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Sciences: Washington, D.C., 1978; pp 476-487. Boehm, P. D.; Fiest, D. L. Environ. Sci. Technol. 1982,16, 67-74. Boehm, P. D.; Fiest, D. L. “Subsurface water column transport and weathering of petroleum hydrocarbons during the IXTOC I blowout in the Bay of Campeche and their relation to surface oil and microlayer compositions”; In “Proceedings of Symposium on the Preliminary Findings of the Researcher Cruise to the IXTOC I Blowout”; NOAA/OMPA Rockville, MD, 1980. McAuliffe, C. D.; Canevari, G. P.; Searl, T. D.; Johnson, J. C. “The Dispersion and Weathering of Chemically Treated Crude Oils on the Sea Surface”; In “Proceedings International Conference and Exhibition; Petroleum on the Marine Environment”, Monaco, May 27-30, 1980. Zurcher, F.; Thuer, M. Environ. Sci. Technol. 1978, 12, 838-843. Boehm, P. D.; Quinn, J. G. Mar. Poll. Bull. 1975,5,101-105. McAuliffe, C. J. Phys. Chem. 1966, 70, 1267-1275. Eganhouse, R. P.; Calder, J. A. Geochim. Cosmochim. Acta 1976,40, 555-561. Sutton, C.; Calder, J. A. Environ. Sci. Technol. 1974, 8, 654-657. Sutton, C.; Calder, J. A. J . Chem. Eng. Data 1975, 20, 320-322. Mackay, D., Paterson, S., Eds. “Oil Spill Modeling”, Proceedings of a workshop held in Toronto, Canada, November 7-8 1978, Publication EE-12; Institute for Environmental Studies: University of Toronto, Toronto, Canada, 1978. Leinonen, P. J.; Mackay, D. ”Mathematical model of the behavior of oil spills on water with natural and chemical dispersion”; prepared for Fisheries and Environment Canada and published as Economic and Technical Review Report No. EPS-3-EC-77-19, 1977. Mackay, D.; Buist, I.; Mascarenhas, R.; Paterson, S. “Oil spill processes and models”; Report to the Environmental
Protection Service (Arctic Marine Oil Spill program) D-SS Contract No. 0655-KE304-8-0680, 1979. Kolpack, R. L.; Plutchak, N. B. In “Proceedings of Symposium on Sources, Effects and Sinks of Hydrocarbons in the Aquatic Environment”, August 9-11 1976, Keystone, CO, American Institute for Biological Sciences, Washington, D.C. Mattson, J. S.; Grose, P. L. ”Modeling algorithms for the weathering of oil in the marine environment”, Final Report, Research Unit No. 499, Outer Continental Shelf Environmental Assessment Program; NOAA: Boulder, CO, 1979. Harrison, W.; Winnik, M. A.; Kwong, P. T. Y.; Mackay, D. Environ. Sci. Technol. 1975, 9, 231-234. Yang, W. C.; Wang, H. Water Res. 1977,11,879-887. Garrett, W. D. Limnol. Oceanogr. 1965, 10, 602-605. Gagosian, R. B.; Dean, J. P., Jr.; Hambun, R.; Zafiriou, 0. C. Limnol. Oceanogr. 1979,24,583-588. Boehm, P. D. Mar. Chem. 1980,9, 255-281. Boehm, P. D.; Barak, J. E.; Fiest, D. L.; Elskus, A. Mar. Environ. Res. 1982, 6, 157-188. Larson, R. A.; Bott, T. L.; Hunt, L. L.; Rogenmuser, K. Environ. Sci. Technol. 1979, 13, 965-969. Atlas, R. M.; Boehm, P. D.; Calder, J. A. Estuarine Coast. Mar. Sci. 1981, 12, 589-608. Mackay, D.; Matsugu, R. S. Can. J. Chem. Eng. 1973, 5, 434-439. Cohen, Y.; Mackay, D.; Shiu, W. Y. Can. J. Chem. Eng. 1980,58, 569-575. Boehm, P. D.; Mackay, D.; Fiest, D. L.; Paterson, S., to be submitted for publication.
Received for review November 6,1981. Accepted April 16,1982. This research was supported by Research Contract No. NA80RAC0054 from the Nationql Oceanic and Atmospheric Administration, Office of Marine Pollution Assessment.
