Simultaneous liquefaction of a subbituminous coal and upgrading of bitumen with molten ZnCl₂-based catalysts

Molten halide catalysts have been found to have excellent cracking activity towards coal and bitumen-related structures as has been reported in the literature. Upgrading experiments have been carried out in a batch autoclave to study the effectiveness of molten halide catalysts consisting of ZnCl₂ and its mixtures with MoCl₅, on simultaneous liquefaction of a subbituminous coal and upgrading of Athabasca bitumen. Two methods of catalyst addition to the reaction slurry were compared. Impregnation of the coal with a catalyst-saturated methanol solution was found to be more effective than direct addition of the pulverized catalyst. The effects of different variables such as temperature, reaction time, catalyst quantity and catalyst formulations were studied. The optimum temperature and reaction time were found to be 400°C and 2 h respectively. Under these conditions, a net conversion of 75% of the d.a.f. (dry ash-free) coal was achieved.