A contmuous-flow drfferenhal reactor was used to obtam rate equatrons for the reachon of throphene and hydrogen over coal mtueral matter and a commercral cobalt-molybdate catalyst (Nalcomo 471) Coal mmeral matter m Its least altered state was obtamed by low temperature ashmg of Western Kentucky # 9 and # 11 coals m an oxygen plasma Conversron was detemuned from the Cq gases separated by gas chromatography Pretreatment of both coal mineral matter and catalyst with hydrogen sulfide increased throphme reactron rates consrderabiy, but mtroductron of the gas wrth reactants markedly decreased the rate All hquefactlon processes under development, cataly& or noncatalmc, add hydrogen to coal contammg mmeral matter Yavorsky et al [l] were the first to speculate that coal mmeral matter was bchavmg as a catalyst durmg hquefaction Hydrocrackmg, Isomenzation, hydrogen transfer, hydrogenation, and hydrodesulf-bon (HDS) are some of the prunary reactions that take place The purpose of thus study was to compare quantitatively the catalytx activity of a commercial HDS catalyst that has been used m coal hquefactlon w&h that of mmeral matter from Western Kentucky coals The reaction chosen was the HDS of tiophene whch serves as a model coal-sulfur compound Gluskoter [2] mtroduced low-temperature ashmg for recovery of coal mmeral matter m Its least altered state Thus method represented a breakthrough m coal charactenzation, and most of the work with low temperature ash (LTA) has been focused m this area By X-ray mractlon, Rae and Gluskoter[3] ldentied pyrite, calcite, kaohmte, and other clay minerals as the prmclpal constituents of LTA produced from 65 Iihnols Basm coals Smce clays were the first crackmg catalysts used in the petroleum