Nickel impregnated mesoporous USY zeolites for hydrodeoxygenation of anisole

Abstract

Ni was impregnated on various mesoporous USY zeolites, which were characterized and tested for catalytic hydrodeoxygenation (HDO) of anisole. Parent USY zeolite was modified using the mild surfactant-assisted method, and more severe desilication and desilication with pore directed agent techniques. Ni impregnation on the zeolites with higher micropore volume produced small, easily reduced, internal Ni crystallites, whereas the larger mesopores promoted the formation of bulky external Ni particles. Catalysts with larger external Ni particles were more effective for HDO of anisole. HDO with the optimal mesoporous USY supported catalyst proceeded at more than double the reaction rate, with greater yield to fully deoxygenated products, compared to HDO using Ni supported on the parent USY. Kinetic modeling using a simple lumped mechanism demonstrated that this improvement was a result of greater rates of initial Ni-catalyzed hydrogenation reactions, most likely due to greater access to the Ni surface. The most successful technique was further modified to produce a final mesoporous USY supported Ni zeolite with superior catalytic activity for anisole HDO.