Dependence of Morphology, Dispersion and Hydrodesulfurization Performance of Active Phases in NiMo/SBA‐15 on Loading Method

Abstract

AbstractWith the aim of exploring the dependence of morphology, dispersion and hydrodesulfurization (HDS) activity of active phases over SBA‐15 on loading method, four NiMo/SBA‐15 catalysts have been prepared by two different Mo introduction strategies with varying MoO3 contents (13 and 19 wt.% in each approach, respectively). One of the approaches is the conventional incipient wetness impregnation (IM) and the other is a new‐proposed Mo‐based inorganic‐organic hybrid nanocrystals as the precursor with hydrothermal‐assisted (HA) loading method. The results show that metal species are severely aggregated at a high concentration by IM method, leading to the poorly distributed MoS2 slabs with large sizes and ultra‐high stacking layers. While in case of the HA approach, the organic molecules surrounding the Mo species can isolate Mo species effectively to prevent them from aggregation and greatly improve the dispersion of active phases, even at high MoO3 loadings. Therefore, the HDS activity is improved as increasing the amounts of MoO3 for the catalyst prepared with HA method because of the more active sites accessible to the reactants, however, HDS activity is decreased for the catalyst acquired by the IM method due to the serious metal aggregation. It is demonstrated that the HA method is favorable for the better dispersion of active phases over SBA‐15 with the help of organic molecules leading to the effective MoS2 morphology with remarkably enhanced catalytic activity, and such superiority of the HA approach is more prominent at high MoO3 loadings.