CATALYTIC FUNCTIONALITY OF LAYERED MOLYBDENUM DISULFIDE FOR THE HYDRODESULFURIZATION OF DIBENZOTHIOPHENE

摘要

Nanosized transition metal sulfides, an important class of materials which exhibit numerous interesting properties, find potential implement in many applications. For instance, in hydrodesulfurization (HDS) (where S atoms are catalytically removed from petroleum feedstocks), MoS2 based catalysts are considered to be the black horse catalysts for such reactions. The recent environmental regulations that call for sulfur-free fuels are behind the search for potential active catalysts In order to achieve this high sulfur conversion, we need to remove the refractory sulfur-containing compounds, like DBT and its substituted species. Conversion of these species proceeds via two routes, hydrogenation (HYD) and direct desulfurization (DDS). The activity is speculated to be caused by the unsaturated coordinated active sites . It is necessary to understand in detail the structure and nature of the sites for the different HDS routes. Indeed, the structure-activity correlations play important roles in this matter. MoS2 is a layered anisotropic material of various stacking sequences. The particle size of MoS2 has an impact on the catalytic activity and selectivity in the HDS reactions . In the present study, we aim to investigate the HDS of DBT on different nanosized MoS2 catalysts. The correlation between the textural characteristic of MoS2 layers and their catalytic performances for the HDS is discussed.