【摘要】 采用溶胶凝胶(sol-gel)、共沉淀(CP)和沉积沉淀(DP)法制备了介孔T iO2-A l2O3复合载体(简称复合载体);以噻吩加氢脱硫(HDS)为探针反应,考察了复合载体的制备方法对负载型Au-Pd催化剂噻吩HDS反应性能的影响;并采用X射线衍射、程序升温还原、程序升温脱附、红外光谱、BET法对复合载体及负载型Au-Pd催化剂进行表征。实验结果表明,CP,DP,sol-gel法都可制备出介孔复合载体,其中,sol-gel法制得的T iO2-A l2O3(S)复合载体的比表面积和孔体积最大。复合载体负载Au-Pd所制备的催化剂具有较高的噻吩HDS活性,其中,Au-Pd/T iO2-A l2O3(S)催化剂的活性最高。Au-Pd/T iO2-A l2O3(S)催化剂中AuxPdy合金的晶粒较小、含量较高,且催化剂的总酸量较多,活性组分的分散度和活性比表面积较大,催化噻吩HDS反应的表观活化能较低。更多还原

【Abstract】 Mesoporous TiO₂-Al₂O₃ composite supports were prepared by coprecipitation（CP）,deposition-precipitation（DP）and sol-gel methods separately.Influences of preparation conditions on activities of supported Au-Pd bimetal catalysts for thiophene hydrodesulfurization（HDS）as probe reaction were studied.Prepared samples were characterized by means of XRD,TPD,TPR,IR and BET.All these composite supports belonged to mesoporous materials.The specific surface area and pore volume of composite supports prepared by sol-gel method（TiO₂-Al₂O₃（S））were the largest.Au-Pd/TiO₂-Al₂O₃ catalysts with supports prepared by different methods were high in HDS activity,among which the activity of Au-Pd/TiO₂-Al₂O₃（S）was the highest.HDS activities of catalysts correlated with the content of Au_xPd_y alloy in catalysts.Au-Pd/TiO₂-Al₂O₃（S）catalyst had smaller Au_xPd_y crystal size,larger active specific surface area,better active component dispersion,more Au_xPd_y alloy content and more acid sites.Apparent activation energy of HDS catalyzed by Au-Pd/TiO₂-Al₂O₃（S）was low.All of above-mentioned factors were favorable to enhancement of catalyst activity.更多还原