NiW catalyst modified with C12A7-H− and its promotion to hydrogenation selectivity of hydrodesulfurization

Abstract

[Ca24Al28O64]4+·4(H−) (abbreviated as C12A7-H−) powder containing H− species was synthesized to modify NiW catalyst. The incorporation of C12A7-H− increases the reaction rate constants and turnover frequencies of NiW catalysts in hydrodesulfurization (HDS) of dibenzothiophene (DBT). The characterization results show that the introduction of C12A7-H− promotes the reducibility of NiW catalysts, resulting in higher sulfidation degree and more Ni-W-S species. In spite of the fact that rim/edge sites ratios and Lewis acid sites are decreased, the introduction of C12A7-H− still increases the hydrogenation/direct desulfurization ratios of NiW catalysts in HDS of DBT. Furthermore, higher HDS rates of C12A7-H− modified NiW catalysts are also observed in HDS of 4,6-dimethyldibenzothiophene. These can be attributed to C12A7-H− material that may transfer active H species to NiW catalysts and thereby promote the hydrogenation selectivity of NiW catalyst.