摘要
采用溶胶凝胶(sol-ge1)、共沉淀(CP)和沉积沉淀(DP)法制备了介孔TiO2-Al2O3复合载体(简称复合载体);以噻吩加氢脱硫(HDS)为探针反应,考察了复合载体制备条件对负载型Au-Pd催化剂噻吩HDS反应性能的影响;并采用X射线衍射进行表征。结果表明,不同温度焙烧的TiO2一Al2O3复合载体都具有介孔结构,其中773 K焙烧制得的TiO2一Al2O3复合载体的比表面积和孔容较大,B酸中心较多;以乙醇还原的Au-Pd/TiO2-Al2O3催化剂的加氢脱硫活性较好。乙醇还原的Au-Pd/TiO2-Al2O3催化剂中Au-Pd之间及活性组分与载体之间的相互作用较强,形成AuxPdy合金的晶粒较小,活性组分的分散度和活性表面积较大,反应活化能较低,这些均有利于催化剂活性的提高。
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.h is found 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 Bronsted acid centers. The Au- Pd in the Au - Pd/TiO2 - Al2 O3 catalyst reduced by CH3 CH2OH has stronger interaction with support, larger active surface area and dispersion, small AuxPdy alloy grain and the apparent activation energy is lower, all these are advantageous to the catalyst active enhancement.
出处
《当代化工》
CAS
2007年第5期530-534,共5页
Contemporary Chemical Industry
