Hydrogen spillover effect in hydrocracking catalyst: A TPR study

Hydrogen spillover effect in hydrocracking catalyst was studied using temperature-programmed reduction. A novel method was developed to incorporate a very small amount of precious metal directly on the base metals supported catalyst to enhance the hydrogenation functionality. A marked reduction in the peak temperature was observed by incorporation of precious metal in a relatively small amount. Ni-W supported on alumina reduced at ∼ 586°C. Similar catalyst with Rh incorporated by a novel method produced a large reduction peak at 380°C. Cracking-functionality was modified by changing the acidity of a commercially available USY-zeolite. The acidity was modified by steaming, impregnating with a metal from lanthanide series, and organic acid washing and combination of some of these methods. The effect of acidity modification was studied using cumene cracking. A relationship was observed between the cumene conversion and the acidity of the modified USY-zeolite samples. This is an abstract of a paper presented at the 12th Saudi Arabia-Japan Symposium on Catalysts in Petroleum Refining & Petrochemicals (Dhahran, Saudi Arabia 12/15-16/2002).