vvEPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S7-81 -136 Dec. 1981
Project Summary
On-Site GC/MS Analysis of
Chapman Gasification
Separator Liquor
C. J. Thielen, R. A. Magee, and R. V. Collins
This report gives results of a study to
characterize a wastewater stream from
a coal gasification facility using on-
site extraction and GC/MS analysis.
Objectives of the program were to:
• Characterize the wastewater or-
ganic components primarily for
selected Priority Pollutants, Ap-
pendix C, and synfuels com-
pounds.
• Investigate the stability of these
compounds under refrigeration
and ambient storage.
• Evaluate the removal of organics
by diisopropyl ether extraction
and wet oxidation.
Extractable material in the waste-
water consisted primarily of phenols
and alkylphenols. These compounds
account for about 99 percent of the
total mass identified. Several poly-
nuclear aromatic (PNA) compounds
were also identified. Deterioration in
the composition of the sample was
observed even though the water was
held in amber bottles at 4°C. This was
most evident in the concentration of
dimethylphenols which dropped ap-
proximately 75 percent during 2 weeks
of refrigerated storage. Ambient
sample storage produced a greater
decrease in the concentration of
phenol but did not appear to affect the
alkylphenols or the base/neutral com-
pounds as much. It is expected that
the observed changes in composition
would hamper any off-site wastewater
treatability studies with waters of this
type. The diisopropyl ether (DIPE)
extraction confirmed the 99+ percent
removal efficiency of phenol which
had been demonstrated in previous
studies. Wet oxidation removed or-
ganics almost as efficiently as DIPE
extraction but may have limited use
due to its high cost of operation.
This Project Summary was devel-
oped by EPA's Industrial Environmen-
tal Research Laboratory, 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
Radian Corporation has been con-
ducting environmental assessment
studies of low- and medium-Btu coal
conversion facilities under contract to
the Environmental Protection Agency
over the past 5 years. A Chapman-
Wilputte coal gasification facility was
the first source characterized in such an
assessment. The plant, in continuous
operation and in the U.S., is an easily
accessible source of coal gasification
wastewater. Three previous studies
examined this water as part of an
environmental data base for coal con-
version technologies. This data base
will provide input to the planning and
design of future gasification facilities
and formulation of regulations for water
discharges. This program characterized
the separator liquor and aqueous process
condensate from the Holston plant
under conditions which minimized
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sample deterioration. This allowed a
more accurate determination of the
composition of the waste stream.
Hewlett-Packard provided a Model HP-
5993B GC/MS for use on the program
and technical support for maintenance
of the instrument.
Objectives
Primary objectives of the program
were to:
• Characterize the separator liquor.
This included sampling over a 100-
hour monitoring period to determine
the average composition and varia-
bility of the identified compounds.
• Determine sample stability by
monitoring one sample for a month
for deterioration of identified com-
pounds.
• Investigate methods for reducing
the levels of organic materials in
the wastewater by wet oxidation
and diisopropyl ether (DIPE) ex-
traction.
In addition to these objectives, the
feasibility and utility of the operation of
a GC/MS system installed in a mobile
laboratory designed for field use was
evaluated.
Conclusions
The mobile GC/MS program provided
a more accurate characterization of the
separator liquor than had been previously
achieved. EPA Priority Pollutant Appen-
dix A base/neutral, acid extractable,
and volatile organic compounds. Ap-
pendix C compounds, and 57 organic
species of environmental interest were
quantitated. Of these, the Consent
Decree Appendix A volatile (purgeable)
organic compounds, the Appendix C
compounds, and the 57 additional or-
ganics had not been quantitated during
previous studies. Phenolic compounds
appear to represent essentially all of the
total chromatographable organic (TCO)
material in the acid fractions and most
of the material in the base/neutral
fractions.
Using a methylene chloride/diethyl
ether extraction procedure for base/
neutral and acidic compounds, it was
observed that a high percentage of the
phenolic compounds (usually found
only in the acid fraction) were extracted
into the base/neutral fraction. There-
fore, in order to obtain more accurate
values for the concentrations of phenolic
compounds in the separator liquor, both
the acid and base/neutral fractions
were analyzed and the values for phenolic
compound concentrations in each frac-
tion were added to give the value for
total phenolic compound concentration.
Extractions of aliquots taken periodi-
cally from the same water sample
indicate some loss of organic material
over a period of time. This is especially
true of the alkylphenols. This observa-
tion is corroborated by a comparison of
mobile GC/MS data with similar data
from previous wastewater studies.
