to train because the syringe pumps
did not always deliver exactly the same
amount of spiking solution. Spiked quanti-
ties were determined by weighing the spik-
ing syringes before and after each test
run. The density of the spike solution was
assumed to be 1 g/mL. An average of
72.7 + 7.7 mg of acetonitrile was spiked
into the trains.
Analysis
The samples were collected in seven
fractions: 1) the probe rinse, the rinse of
the front half of the filter housing, the
filter, the rinse of the back half of the filter
and the condenser rinse, the sorbent, the
condensate, and the impinger contents.
The probe rinse was collected at the end
of each day. The other fractions were
collected for each train. Runs 4 and 5 had
two sorbent fractions. All of the fractions
for Runs 4 and 5, except for the impinger
fraction, were analyzed. Runs 1 through 3
and Runs 6 through 10, had one sorbent
fraction. Only the sorbent and condensate
fractions were analyzed for these runs.
Sorbent Results
All 40 first sorbents from all 10 runs and
eight second sorbents from Runs 4 and 5
were analyzed. All of the acetonitrile val-
ues reported for the sorbents from the
unspiked trains were extrapolated beyond
the lowest point of the calibration curve
and are estimated values only.
For the spiked trains, the first sorbent in
the train collected from 68 to 114% of the
spiked acetonitrile. These percentages
equate to 47 to 104 mg. Thus, the capac-
ity of the sorbent appears to be at least
104 mg of acetonitrile, 1.04 m3, and 303.3
g of water. Method performance may de-
crease when greater than 104 mg of ac-
etonitrile is collected, or when more than
1.04 m3 of air is sampled, or more than
303.3 g of water is condensed from the
source.
Condensate Analysis
All 40 condensates from all 10 runs
were analyzed. Acetonitrile was detected
only in the condensates of the spiked
single sorbent trains. No acetonitrile was
detected in the condensate from Run 6.
Run 6 contained less moisture because
the process was interrupted during the
run.
For the other 14 spiked single sorbent
trains, the condensate in the train col-
lected from <1 to almost 11 mg of aceto-
nitrile. An average of 4 mg of acetonitrile
was detected in these condensates. The
relative standard deviation was 64%. The
high relative standard deviation indicates
that there is much variability in the amount
of acetonitrile collected in the condensate.
Acetonitrile Recovery
The percentage of acetonitrile recov-
ered in all of the analyzed components of
each spiked sampling train ranged from
74 to 119% for the 20 spiked trains. The
average recovery was 100%. The relative
standard deviation was 13%.
Acetonitrile Breakthrough
The second sorbent module in Runs 4
and 5 were analyzed. Therefore, break-
through of acetonitrile into the second sor-
bent could be examined. Any amount of
compound detected in the second sorbent
was classified as having broken through
the first sorbent module.
For the four spiked double sorbent mod-
ule trains, breakthrough ranged from 2 to
8%. The average breakthrough was 4%.
The relative standard deviation was 90%.
Three of the trains exhibited 2% break-
through. One train exhibited 8% break-
through. Thus, breakthrough of acetoni-
trile was inconsistent. No reason was iden-
tified to explain why breakthrough was
higher in the one train.
The condensate fraction was analyzed
for Runs 1 through 3 and Runs 6 through
10. Therefore, breakthrough of acetoni-
trile into the condensate could be esti-
mated. Acetonitrile is not quantitatively
collected in water. Thus, some of the ac-
etonitrile that broke through the sorbent
may not have been collected. Therefore,
breakthrough calculations for the single
sorbent modules may be biased low. Any
amount of acetonitrile detected in the con-
densate was classified as having broken
through the sorbent module.
No acetonitrile was detected in the con-
densate for the unspiked single sorbent
module trains. Thus, no breakthrough
analysis was possible using these
samples. For the 16 spiked double sor-
bent module trains, breakthrough ranged
from 0 to 11%. The average breakthrough
was 5%. The relative standard deviation
was 73%.
Two of the trains exhibited 0% break-
through. These were the two spiked trains
collected when the process went down.
Thus, less moisture was collected during
this run than during the other runs. The
amount of moisture in the source may
contribute to the amount of acetonitrile
that breaks through the sorbent.
One train exhibited 11% breakthrough.
