Hydrocracking of naphthalene over Beta zeolite coupled with NiMo/γ-Al2O3: Investigation of metal and acid balance based on the composition of industrial hydrocracking catalyst

Abstract

In this work, NiMo/γ-Al2O3 catalysts with the different hydrogenation function were prepared by adjusting the metal composition, while Beta zeolites with the different acidity were synthesized by regulating their Si/Al ratios. The influences of the metal–acid balance on hydrocracking of naphthalene are investigated via coupling the various NiMo/γ-Al2O3 with Beta zeolite (NiMo/γ-Al2O3 + Beta). Compared to NiMo/Beta, NiMo/γ-Al2O3 + Beta displayed the closer catalytic performance in hydrocracking of naphthalene to the catalyst prepared by the method employed in industry, indicating that it is feasible to simulate industrial catalyst through coupling method. The catalytic performance of the coupled catalysts greatly depends on the hydrogenation ability of NiMo/γ-Al2O3 and the acidity of Beta zeolite. The Si/Al ratio, crystal size and amount of the Beta zeolite greatly affect the hydrocracking performance of the coupled catalyst. Ni(2)Mo(13.2)/γ-Al2O3 + Beta(20) exhibited the highest BTX selectivity (62.8%) at 98% naphthalene conversion due to its well-matched hydrogenation and acid function.