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Downloaded by UNIV OF MASSACHUSETTS AMHERST on September 12, 2015 | http://pubs.acs.org Publication Date: September 3, 1981 | doi: 10.1021/bk-1981-0163.ch005
Hydrogen Sulfide Evolution from Colorado Oil Shale A. K. BURNHAM, N. KIRKMAN BEY, and G. J. KOSKINAS Lawrence Livermore National Laboratory, University of California, Livermore, CA 94550
Because traditional oil resources are declining, new-found attention is being focused on oil shale, coal, and oil sand as potential supplies of future energy. Unfortunately, extensive use of coal and oil shale could cause severe environmental problems. For example, oil shale retorting produces significant amounts of hydrogen sulfide and other gaseous sulfur species, e.g., 1.3 g H S/100 g shale oil (1). In addition, evolution of H S from oil shale retorted in the presence of steam is greater than in other gas environments (2). In our study, we have measured the dependence of H S evolution on gas atmosphere. The gas environments used were argon, autogenous (self-generated), and steam-argon mixtures, a l l at atmospheric pressure. The samples used in these experiments were Green River oil shale from Colorado. In Green River oil shale, sulfur occurs in both inorganic and organic combinations. According to Smith et al. (3), the Green River oil shale rocks are basically siliceous dolomite that contain varying amounts of organic matter. They suggest that H S was generated by bacterial attack on the organic matter. Pyrite (FeS ) then formed by the low-temperature reaction of iron and H S. Smith et al. (3) and Young (4) have shown that 70 to 85% of the sulfur is present as pyrite; most of the remaining sulfur is present as organic sulfur. The iron sulfide minerals have a median particle size of about 20 μm (5). Atwood et al. (6) found a correlation (r = 0.95) between oil shale grade and pyritic sulfur. During pyrolysis, H S could be formed from the reaction of pyrite with hydrocarbons, hydrogen, or water, and from cracking of organosulfur compounds. Our objective was to determine the importance of these various reactions and to report the amounts of H S evolved from oil-shale samples obtained from locations in Colorado. 2
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0097-6156/81/0163-0061$05.00/0 © 1981 American Chemical Society
In Oil Shale, Tar Sands, and Related Materials; Stauffer, H.; ACS Symposium Series; American Chemical Society: Washington, DC, 1981.
OIL SHALE, TAR SANDS, AND RELATED MATERIALS
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Downloaded by UNIV OF MASSACHUSETTS AMHERST on September 12, 2015 | http://pubs.acs.org Publication Date: September 3, 1981 | doi: 10.1021/bk-1981-0163.ch005
Experimental Sample Preparation and Apparatus. The o i l - s h a l e samples used i n t h i s study were taken from the A n v i l P o i n t s mine, T r a c t C-a, Logan Wash, and the Colony mine. Table I gives the p r o p e r t i e s of the shale samples. The shale samples were crushed and sieved to less than 841 um diam. A p o r t i o n of Sample AP22 was doped with 1 wt% f i n e l y ground (
