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采用等量浸渍法制备了一系列Ｃｒ－Ｍ／ＺｒＯ２双金属及单金属氧化物催化剂。ＣＯ氧化活性的测定结果表明，贵金属Ｐｄ和Ｐｔ与Ｃｒ之间具有明显的协同催化作用。在Ｃｒ－Ｐｄ／ＺｒＯ２和Ｃｒ－Ｐｔ／ＺｒＯ２上，ＣＯ１００％转化的温度较在Ｃｒ／ＺｒＯ２上分别下降了约２２０℃和１３０℃。ＸＲＤ和ＴＰＲ结果表明，Ｃｒ／ＺｒＯ２中Ｃｒ以表相和体相的Ｃｒ２Ｏ３存在，体相的Ｃｒ２Ｏ３与载体ＺｒＯ２间发生了强相互作用，从而抑制了ＺｒＯ２晶粒间的烧结和ｔ－ＺｒＯ２→ｍ－ＺｒＯ２的相变，微量Ｐｔ或Ｐｄ的加入使催化剂的还原性能发生明显变化，催化剂的还原性增强。对微量Ｐｔ和Ｐｄ在Ｃｒ／ＺｒＯ２中的作用做了一些探讨
A series of Cr-M / ZrO2 bimetallic and monometallic oxide catalysts were prepared by the same impregnation method. The results of the measurement of CO oxidation activity show that there is a remarkable synergistic catalysis between the noble metals Pd and Pt. On Cr-Pd / ZrO2 and Cr-Pt / ZrO2, the CO 100% conversion temperature was reduced by about 220 ° C and 130 ° C, respectively, over Cr / ZrO2. The results of XRD and TPR show that the Cr in Cr / ZrO2 exists in the form of Cr2O3 in the form of phase and bulk and the strong interaction between Cr2O3 in the bulk and ZrO2 in the bulk and the sintering of ZrO2 grains and the reduction of t-ZrO2 → m -ZrO2 phase transformation, the addition of trace Pt or Pd significantly changes the reduction performance of the catalyst, reducing the catalyst enhanced. The effect of trace Pt and Pd in Cr / ZrO2 is discussed