柴油车排放的NOx会对人体和环境造成严重危害，氨选择性催化还原技术能有效减少NOx排放。Cu-SAPO-34催化剂具有优异的NOx转化活性、高温水热稳定性和低廉的价格，有望应用于国VI柴油车尾气后处理系统，但是低温水热稳定性问题成为制约该催化剂应用的瓶颈。本项目首先研究老化工况（存储、启动、停止）和再生过程（热处理）对Cu-SAPO-34催化剂影响，通过表征催化剂活性中心和载体的变化过程，推导催化剂的低温水热失活和再生机理，为催化剂设计提供理论指导；然后研究表面吸附物（固相或气相吸附物）对催化剂活性中心、载体和低温水热稳定性的影响；接着研究催化剂内部组成（阳离子含量和位置，硅含量、硅环境和硅分布）和低温水热稳定性间的关系。最后根据上述研究结论，通过调变制备过程，得到低温水热稳定性优异的Cu-SAPO-34催化剂，为研制符合市场需求的脱硝催化剂提供理论依据和技术储备。

The NOx emitted from diesel engine would cause serious health and environmental issues, and the selective catalytic reduction of NOx by NH3 is one of the most efficient technologies to eliminate the NOx emission. Due to the excellent NOx conversion performance, prominent high-temperature hydrothermal stability, and low cost, the Cu-SAPO-34 catalyst is regarded as the promising catalyst, which could be applied in diesel after-treatment system to meet the China VI standard. However, Cu-SAPO-34 catalyst is sensitive to the low-temperature vapor, which limits its practical application.. Understanding the deactivation and regeneration process is essential for synthesizing hydration stable Cu-SAPO-34 catalysts. Thus, the effect of aging condition (simulate storage, cold-start and turn-off period) and regeneration process on the Cu-SAPO-34 catalysts will be explored firstly, the deactivation and regeneration mechanism will be deduced by the progressive changing process of the active sites and carrier properties, which will be characterized by multiple apparatuses. Then, the effect of surface adsorption-species on the active sites, carrier properties and low-temperature stability of Cu-SAPO-34 catalyst will be studied, respectively, the conclusion from the results will be a guide for the preparation of the catalyst. After that, the relationship between the inner-properties of catalyst (the content and the location of the cation, Si content, Si environment and Si distribution) and the low-temperature stability of Cu-SAPO-34 catalyst will be established. Finally, the Cu-SAPO-34 catalyst with prominent low-temperature stability will be obtained by adjusting the preparation process according to the above conclusions. The implement of this project will provide theoretical basis and technical reserves for the development of denitration catalyst to meet market demand.