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双交换Ｃｕ，ｐｄ－ＺＳＭ－５催化剂（Ｃｕ交换度为１０５％，Ｐｄ交换度分别为３．４％和３３％）对ＣＯ氧化反应有活性增强作用，对ＮＯ分解反应不存在增强效应．双交换催化剂在于交换程序不同，而表面物种不同，活性组分的分布状态不同，因而有不同的活性．先交换Ｃｕ，４００℃焙烧后再交换ｐｄ的Ｃｕ－Ｐｄ－ＺＳＭ－５催化剂，对上述两类反应的活性存双组分催化剂中均为最高．Ｈ_２－ＴＰＲ谱表明，共交换的Ｃｕ－Ｐｄ－ＺＳＭ－５中尚有部分ＣｕＣｌ＋占据了部分交换位置，而使ＣＯ氧化活性稍有下降．Ｎ_２－ＤＴＡ和Ｈ_２－ＴＰＲ谱结果表明，Ｐｄ交换到Ｃｕ－ＺＳＭ－５中后，抑制了吸附水和水合铜化合物的形成，由此提高了在２００—３００℃时氧的吸附量．后者的大小和ＣＯ氧化活性有顺变关系．Ｎ_２－ＤＴＡ谱中３４０—４４５℃的放热峰可能分别表征了和ＮＯ分解活性有关的铜氧桥或把氧桥的形成，该放热峰的峰温愈低，峰面积愈大，则ＮＯ分解活性愈高．
The double exchange of Cu, Pd-ZSM-5 catalyst (Cu exchange degree of 105%, Pd exchange degree of 3.4% and 33% respectively) enhanced the activity of CO oxidation without any enhancement effect on NO decomposition reaction. Double exchange catalyst is different in the exchange program, and the surface species, the distribution of active components of different states, which have different activities. The Cu-Pd-ZSM-5 catalyst which was first exchanged for Cu and then exchanged for Pd after calcination at 400 ° C was the highest among the active two-component catalysts for the above two types of reactions. H_2-TPR spectra showed that some CuCl + in the coprecipitated Cu-Pd-ZSM-5 occupied part of the exchange sites, leaving a slight decrease in CO oxidation activity. The results of N 2 -DTA and H 2 -TPR showed that the exchange of Pd into Cu-ZSM-5 inhibited the formation of adsorbed water and hydrated copper compounds, which increased the oxygen adsorption at 200-300 ℃. The latter size and CO oxidation activity has a cataract relationship. The exothermic peak at 340-445 ℃ in N 2 -DTA spectrum may represent the formation of copper bridge or oxygen bridge related to NO decomposition activity, respectively. The lower the peak temperature of the exothermic peak, the larger the peak area. NO Decomposition activity higher.