【摘要】 采用溶胶-凝胶法制备了介孔TiO2-Al2O3复合氧化物载体,考察了载体的焙烧温度对负载型Au-Pd双金属催化剂加氢脱硫性能的影响,并采用X射线衍射、吸附吡啶的程序升温脱附、程序升温还原、红外光谱和N2物理吸附等技术对载体及催化剂进行了表征.结果表明,不同温度焙烧的TiO2-Al2O3复合载体都具有介孔结构,其中773 K焙烧制得的TiO2-Al2O3复合载体的比表面积和孔容较大,B酸中心较多,以其为载体的Au-Pd催化剂具有较好的加氢脱硫活性.表征结果表明,773 K焙烧制得的Au-Pd/TiO2-Al2O3催化剂中Au-Pd活性组分与载体的相互作用较强,催化剂上形成的AuxPdy合金的晶粒较小且数量较多,催化剂的酸量和活性组分的分散度较大,并且其上进行的加氢脱硫反应的活化能较低,这些因素均有利于催化剂活性的提高.更多还原

【Abstract】 TiO₂-Al₂O₃ composite oxides were prepared by the sol-gel method and calcined at 773-（1?073） K.The influence of calcination temperature of the composite oxide on the catalytic performance of Au-Pd/TiO₂-Al₂O₃ catalyst for the hydrodesulfurization of thiophene was studied.The prepared samples were characterized by X-ray diffraction,temperature-programmed desorption of adsorbed pyridine,temperature-programmed reduction,infrared spectroscopy,and nitrogen adsorption.The results showed that all the TiO₂-Al₂O₃ samples were mesoporous materials,and the TiO₂-Al₂O₃ calcined at 773 K had larger BET surface area and pore volume,and more Brnsted acid centers.Au-Pd/TiO₂-Al₂O₃ catalysts showed good activity for the hydrodesulfurization of thiophene.The Au-Pd supported on the TiO₂-Al₂O₃ calcined at 773 K showed the highest activity because of the stronger metal-support interaction,the more Au_xPd_y active centers formed on the catalyst surface and Brnsted acid sites,the higher metal dispersion,and the lower apparent activation energy.更多还原