A novel approach to bulk-phase hydrogenation using an extremely high-loading sulfide NiMoW/SiO2 catalyst

• Extremely high-loading sulfide NiMoW/SiO 2 catalyst were successfully synthesized. • The catalyst demonstrated catalytic properties similar to bulk phase catalysts. • The catalyst demonstrated excellent stability and regenerability. Supported and bulk phase catalysts are both extensively used in hydrogenation reactions, possess distinct strengths and limitations. Aiming to create a catalyst that combines the benefits of both, a series of NiMoW/SiO 2 catalysts were synthesized with varied metal loadings using SiO 2 supports characterized by different pore structures. The catalytic activities of these catalysts were evaluated using 1-methylnaphthalene, dibenzothiophene and quinoline as model compounds. Comprehensive microstructural characterization was performed through ICP-OES, N 2 physisorption, HRTEM, SEM, and XPS techniques. The investigation revealed that both the catalytic and microstructural properties of the catalysts gradually changed from the supported catalysts to the bulk catalysts with the gradual increase of the metal loadings. This transition was accompanied by a significant enhancement in activity and hydrogenation selectivity compare to the supported catalysts. Nonetheless, this catalyst preserved the benefits of a superior pore structure, straightforward preparation methods and excellent regeneration.