Cu-SAPO-34 selective catalytic reduction (SCR) catalyst deactivates upon exposure to water vapor at temperatures lower than 100 °C, which deteriorates its application prospects. The deactivation under cycled aging-regeneration conditions can be categorized into two stages, namely reversible and irreversible deactivation. Based on SCR reaction tests, and characterizations with diffuse reflection infrared Fourier transform spectroscopy (DRIFTS), NH₃ temperature-programmed desorption (NH₃-TPD) and H₂ temperature-programmed reduction (H₂-TPR), it is concluded that the transformation of active isolated Cu(II) ions to Cu(OH)₂ is critical to both types of deactivation. Within the frame of reversible deactivation, Cu(OH)₂ can be converted back to SCR active Cu(II) ions by interacting with Brønsted acid sites during high-temperature regeneration. However, interactions between Cu(OH)₂ and hydrolyzed framework Al lead to the formation of CuAl₂O₄-like species, causing permanent loss of active Cu(II) ions and thus, irreversible deactivation.

Cu-SAPO-34选择性催化还原（SCR）催化剂在低于100°C的温度下暴露于水蒸气时会失活，从而降低了其应用前景。循环老化-再生条件下的失活可分为两个阶段，即可逆和不可逆失活。基于SCR反应测试，并通过漫反射红外傅里叶变换光谱（DRIFTS），NH _3程序升温脱附（NH ₃ -TPD）和H _2程序升温还原（H ₂ -TPR）表征，得出结论活性分离的Cu（II）离子向Cu（OH）_2的转化对于两种停用方式都至关重要。在可逆失活的框架内，通过在高温再生过程中与布朗斯台德酸位点相互作用，Cu（OH）₂可以转化为SCR活性Cu（II）离子。然而，Cu（OH）₂和水解的框架Al之间的相互作用导致形成类似CuAl ₂ O ₄的物质，导致活性Cu（II）离子的永久丢失，因此导致不可逆的失活。