HYDRODESULFURIZATION AND HYDRODENITROGENATION OF COAL LIQUID ON NICKEL-MOLYBDENUM CATALYST SUPPORTED ON ALUMINA MODIFIED WITH PHOSPHATE ANDSULFATE-IONS

A series of nickel-molybdenum catalysts incorporated on alumina modifi ed with sulfate and phosphate ions was studied. Decomposition of isopr opyl and diacetone alcohols and ethylbenzene and hydrofining of coal l iquid were used as test reactions. The effect of support modification with phosphate and sulfate ions on the activity of NiMo varied. Incorp oration of these ions at the concentrations used led to a decrease in acidity of the catalyst surface which increased with increasing concen tration of the modifier. Phosphate ions raised the dehydrogenation act ivity, whereas sulfate ions hardly affected it. Both ions caused a sig nificant decrease in HDN activity for coal liquid which diminished wit h increasing concentration of the ions. They also caused a slight decr ease in HDS activity which however did not depend on their concentrati on. (C) 1997 Elsevier Science Ltd.