Lipid-Soluble Metal Compounds in a Coal Gasifier Process Stream Alan R. Dahl” and Suzanne H. Welssmant
Lovelace Biomedical and Environmental Research Institute, Albuquerque, New Mexico 87 185
rn The concentrations of iron, chromium, zinc, and aluminum were measured by atomic absorption spectroscopy in the lipid-soluble fractions of tar from the process stream of an experimental coal gasifier as part of a larger study on the health risks of coal gasification. Lipid solubility was inferred from octanol/water-partitioning and benzene-solubility tests. The properties of the lipid-soluble metals were compared to reference compounds by Sephadex LH-20 chromatography. The ability of the lipidsoluble metals to remain lipid soluble after treatment with acid and base was also tested. Lipid-soluble iron, chromium, zinc, and aluminum were present at 360,12,3, and 1 ppm, respectively, in the gasifier coal tar. The presence of these metals in lipid-soluble form may have important consequences relative to the potential toxicity of the tar if persons are exposed to it. Introduction The presence of lipid-soluble metal compounds in coal gasifier process streams has been postulated on theoretical grounds (1). Lipid-soluble metal compounds include organometallics, metal carbonyls, and chelated metal complexes. Such compounds are of interest because they are Current address: Sandia National Laboratories, Albuquerque, NM 87185. 0013-936X/82/0916-0505$01.25/0
physically and toxicologically quite different from lipidinsoluble forms of the same elements. They are often more toxic than purely inorganic compounds of the same elements (2). The Lovelace Inhalation Toxicology Research Institute (ITRI) and the Morgantown Energy Technology Center (METC) are collaborating on an investigation of the potential health risks of low-Btu coal gasification. A major objective is to chemically and toxicologically characterize materials in the process and effluent streams of the lowBtu gasifier. Results on the characterization of gasifier process stream material for lipid-soluble metal compounds are presented in this paper. Additional reports on the chemical (3-7) and toxicological (6-8) characterization of these materials are available. We have identified and quantitated iron, chromium, zinc, and alminum in lipid-solublefractions of coal gasifier tar. Trace amounts of lipid-soluble lead and nickel were also found. Elucidation of the chemical nature of these compounds included investigation of acid stability and partial characterization by Sephadex LH-20 chromatography.
Experimental Section Instrumentation. Atomic absorption spectroscopy (AAS) was used for determination of metals. Spectrom-
0 1982 American Chemical Society
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Flgure 1. Schematic diagram of the experimental gas cleanup on the Morgantown Energy Technology Center low-Btu gasifier. Samples analyzed in the work presented here were from the tar trap.
eters used were a Perkin-Elmer Model 306 with an airacetylene flame and an Instrumentation Laboratory Model 951 with a Model 555 graphite furnace and a Model 254 Fastac autosampler. Organometallic reference compounds (ferrocene, ferrocene dicarboxylic acid, benzenechromium tricarbonyl, and zinc 2,4-pentanedionate, Alpha Chemical Co.) and inorganic standard solutions (Banco, Anderson Labs, Fort worth, TX, 1000 ppm) were used to determine recovery and measurement efficiencies. All glassware was acid washed with Nochromix (Godax Labs, New York) in sulfuric acid (Baker Analyzed Reagent). Solvents were Burdick and Jackson UV grade (Muskegan, MI) unless otherwise indicated. Water was purified in a Millipore water-purification system. The solvents and glassware acid rinses were analyzed for each metal of interest by using flame AAS; none were detected. Neither Fe nor Zn were detected with furnace AAS. Coal Tar Samples. Tar samples were obtained from the tar trap of the Morgantown Energy Technology Center (METC) experimental coal gasifier (Figure 1). The METC gasifier is a pressurized version of the McDowell-Wellman (Wellman-Galusha) atmospheric pressure stirred-bed gasifier previously described (3). This gasifier uses the Lurgi process for low-Btu coal gasification. I t differs from commercial fixed-bed producers with respect to its smaller size (1.1m id.) and various provisions for stirring the bed. The composition of gas produced was 1 5 2 0 % CO, 5-15% C02, 55-60% N2, 10-15% H2, and
