Sulfided Mo/Al2O3 hydrodesulfurization catalyst prepared by ethanol-assisted chemical deposition method

Abstract

In this communication, we report a novel strategy to prepare a MoS2/Al2O3 hydrodesulfurization (HDS) catalyst by thermally treating a MoS3/Al2O3 precursor in H2 atmosphere. In our approach, the active phase precursor MoS3 was first prepared using thioacetamide and sodium molybdate as sources of S and Mo, respectively, and ethanol as a dispersant. The precursor was deposited onto the surface of a γ-Al2O3 support and heat-treated to form the catalyst. The catalyst was characterized by N2 adsorption-desorption, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. The HDS activity of the catalyst was assessed using dibenzothiophene as a model reactant. The catalyst possessed larger specific surface area and pore volume, higher dispersion and degree of sulfidation of Mo species, and shorter and more suitable stacking of MoS2 slabs, resulting in superior catalytic activity compared with a catalyst with the same metal content prepared by the conventional impregnation method. Ethanol could disperse the precursor MoS3 particles via “S…H-O” H-bonding to lessen their aggregation. 以硫代乙酰胺为硫源, 14;钼酸钠为钼源, 14;乙醇为分散剂, 14;采用化学沉积法制备了MoS3/Al2O3催化剂前驱体, 14;再用H2高温处理得到高分散硫化型MoS2/γ-Al2O3催化剂, 14;运用N2吸附-脱附、X射线光电子能谱以及高分辨透射电子显微镜等技术对MoS2/γ-Al2O3催化剂进行了表征, 14;并以二苯并噻吩作为模型化合物评价了催化剂的加氢脱硫(HDS)活性. 结果表明, 14;与浸渍法相比, 14;所制催化剂具有更大的比表面积和孔体积、更高的活性金属分散度、更佳的Mo物种硫化度以及更短的MoS2片层长度和更高的堆积度, 14;因而在二苯并噻吩HDS反应中表现出远优于浸渍法所制催化剂的活性. 乙醇可通过S…H-O氢键吸附至MoS3纳米粒子表面, 14;可有效防止其生长和团聚, 14;起到分散剂的作用. 14