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催化剂采用等量浸渍法，先后将Ｃｏ与贵金属组分浸于γ－Ａｌ２Ｏ３上，经５００℃焙烧，４５０℃氢气还原制得（ｍＣｏ３Ｏ４／ｍＡｌ２Ｏ３＝０．０８，ｍ贵金属／ｍ催化剂＝１／１０００）．ＣＯ氧化活性的测定结果表明，贵金属Ｐｔ和Ｐｄ与Ｃｏ之间具有明显的协同催化作用，而Ｒｈ与Ｃｏ的协同作用较差．在Ｃｏ－Ｐｔ／γ－Ａｌ２Ｏ３和Ｃｏ－Ｐｄ／γ－Ａｌ２Ｏ３上，ＣＯ１００％转化的温度较在Ｃｏ／γ－Ａｌ２Ｏ３上下降了约６０℃，而在Ｃｏ－Ｒｈ／γ－Ａｌ２Ｏ３上仅下降了２５℃左右．ＸＲＤ和ＸＰＳ的表征结果表明，Ｃｏ／γ－Ａｌ２Ｏ３中Ｃｏ以高分散的金属Ｃｏ相和类似ＣｏＡｌ２Ｏ４的尖晶石相存在，而Ｃｏ－Ｍ／γ－Ａｌ２Ｏ３（Ｍ＝Ｐｔ，Ｐｄ，Ｒｈ）催化剂中，Ｃｏ相已完全被还原为零价．高分散的金属钴相和贵金属相的协同作用，可能与氧从贵金属至Ｃｏ相上的溢流效应有关．
The catalyst is impregnated by the same amount of impregnation method, Co and precious metal components are successively immersed in γ-Al2O3, calcined at 500 ° C and hydrogen reduced at 450 ° C to prepare (mCo3O4 / mAl2O3 = 0.08, m precious metal / ). The results of CO oxidation showed that there was a remarkable synergistic catalysis between Pt and Pd, while the synergistic effect between Rh and Co was poor. On the Co-Pt / γ-Al 2 O 3 and Co-Pd / γ-Al 2 O 3, the CO 100% conversion temperature dropped by about 60 ° C compared to that on Co / γ-Al 2 O 3, 25 ℃ or so. The results of XRD and XPS indicated that Co was present in Co / γ-Al2O3 with highly dispersed Co and CoAl2O4 spinels, whereas Co-M / γ-Al2O3 (M = Pt, Pd, Rh) Co phase has been completely reduced to zero. The synergistic effect of highly dispersed metallic cobalt phase and precious metal phase may be related to the overflowing effect of oxygen from precious metal to Co phase.