Au/CeO_2、Pd/CeO_2和Au-Pd/CeO_2催化剂甲醇部分氧化制氢性能的研究

采用沉积沉淀法制备了Au/CeO2、Pd/CeO2和Au-Pd/CeO2催化剂,研究了催化剂的甲醇部分氧化制氢性能,并运用XRD、UV-Vis、TPR、H2-TPD和CO-TPD等手段对催化剂进行了表征。结果表明,与Pd/CeO2和Au/CeO2相比,Au-Pd/CeO2双金属催化剂显示出较高的催化活性和较高的氢产率,这是由于Au和Pd的相互作用减少了Pd对反应产物H2的吸附,有利于活性中心再生,且减小了H2的深度氧化,同时Au和Pd相互作用使金粒子较稳定、不易聚集,有利于高温时H2选择性的稳定。

Production of hydrogen by partial oxidation of methanol over Au/CeO2, Au-Pd/CeO2 and Pd/CeO2 catalysts

Au/CeO2, Au-Pd/CeO2 and Pd/CeO2 catalysts were prepared by deposition-precipitation (DP) method, and their activities and H2 selectivity for partial oxidation of methanol were evaluated. XRD, UV-Vis, TPR, H2-TPD and CO-TPD were used to char- acterize the catalysts. In comparison with Au/CeO2 and Pd/CeO2 catalysts, Au-Pd/CeO2 catalyst showed higher activity and hydrogen yield for partial oxidation of methanol reaction. It was due to weaker adsorption of hydrogen resulting from interaction between gold and palladium species, which was favorable to regeneration of active center and decreased further oxidation of hydrogen. Moreover synergetic interaction between gold and palladium species suppressed aggregate of Au particles, which was favorable to stabilization of H2 selectivity at high reaction temperature.