Supported Nickel Molybdenum Sulfide Hydrocracking Catalysts Profit From Increased Proximity Between Acid and Metal Sites in the Tetralin Ring‐Opening Performance

ABSTRACT Mo‐modified HY zeolite‐alumina composites, featuring closely adjacent metal and acid sites, were rationally designed as supports for the preparation of NiMo‐catalysts. These catalysts demonstrate excellent selectivity toward ring‐opening products during tetralin hydrocracking. Mo‐modified HY zeolite (MoHY) samples were initially prepared using both solid‐state ion exchange (SSIE) (designated as MoHY‐S) and the conventional impregnation method (designated as MoHY‐I). Raman and x‐ray photoelectron spectroscopy (XPS) results revealed a lower dispersion of Mo oxides on the zeolite surface of MoHY‐S compared to MoHY‐I. After extrusion with an Al 2 O 3 binder and subsequent sulfidation, a greater number of (Ni)MoS 2 nanoslabs, acting as active sites for hydrogenation reactions, were observed on the zeolite surface of the NiMo/(Al 2 O 3 +MoHY‐S) catalyst compared to those of the NiMo/(Al 2 O 3 +MoHY‐I) and reference NiMo/(Al 2 O 3 +HY) catalysts. Further evaluation of tetralin hydrocracking performance revealed that the NiMo/(Al 2 O 3 +MoHY‐S) catalyst exhibited the highest activity and ring‐opening selectivity, accompanied by the lowest level of secondary cracking among the three catalysts. This superior performance is attributed to the enhanced dispersion of metal sites in close proximity to the acid sites of HY zeolite. Notably, strengthening the proximity between acid and metal sites can effectively promote the synergy between the hydrogenation and cracking sites.