v°/EPA
United States
Environmental Protection
Agency
Municipal Environmental Research
Laboratory
Cincinnati OH 45268
Research and Development
EPA-600/S2-81-032 Mar 1981
Project Summary
Biodegradation and Carbon
Adsorption of Carcinogenic
and Hazardous Organic
Compounds
E. G. Fochtman
This research program was con-
ducted to determine the capability of
biological treatment and activated
carbon adsorption to remove chemical
carcinogens and other hazardous
organic compounds from water and
wastewater. All of the 11 compounds
tested exhibited some degree of bio-
logical degradation. Carbon adsorp-
tion was also effective in removing the
compounds from aqueous solution.
Analytical methods were adapted to
analyze the very insoluble polynuclear
aromatic hydrocarbons that tenaciously
adsorbed on the glass surfaces of
sample bottles and analytical glass-
ware.
This Project Summary was devel-
oped by EPA's Municipal Environmen-
tal Research Laboratory, Cincinnati,
OH to announce key findings of the
research project which is fully docu-
mented in a separate report of the
same title (see Project Report ordering
information at back).
The carbon adsorption isotherms and
the ease of biodegradation were deter-
mined experimentally for 11 organic
compounds selected from EPA's Priority
Pollutant List and OSHA's List of Regu-
lated Carcinogens. Because of the
hazards presented by the compounds,
special laboratory procedures were
followed when handling them. In addi-
tion, the low solubility of the compounds
and the tendency of some of them to
adsorb on laboratory glassware required
developing procedures for solution
preparation and sampling handling.
The study was conducted in laboratory
facilities designed for the handling of
highly toxic or carcinogenic chemicals.
All laboratory personnel were under
medical surveillance.
Carbon adsorption isotherms were
determined by treating an aqueous
solution of known concentration and
volume with a known weight of granular
activated carbon that had been ball
milled to less than 325 mesh. The low
solubility of most of the compounds,
generally less than 1 ppm, made it very
difficult to prepare aqueous solutions
free of undissolved chemical particles.
In the procedure developed, water was
pumped through a bed of beads coated
with the chemical, then filtered to
remove the particles of undissolved
chemical.
Several of the chemicals rapidly and
tenaciously adsorbed on the glass sur-
faces of sample bottles, glass fiber
filters, filter flasks, and analytical glass-
ware. Such adsorption was minimized
by withdrawing the aqueous sample
and mixing it with methyl alcohol to give
40 percent alcohol in the final sample.
Only very small amounts of carbon were
required, generally 1 mg/L of solution.
The carbon was allowed to settle for 1
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hour before a sample was withdrawn
from the top of the container.
Biodegradation was determined using
a static procedure. An approximately 1 %
solution of the chemical in an emulsif ier
was added to a bacterial suspension at
concentration levels of 1 to 2 ppm. The
suspension was analyzed twice: imme-
diately after preparation and after a 7-
day incubation period. Fresh bacterial
suspension was prepared weekly using
seed from the previous week. The
procedure was continued for 28 days.
Analytical procedures varied depend-
ing upon the characteristics of the
chemical and the type of sample. Neat
samples were analyzed by ultraviolet
absorption or fluorescence. Biological
samples were extracted, concentrated,
and analyzed by a liquid chromatograph
equipped with a solvent programmerfor
gradient elution and an ultraviolet
absorption detector.
Data have been presented as Freundlich
adsorption isotherms expressed as:
*_= KCf1 '"
M
where
X = Co - C,
C0 = concentration of organic
in untreated solution
Cf = concentration of organic
in treated solution
M = concentration of carbon
K = empirical constant
1/n = empirical constant
K is the intercept of the plot of the
isotherm at C< = and 1 /n is the slope of
the line on logarithmic paper.
Data for the compounds studied are
given in Table 1.
All of the compounds exhibited
some degree of biological degradation.
Typical values for percent removal
during a 7-day incubation are given in
Table 2.
More detailed information, including
experimental data and laboratory pro-
cedures, can be found in the complete
project report, available through the
National Technical Information Service
(NTIS). The full report was submitted in
fulfillment of Contract No. 68-03-2834
by NT Research Institute under the
sponsorship of the U.S. Environmental
Protection Agency.
Table 1. Freundlich Parameters and Capacity of GAC
Freundtich
Parameters
Compound
Benzidine
3, 3 '-Dichlorobenzidine
Benzo(a)pyrene
2 -A cetylaminofluorene
4-Aminobiphenyl
4-Dimethylaminoazobenzene
4 -Nitrobiphen yl
Benzofg, h, ijperylene
Dibenzo(a, hfanthracene
Benzo(k)fluoranthene
3. 4-Benzofluoranthene
Mo/
wt
184
253
252
222
169
225
199
276
278
252
252
pH
9.1/7.1
7.2
7.1
7.1
7.2
7.0
7.0
7.0
7.1
7.1
7.0
K
215
308
34
318
198
250
370
10
70
183
56
1/n
0.16
0.19
0.44
0.12
0.26
0.24
0.27
0.36
0.76
0.67
0.37
Corral
Coefl
0.966
0.968
0.905
0.944
0.965
0.959
0.978
0.923
0.970
0.983
0.946
No
of
Data
Points
16
8
6
7
9
8
6
8
8
8
8
Calculated
mgC/L
to reduce
1 0 mg/L
to 0 1 mg/L
6
5
0.4
3.8
8
6.2
4.5
197
73
18
0.5
Table 2. Biological Degradation
Percent
Compound Degraded
Benzofajpyrene 41
2-Acetylaminofluorene 14
4-Aminobiphenyl 50
4-Dimethylaminoazobenzene 99+
4-Nitrobiphenyl 99+
Benzo(g,h,ijperylene 60
Dibenzo(a,h)anthracene 60
Benzo(k)fluoranthene 54
E. G. Fochtman is with the IIT Research Institute, Chicago, IL 60616.
Richard A. Dobbs is the EPA Project Officer (see below)
The complete report, entitled "Biodegradation and Carbon Adsorption of
Carcinogenic and Hazardous Organic Compounds," (Order No PB 81-171 852;
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:
Municipal Environmental Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
•: US GOVERNMENT PRINTING OFFICE 1981 -757-01Z/7053
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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