Mineral matter effects and catalyst characterization in coal liquefaction. Annual report, October 1977--September 1978

This is the final report of a study of mineral matter effects in coal liquefaction. The objectives were to: (1) determine the general effects of mineral content on product composition for residence times of 2, 10, and 40 minutes and (2) determine the specific catalytic effects of several iron sulfides on coal conversion and product quality. To study the effects of mineral matter at relatively short residence times, we modified an existing one-liter, stirred, high-pressure autoclave for rapid heating and cooling of a coal/solvent slurry. The rapid heatup experiments were carried out with Illinois No. 6 coal in tetralin solvent, at 410/sup 0/C and 1500 psig. As the residence time increased from 2 to 40 min., the conversion to benzene solubles increased from 25 to 61% and the yield of pentane-soluble oil increased from 13 to 16%. The preasphaltenes increased initially from 31 to 38%, and then decreased to 27%. Addition of pyrite (7 wt % based on coal), at a residence time of 10 min., resulted in an increase in the yield of pentane-soluble oil and a decrease in the yield of asphaltenes and preasphaltenes decreased with increasing residence time. To study the effects of iron sulfides on coalmore » liquefaction, we carried out a series of slow-heatup runs. Naturally occurring pyrite and several different pyrrhotites were used at a concentration, based on coal, of 5.5 wt % iron.« less