Such a comparison shows that the
immediate extraction and analysis of
the wastewater on-site yielded higher
concentrations of phenolic, as well as
base/neutral extractable, compounds.
It is believed that the observed changes
in composition imply degradation that
would hamper any off-site wastewater
treatability studies with waters of this
type.
Results from this program confirm the
99 percent removal efficiency of phenols
by diisopropyl ether extraction found in
previous work and also show a 90
percent removal efficiency of phenol
and alkylphenols by wet oxidation. Wet
oxidation demonstrated a potential
advantage over biological treatment of
wastewater: it can reduce the levels of
many organic compounds which are
resistant or moderately resistant to
biodegradation. Wet oxidation is ex-
pensive and has been used only on a
very limited basis. Therefore, it may not
be economically feasible on an industry-
wide basis.
Recommendations
The recommendations below are
given for two major categories:
• Analytical methodologies.
• Additional studies which would
provide complementary data to this
study.
Analytical Methodologies
Recommendations for analytical
methodologies relate to some of the
difficulties encountered during sample
analysis and data reduction.
The major analytical difficulty was
associated with the extraction of the
phenols into the base/neutral fraction.
Due to the high concentration of phenolic
compounds, better partitioning of acid
and base/neutral compounds is required.
This might be achieved by:
• An acid/neutral followed by a
basic extraction, then separation of
acid and neutral compounds.
• Less vigorous extraction of base/
neutral compounds, using only
methylene chloride for the base/
neutral compounds, but continuing
with methylene chloride/diethyl
ether extraction for the acidic
compounds.
For each suggested procedure modifica-
tion, extraction efficiencies must be
determined by performing the separation
procedure with controls consisting of
known quantities of standard compounds
added to samples of the separator liquor
as well as water blanks.
The procedure for analysis of a sample
of this complexity should be refined to
provide a more cost effective approach.
The necessity of using GC/MS for every
analysis has not been established;
these analyses might be performed as
accurately with a gas chromatograph
equipped with a flame ionization de-
tector and capillary column. The capillary
column would provide better separation
and detection of the compounds than
packed columns. Once retention times
are determined adequately for com-
pounds of interest, GC will be more cost
effective than GC/MS. Periodic con-
firmation of compound identifications
by GC/MS would still be required.
Future studies should also incorporate
an experimental determination and
documentation of the variability associ-
ated with the sampling and analytical ,
procedures. (
The necessity of on-site extraction
and analysis versus on-site extraction
followed by off-site analysis should also
be investigated. The stability of the
extracted samples should be evaluated
by analysis of the extract immediately
after extraction and at predetermined
intervals following the extraction in
order to monitor any decrease jn the
concentration of one or more compounds.
If the stability of extracted samples is
adequate to allow transport and storage,
the expense of providing on-site analyti-
cal capabilities could be avoided.
Additional Studies
During this program the separator
liquor from the plant was characterized
for organic content:
• Immediately following collection.
• Periodically over a period of a
month under refrigerated storage.
• After a period of 3 weeks at room
temperature storage.
• Following DIPE extraction performed
immediately after collection.
• Following wet oxidation performed
immediately after collection.
Additional studies which characterize
the wastewater after biological treat-
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merit would supplement the information
already obtained. A more complete set
of data would then be available when
water treatment information is required
for selection of treatment schemes for
wastewater streams of similarcomposi-
tion.
The feasibility of operating a GC/MS
in a mobile laboratory was successfully
demonstrated in this program. The HP-
5993B has a data processing software
package capable of identifying and
quantitating compounds in conventional
samples in 10 to 15 minutes. This
feature makes a field GC/MS invaluable
when results are required quickly.
However, the sample matrix of the
separator liquor was a complex mixture
of many isomers. The resolution provided
by the packed column was not sufficient
to allow the software to distinguish the
quantitating ions for each isomer. Con-
sequently, extensive manual data in-
terpretation was required. If adequate
separation of the isomers could be
achieved, as with a capillary column,
then the software package should be
able to function as designed, providing
identification and quantitation of com-
pounds in a short amount of time.
C. J. Thielen, R. A. Magee, andR. V. Collins are with Radian Corporation, P.O.
Box 9948, Austin, TX 78766.
William J. Rhodes is the EPA Project Officer (see below).
The complete report, entitled "On-Site GC/MS Analysis of Chapman Gasifica-
tion Separator Liquor," (Order No. PB 82-107 285; Cost: $6.50, subject to
change/ will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
U S GOVERNMENT PRINTING OFFICE, 1981 - 559-017/7406
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
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