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以ＣＯ氧化为模型反应，考察了Ｐｄ／γ－ Ａｌ２Ｏ３ 体系中以不同方式加入ＭｇＯ 对催化剂性能的影响，结果证实助剂ＭｇＯ能较大幅度提高Ｐｄ／γ－ Ａｌ２Ｏ３ 对ＣＯ 氧化反应的催化活性。ＭｇＯ能均匀地分散于γ－ Ａｌ２Ｏ３ 上，使ＣＯ的起燃温度降低达４４℃。对样品的ＸＲＤ、ＴＰＲ、ＸＰＳ及氧吸附等表征结果表明，共浸型的Ｐｄ－ ＭｇＯ／Ａｌ２Ｏ３ 体系具有最高的Ｐｄ 分散度；分浸型的Ｐｄ－ ＭｇＯ／Ａｌ２Ｏ３ 体系Ｐｄ 分散度亦高于Ｐｄ／Ａｌ２Ｏ３ ，且能提高催化剂表面活性Ｐｄ 的含量。表面ＭｇＯ对氧的浓缩作用有利于ＣＯ 的氧化。并讨论了助剂ＭｇＯ与Ｐｄ 的协同作用对其活性的影响
The effect of adding MgO on the catalyst performance in Pd / γ-Al2O3 system was investigated by CO oxidation. The results showed that the promoter MgO can significantly improve the catalytic activity of Pd / γ-Al2O3 for CO oxidation. MgO can be uniformly dispersed on γ-Al2O3, so that the CO light-off temperature decreased by 44 ℃. The results of XRD, TPR, XPS and oxygen adsorption showed that the co-impregnated Pd-MgO / Al2O3 system had the highest Pd dispersion. The Pd dispersion of Pd-MgO / Al2O3 system was also higher than that of Pd / Al2O3, and can improve the catalyst surface active Pd content. Surface MgO concentration of oxygen is conducive to the oxidation of CO. The effects of the additive MgO and Pd on their activity were discussed