Design of improved hydrocracking catalysts by increasing the proximity between acid and metallic sites

A new approach was undertaken to increase the bifunctionality of USY zeolite based catalyst. Nickel metallic phase was first impregnated onto USY zeolite and composite catalysts NiMo/[γ-Al2O3 +(Ni)/USY] were prepared from these zeolites. Catalytic properties in toluene hydrogenation and squalane (2,6,10,15,19,23-hexamethyltetracosane) hydrocracking (HCK) were investigated. Enhanced conversion and middle distillate (MD) selectivity was obtained for catalysts on which nickel has been impregnated on the zeolite powder. These enhancements are ascribed to an increased proximity between the hydrogenation/dehydrogenation (H/DH) function and the acid sites resulting in a more efficient synergy between these two functions.