TiO_2-Al_2O_3复合载体的制备及Co-Mo/TiO_2-Al_2O_3催化剂加氢脱硫性能的研究

通过改进的溶胶-凝胶法(SG)、共沉淀法(CP)、表面沉淀法(PR)及混捏法(ME)制备TiO_2-Al_2O_3复合载体,考察了不同制备方法对复合载体物理性质的影响。采用浸渍法制备Co-Mo/TiO_2-Al_2O_3-X加氢脱硫催化剂,研究了Co-Mo/TiO_2-Al_2O_3-X加氢脱硫催化剂的脱硫性能。利用XRD、BET、SEM等表征手段对复合载体及催化剂进行表征分析。结果表明,SG法制备的复合载体粒径均一,具有较大的比表面积、孔径和孔体积;CP法制备复合载体时TiO_2以单层或亚单层的分散状态高度分散于γ-Al_2O_3中。在氢气压力3.0 MPa、反应温度280℃、反应时间4 h、液时空速1.4 h-1和氢油比600的条件下,SG法制备的Co-Mo/TiO_2-Al_2O_3催化剂具有较高加氢脱硫活性,噻吩转化率达到96.6%。

Study on the preparation of TiO2-Al2O3 composite support and its application in Co-Mo/TiO2-Al2O3 catalyst for hydro-desulfurization

A variety of TiO₂-Al₂O₃ composite support were prepared using improved sol-gel method (SG), co-precipitation method (CP), surface precipitation (PR) and mechanical kneading method (ME), and the influence of preparation methods on their physical properties were investigated. The hydro-desulfurization activity of Co-Mo/TiO₂-Al₂O₃-X catalysts prepared by impregnation method was studied. XRD, BET and SEM were used to characterize the composite support and the catalysts. Results show that the composite support prepared by SG method has uniform morphology with larger surface area, pore size and pore volume. And the monolayer or sub-monolayer of TiO₂ existed in the γ-Al₂O₃. Under the reaction conditions of 3.0 MPa of hydrogen pressure, 280℃ of reaction temperature, 4 h of reaction time, 1.4 h^-1 of the liquid space velocity and 600 of hydrogen to oil ratio, Co-Mo/TiO₂-Al₂O₃ prepared by SG method has highest hydro-desulfurization activity, and the thiophene conversion rate reached 96.6%.