Calculated breakthrough for all of the other
trains was less than 10%. Again, break-
through of acetonitrile was inconsistent.
No explanation of why breakthrough was
higher in some trains was identified. Break-
through was <10% for 95% of the spiked
trains. For 50% of the spiked trains, break-
through was <5%. Use of two sorbent
modules in series may be necessary when
sampling sources containing >15% mois-
ture.
Statistical Analysis
Method validation statistics were gener-
ated according to EPA Method 3013 guide-
lines. Data for all analyzed fractions from
all ten runs were used. Before statistical
analysis, all compound quantities from the
analytical reports were normalized using
the gas volume sampled by each train.
Normalization of the data was required
because each train collected slightly dif-
ferent sample volumes.
Results for the statistical analysis for
acetonitrile were RSDs of 13% for the 20
spiked samples and 17% for the 20
unspiked samples and a bias of 0.07 mg.
The bias was insignificant so no correc-
tion factor was required. Using the criteria
of 50% maximum for the RSD and 1.000
+ 0.300 for the bias correction factor, the
method validation test was successful for
acetonitrile.
The acetonitrile train also meets the
criteria from the Quality Assurance/Qual-
ity Control (QA/QC) Procedures for Haz-
ardous Waste Incineration Handbook
(EPA/625/6-89/023, January 1990)4 for SW
846 Method 0010.2 The average recovery
of 100% is within the QA Handbook4 crite-
ria of +50% accuracy. The relative stan-
dard deviation for the spiked trains of 13%
is within the QA Handbook4 criteria of
50% precision.
Discussion
Three statistical comparisons of the data
were made. Total acetonitrile recovered in
the train was compared to acetonitrile re-
covered in the first sorbent module. Total
acetonitrile recovered was also compared
to acetonitrile breakthrough. Finally, ac-
etonitrile recovered in the first sorbent
module was compared to acetonitrile
breakthrough. A >90% correlation existed
between the total recovery and the amount
recovered from the first sorbent module.
This correlation indicates that any action
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that will increase the retention on and
recovery from the first sorbent module will
improve the performance of the train.
No correlation was found between the
total acetonitrile recovered and the amount
of acetonitrile that broke through the first
sorbent module. Also, no correlation was
found between the acetonitrile recovered
on the first sorbent module and the amount
that broke through. As expected, in gen-
eral, the recovery on the first sorbent mod-
ule increased as the breakthrough de-
creased.
The effect of gas volume sampled and
moisture collected on the total acetonitrile
recovery, the recovery of acetonitrile in
the first sorbent, and the acetonitrile break-
through was also investigated. No corre-
lation was found between the volume of
gas sampled and the total acetonitrile re-
covery, the recovery of acetonitrile in the
first sorbent or the acetonitrile break-
through. No correlation was found between
the moisture collected and the total aceto-
nitrile recovery or the recovery of acetoni-
trile in the first sorbent.
A slight correlation (33%) was found
between the moisture collected and the
percent acetonitrile that broke through the
first sorbent module. As the moisture col-
lected increased, the breakthrough in-
creased. This slight correlation may indi-
cate that the performance of the train may
be dependent on the amount of moisture
present in the source. Additional perfor-
mance studies of the sampling train should
be conducted to determine if a limit on the
amount of moisture which can be col-
lected needs to be added to the method.
Carboxen™-1000 should also be a suit-
able sorbent for collecting other polar, wa-
ter soluble compounds such as alcohols,
ketones, and ethers. Additional perfor-
mance studies should be conducted to
expand the acetonitrile method to other
compounds listed in the Clean Air Act,
such as methyl ethyl ketone and methyl
isobutyl ketone.
Conclusions and
Recommendations
The work completed on WA 45 used a
modified Method 00102 train at a hazard-
ous waste incinerator to collect and mea-
sure acetonitrile. The Method 00102 train
was modified by using 48 g of Carboxen™-
1000 in place of the Amberlite® XAD-2
sorbent. The following conclusions are
based on the results of this work:
• The acetonitrile train, consisting of a
Method 00102 train with 48 g of
Carboxen™-1000 in the sorbent mod-
ule, successfully samples and collects
acetonitrile from stationary gaseous
emission sources.
