Cu-based SAPO-18, SAPO-18/34 intergrowth and SAPO-34 zeolites were applied for the selective catalytic reduction of NO_x by ammonia (NH₃-SCR) catalysts. Comprehensive characterization results revealed that the SAPO-18/34 with higher amount and strength of acid sites could facilitate the generation of more isolated copper ions (Cu²⁺ and Cu⁺) and suppress the formation of CuO_x, which might account for the fact that intergrowth crystal structure of Cu-SAPO-18/34 exhibited higher fresh NH₃-SCR activity, more robust hydrothermal durability and better SO₂-resistance ability than that Cu-SAPO-18 and Cu-SAPO-34. In situ DRIFTS results provided the formation of reaction intermediates, such as -NH₂, NH₄⁺, NO₃^-, NO₂^-, etc. Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) reaction mechanisms were both involved in Cu-based SAPO-18 and SAPO-18/34 intergrowth zeolites, but the L-H mechanism dominated the NH₃-SCR reaction, in addition, Cu-SAPO-34 only followed “L-H” mechanism.

的Cu-SAPO-18，SAPO-18/34和共生SAPO-34沸石被应用于选择性催化还原NO的_X由氨（NH ₃ -SCR）催化剂。综合表征结果表明，具有较高酸性位点数量和强度的SAPO-18 / 34可以促进更多离析的铜离子（Cu ²⁺和Cu ⁺）的生成并抑制CuO _x的形成，这可能是造成这一事实的原因。 Cu-SAPO-18 / 34的共生晶体结构表现出更高的新鲜NH ₃ -SCR活性，更强的水热耐久性和更好的SO ₂抗性比Cu-SAPO-18和Cu-SAPO-34高。原位DRIFTS结果提供反应中间体的形成，如-NH ₂，NH ₄ ⁺，NO ₃ ^-，NO ₂ ^- ，等等ELEY-Rideal（ER）和Langmuir-欣谢尔伍德（LH）的反应机制均被卷入铜基SAPO-18和SAPO-18 / 34共生沸石，但LH机理主导了NH ₃ -SCR反应，此外，Cu-SAPO-34仅遵循“ LH”机理。