采用溶胶-凝胶法制备了Co-Mo超细复合氧化物,进而制得了非负载型Co-Mo催化剂;采用XRD、IR、BET、SEM等考察了n(A1):n(Co+Mo)、n(Mo):n(Co+Mo)和CA(柠檬酸)/(Co+Mo)的摩尔比对对应催化剂的表面形貌、结构和催化性能的影响.结果表明:制备的非负载催化剂以β-CoMoO<,4> 物相为主,其晶粒度约为25～35 nm,仅含有L酸;n(A1):n(Co+Mo)、n(Mo):n(Co+Mo)和n(CA):n(Co+Mo)对催化剂的结构、酸类型均无显著影响,但对其比表面积和表面形貌则影响较大.当n(A1):n(Co+Mo)、n(Mo):n(Co+Mo)和n(CA):n(Co+Mo)分别为0.3,0.72和0.89时,制备的催化剂颗粒细小均匀,比表面积较大,其加氢脱硫活性最高.%Co-Mo superfine composite oxides were prepared by a sol-gel method as catalysts. The effects of A1/(Co+Mo), Mo/(Co+Mo) and CA(citric acid)/(Co+Mo) molar ratios on the surface morphology and structure of the corresponding unsupported catalysts were examined using XRD, IR,BET, SEM, and the hydrodesulfurization activity of the catalysts was evaluated. The results showed that the phase of the unsupported catalysts was mainly β-CoMoO4 with the crystal size of about 25 -35 nm; the catalysts only had L acid. The molar ratios of the A1/(Co+Mo), Mo/(Co+Mo) and CA/(Co+Mo) had no significantly influence on the structure and the acid types of the catalysts, but had a greater impact on the surface area and the surface topography. The prepared catalyst with the molar ratios of the A1/(Co+Mo) 0.3, Mo/(Co+Mo) 0.72 and CA/(Co+Mo) 0. 89 had small particle size and higher surface area, and exhibited the highest hydrodesulfurization activity.
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