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研究了双阳离子共交换Ｃｕ，Ｗｅ－ＺＳＭ－５分子筛里第二种金属离子对ＮＯ催化分解的影响，并用ＸＲＤ、ＥＸＡＦＳ、和Ｏ＿２－ＴＰＤ－ＭＳ多种手段对催化剂加以表征．分子筛中铜化学环境因为共交换阳离子的存在发生了明显变化，并对应分子筛氧脱附性能的变化．这种变化因不同的阳离子而异：Ｍｇ￣２＋，Ｃｏ￣２＋等增强铜催化分解ＮＯ活性的共存阳离子使铜氧配位数增加，配位距离变大，从而便氧的脱附能力大幅度增强；而Ｋ￣＋等降低活性的阳离子的效应相反．该效应的强度与ＮＯ分解活性的变化较好地一致．这说明分子筛催化剂的改性可以通过共交换阳离子来实现．
The effect of the second metal ions on the catalytic decomposition of NO in Cu-We-ZSM-5 molecular sieves was investigated. The catalysts were characterized by XRD, EXAFS and O_2-TPD-MS. The chemical environment of copper in zeolites changed obviously due to the presence of coexchange cations and corresponded to the change of oxygen desorption performance of molecular sieves. This change due to different cations: Mg ~ 2 +, Co ~ 2 + and other enhance copper catalytic decomposition of NO activity of coexisting cations so that copper and oxygen coordination number increases, the coordination distance becomes larger, so that oxygen desorption capacity significantly Enhanced; and K ~ + to reduce the activity of the opposite effect of the cation. The intensity of this effect is in good agreement with changes in NO breakdown activity. This shows that the molecular sieve catalyst modification can be achieved by co-exchange of cations.