• The bias calculated for acetonitrile
using Method 3013 statistical proce-
dures was insignificant. Thus, no bias
correction factor is needed.
• The relative standard deviations were
13% for spiked trains and 17% for
unspiked trains. These standard de-
viations are within the Method 3013
criteria of < 50%.
• The mean recovery of 100% and rela-
tive standard deviation of 13% for the
spiked trains is within the EPA's Qual-
ity Assurance Handbook 4 require-
ments of 50 to 150% recovery and
50% relative standard deviation.
• Greater than 90% of the recovered
acetonitrile was collected on the
Carboxen™-1000. Essentially no ac-
etonitrile was collected in the probe
rinses, in the rinse of the front half of
the filter holder, or on the filters.
• For the four spiked trains containing
dual sorbent modules, less than 2%
of the acetonitrile broke through to
the second module for three of the
trains and less than 8% broke through
in the fourth train.
• For the 16 spiked trains containing
single sorbent modules, less than 5%
of the acetonitrile broke through to
the condensate for eight of the trains
and less than 9% broke through for
15 trains.
The following recommendations are
based on the results of this study:
• Evaluate the acetonitrile sampling train
for other polar, water soluble com-
pounds such as methyl ethyl ketone,
methyl isobutyl ketone, acetone, and
quinone.
• Use two sorbent modules in series
when sampling sources containing
>15% moisture.
• Investigate improved or alternate pro-
cedures for desorbing the
Carboxen™-1000 to recover the ac-
etonitrile. Possible alternate proce-
dures include using high-pressure,
low-temperature extraction tech-
niques.
• Develop and test procedures for re-
covering and reactivating used
Carboxen™-1000.
• Evaluate the acetonitrile sampling train
at a second field site at a source
other than a hazardous waste incin-
erator. The evaluation should include,
in addition to acetonitrile, other polar,
water soluble compounds such as
methyl ethyl ketone and methyl isobu-
tyl ketone.
Acknowledgments
Under EPA Contract No. 68-D4-0022
Eastern Research Group prepared this
report with the supervision and guidance
of Mr. Robert Fuerst, EPA Work Assign-
ment Manager, in the National Exposure
Research Laboratory, Air Measurements
Research Division, Methods Branch, Re-
search Triangle Park, North Carolina. The
Eastern Research Group Project Man-
ager was Joan T. Bursey, and the Princi-
pal Investigator was Joette L. Steger. We
wish to acknowledge the contributions of
the following individuals to the success of
this program: Amy Bederka, Jenia Doerle,
Danny Harrison, Jim Howes, Linh Nguyen,
and Mark Owens.
References
1. Environmental Science and Technol-
ogy, 24, pp 316-328, 1990.
2. EPA Methods 0010, Test Methods for
Evaluating Solid Waste: Physical/
Chemical Methods. S-W-846, Third
Edition, September 1988, Office of Solid
Waste and Emergency Response, U.S.
Environmental Protection Agency,
Washington, DC 20460.
3. U.S. Environmental Protection Agency.
Method 301, Protocol for the Field
Evaluation of Emission Concentrations
from Stationary Sources. Code of Fed-
eral Regulations, Title 40, Part 63.
Washington, DC. Office of the Federal
Register. July 1, 1987.
4. U.S. Environmental Protection Agency.
Quality Assurance/Quality Control(QA/
QC) Procedures for Hazardous Waste
Incineration Handbook. EPA/625/6-89/
023, Center for Environmental Re-
search Information, Office of Research
and Development, U.S. Environmental
Protection Agency, Cincinnati, OH
45268. January 1990.
Disclaimer
The information in this document has
been funded wholly by the United States
Environmental Protection Agency under
EPA Contract Number 68-D4-0022 to East-
ern Research Group. It has been sub-
jected to Agency review and approved for
publication. Mention of trade names or
commercial products does not constitute
endorsement or recommendation for use.
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Joette L Stager, Joan T. Bursey, and David Epperson are with Eastern Research
Group, Inc., Morrisville, NC 27560.
Robert G. Fuerst is the EPA Project Officer (see below).
The complete report, entitled "Acetonitrile Field Test," (Order No. PB98-133143;
Cost: $49.00, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Human Exposure and Atmospheric Sciences Division
National Exposure Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
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