Cu/ZSM-5 is able to catalyze the reduction of NO_x to N₂ (NH₃-SCR), but the poisoning effect of K in this regard has been barely studied. Herein, the poisoning effect of K with respect to Cu/ZSM-5 in NH₃-SCR was established via catalytic testing, and both Cu/ZSM-5 and K-poisoned Cu/ZSM-5 were probed by using XRD, N₂ sorption, TEM, H₂-TPR, XPS, NH₃-TPD, and NO-TPD. In addition to these characterization tools, in-situ DRIFTS was employed to probe the adsorbed species and reaction intermediates, thus giving important information about the possible reaction mechanisms. In all, the presence of K led to decreased exposure of active CuO dispersed on ZSM-5, inhibited the adsorption of NH₃ and NO_x to some extent, minimized the formation of active bridged nitrate, and facilitated the formation of inactive bidentate nitrate.

Cu/ZSM-5 能够催化 NO _x还原为 N ₂ (NH ₃ -SCR)，但 K 在这方面的中毒效应几乎没有研究。在此，K对NH ₃ -SCR中Cu/ZSM-5的毒化作用是通过催化测试建立的，并通过XRD、N ₂探测Cu/ZSM-5和K中毒的Cu/ZSM-5吸附、TEM、H ₂ -TPR、XPS、NH ₃ -TPD 和 NO-TPD。除了这些表征工具，原位DRIFTS 被用来探测吸附的物质和反应中间体，从而提供关于可能的反应机制的重要信息。总之，K的存在导致分散在ZSM-5上的活性CuO的暴露减少，在一定程度上抑制了NH ₃和NO _x的吸附，最大限度地减少了活性桥接硝酸盐的形成，并促进了非活性二齿硝酸盐的形成。