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Catalyst samples from Wilsonville runs 242, 246, 247, and 248 have been characterized and tested for hydrodesulfurization activity in order to determine the effects of different process configurations and coals on the causes and rates of deactivation. Initial rapid decreases in activity were caused by the accumulation of carbonaceous deposits within the catalyst. Variations in the amount of deposition were due to the process configuration but not the coal type. The process configuration with the most preasphaltenes and unconverted coal in the hydrotreater feed yielded the greatest buildup of carbonaceous deposits and the most deactivation. After the initial high losses, the activities continued to decrease with catalyst age due to the accumulation of contaminant metals in the catalyst. The rates of contaminant metals buildup varied significantly from run to run. Deactivation by carbonaceous deposits and contaminant metals was due to both poisoning of active sites and decreases in effective diffusivities. In addition, sintering of the active metals was observed in the aged catalysts.

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A group of hydrous oxide ion-exchange compounds which can be used to prepare hydrogenation catalysts by a novel synthesis route has been identified. These materials offer several advantages for catalyst formulation, including high surface area, dispersion of any metal or mixture of metals and promoters over a wide concentration range, and adjustment of substrate acidity as well as active metal oxidation state. Catalysts prepared by exchanging the sodium ion of sodium hydrous titanate for Ni, Mo, and Pd were tested for use in direct coal liquefaction. Results of hydrogenation experiments performed with the addition of the catalysts to a slurry of a bituminous coal in a coal-derived solvent demonstrated that hydrous titanate catalysts with active metal loadings as low as 1 % were equally effective for liquefying coal as a commercial NI-Mo/alumina catalyst containing 15% by weight active metals.

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