Controllable assembly of NiMo nano-wool shell on zeolite Y and its advanced behavior of hydrodesulfurization toward dibenzothiophene

A core-shell structured USY-xTT@NiMo catalyst was prepared through thermal treatment method and evaluated for the catalytic hydrodesulfurization (HDS) performance toward dibenzothiophene (DBT). The shell assembled from NiMoS nano-wool provided abundant active site. This nano-wool morphology and core-shell structure resulted in the catalyst with enhanced specific surface area, pore volume, lower interaction between the support and active metals, and facilitated metal dispersion. In addition, the nano-wool morphology and core-shell structure also promoted the degree of sulfurization and provided more sulfur vacancies, which enhanced the HDS performance of the corresponding catalysts. An efficient USY-16TT@NiMo catalyst with shorter slab lengths (average 2.50 nm), higher average stacking number (3.37 layers), and more edge active sites was assembled, which showed superior k_HDS value of DBT up to 8.29 × 10⁻⁴ mol g⁻¹ h⁻¹ and high direct desulfurization selectivity to be 88 %.