An extensive infrared investigation of the CO/Rhl AI,OJ system has revealed the presence of eight different CO/Rh species including two which have not been observed previously. It has been shown that Rh loading on an alumina support is more critical than reduction temperature in effecting infrared spectral changes in the 1800-2200 cm -\ region. The oxidation state of Rh for the various CO/Rh species has been discussed; it has been postulated that for several of the species the oxidation state of Rh is greater than 0. Furthermore, this work indicates that there is significant atomic dispersion on Rhl AI,OJ catalysts prepared from RhCI J ·3H,OI AI,OJ by a procedure described originally by Yang and Garland. These catalysts retain appreciable amounts of chlorine even following hydrogenation at 673 K.

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Coprocessing coal with waste oil can achieve the dual purpose of recycling waste oil and liquefying coal economically. Waste oil is primarily paraffinic and is a poor hydrogen donor solvent but contains dispersant additives which could help improve dispersion of the coal particles and the catalysts during liquefaction. The initial coprocessing studies were conducted using 10 % coal in tubing bomb reactors and a jet-loop reactor system developed at Auburn University. Coal conversions in excess of 85 % were obtained during coprocessing with selectivity of over 80 % to oils. The use of iron-based catalyst precursors and a traditional hydrogen donor solvent such as tetralin with waste oil did not have a significant effect on conversion and selectivity during coprocessing. However, the sulfur removal and the ash removal from the waste oil increased. This study indicates that coprocessing coal with waste oil is beneficial, and an extensive study is under way at present.

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The purpose of this study was to demonstrate that certain coal minerals catalyze the hydrogenation and hydrodesulfurization of creosote oil, a coal-derived solvent used as a start-up solvent In the Solvent Refined Coal (SRC) process; to show that by accelerating hydrogenation of a process solvent such as creosote oil, coal mineral catalysis accelerates Indirectly the rate of liquefaction of coal solids; and to provide better insight as to the process advantages and disadvantages of utilizing coal mineral catalysis. Several major constitutents of coal mineral matter have been examined for possible catalytic effects in the reactions of hydrogenation and hydrodesulfurization In coal liquefaction processes. Certain coal minerals, particularly those containing iron, were found to cataylze both hydrogenation and desulfurization reactions. The rate-limiting step in the liquefaction of coal appears to be the transfer of hydrogen to an appropriate donor solvent, and consequently the rate of liquefaction increases with the concentration of coal minerals. The physical state, as well as chemical composition, of the coal minerals also affects hydrogenation and hydrodesulfurization activity during coal liquefaction. Coal mineral catalysis of reactions occurring in coal conversion processes may or may not be advantageous, depending on process objectives and on composition and state of the coal minerals present.