The role of nanobeta zeolite in NiMo hydrotreating catalysts

Hydrotreating catalyst NiMo/Al2O3 was modified by adding nano-sized zeolite beta and by hydrothermal treatments. The catalysts were characterized by BET, XRD, Pyridine-IR, 29Si NMR, 27Al NMR and TEM. The results showed that the addition of nanobeta could significantly enhance the hydrodesulfurization (HDS), hydrogenation, and hydrocracking abilities of the NiMo catalysts. The catalytic performance decreased in the order NiMo(C) > NiMo(15) > NiMo(D) > NiMo(7.5) ≫ NiMo/Al2O3. The presence of nanobeta could strengthen acid sites which facilitated the abilities of hydrocracking and removal of sulfur-containing compounds, especially those of refractory nature. Introduction of nanobeta could also induce the synergetic effect between NiMoS and the support material with thicker NiMoS slabs. This morphology change might be responsible for the improvement in hydrogenation. It was observed that hydrothermal treatment conditions could affect the acidity and the NiMoS morphology of the catalysts, which in turn alter the catalyst hydrogenation ability.

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► The role of nanobeta zeolite in NiMo/Al2O3 catalysts was investigated in this study.
► Adding nanobeta zeolite can enhance catalyst acidity and induce new Brønsted acid sites.
► Incorporation of nanobeta zeolite can modify the morphology of NiMoS slabs.
► The HDS and HDN activity of NiMo catalyst can be improved with introduction of nanobeta zeolite.