Advanced direct coal liquefaction concepts. Quarterly report, October 1, 1993--December 31, 1993

Abstract

Six runs on the bench unit were successfully completed this quarter. The runs covered twenty five different operating conditions and yield periods, and involved 336 hours of operation. In the bench unit, increased temperature of first stage operation (410{degree}C) and direct addition of the powdered solid sodium aluminate to the feed as first stage catalyst improved both coal and carbon monoxide conversion. To achieve 90%+ overall coal conversion, temperatures of 430{degree}C+ were required in the second stage. Oil yields (pentane soluble liquid product) in excess of 65 wt % based on MAF Black Thunder coal, were achieved both with iron oxide/dimethyl disulfide and ammonium molybdate/carbon disulfide second stage catalysts. C{sub l}-C{sub 3} hydrogen gas yields were modest, generally 7-8 wt % on MAF coal, and overall hydrogen consumption (including first stage shift hydrogen) was in the order of 7-8 wt % on MAF coal. The ammonium molybdate catalyst system appeared to give slightly higher oil yields and hydrogen consumption, as was expected, but the differences may not be significant.