Synthesis and Performance of Presulfided NiMoP/Al2O3-SiO2 Catalyst

Abstract

Presulfided NiMoP/Al2O3-SiO2 catalysts were synthesised. The BET surface area and BJH pore volume gradually decrease with P loading due to the ingress of active phases into the pores of the support. No bulk Ni sulfide phase is observed either in the XRD pattern or in the HRTEM micrographs of all catalysts. The mainly high active center is multilayered Ni-Mo-S type II phase benefited from the weak bond between Al2O3-SiO2 support and active components. The incorporation of phosphorous enhances the dispersion of MoS2 particles and formed more multilayered Ni-Mo-S type II phase. The route of hydrogenation activity increases with the content of P up to 1.2 wt.%, and the route of direct desulfurization activity in the hydrodesulfurization of dibenzothiophene decreases simultaneously. This is attributed to the higher MoS2 stacking number and shorter MoS2 slab length.