关键词: 选择性加氢脱硫, 硫醇硫, 催化剂, Ce改性

Abstract: To investigate the physicochemical properties and catalytic performance for mercaptan sulfur formation in selective hydrodesulfurization, Ce modified CoMo/Al2O3 catalysts were prepared. The catalysts were characterized by XRD， H2-TPR， Py-IR， XPS and HRTEM, and the catalytic performance was evaluated in a continuous flow fixedbed microreactor. Results show that Ce species are in the form of Ce3+ on the surface of supporter, as CeAlO3 or similar structures. The introduction of Ce weakens the interaction between the active component and supporter, thus improving the dispersion of Mo species on supporter. The catalyst with suitable content of CeO2 favors the sulfidation of Mo species in the pre-sulfidation process, which promotes the formation of coordinative unsaturated sites (CUSs) and then increases Lewis acid amount of sulfide catalyst. Average slab length and stacking layer number of MoS2 slabs are moderately increased， thereby promoting the formation of type II CoMoS phase. Catalysts with Ce modification exhibit poor activity for mercaptan sulfur formation. Mercaptan sulfur formation performance of catalysts is correlated to the content of CoMoS phase and the amount ratio of strong Lewis acid to weak Lewis acid (A(Ls)/A(Lw)). The mercaptan sulfur content in product is decreasing and the content of CoMoS is increasing along with the raising of (A(Ls)/A(Lw)).

Key words: selective hydrodesulfurization, mercaptan sulfur, catalyst, Ce modification