One-step Synthesis, Characterization and Ammonia-selective Catalytic Reduction Performance of Cu-SAPO-34 Catalyst

Abstract

The Cu-SAPO-34 catalyst, a promising selective catalytic reduction (SCR) catalyst for the denitration of mobile sources, has attracted widespread research interest due to its wide temperature window, remarkable catalytic performance and good stability. In this study, a series of Cu-SAPO-34 catalysts with varying Cu contents were synthesized by the one-step hydrothermal method. The physicochemical properties of the catalysts were investigated by characterizations, and the reasons for the well-activity catalysts were analyzed. The acidic sites on the SAPO-34 zeolite can adsorb and activate NH₃, while the copper active sites can promote the activation and reduction of NO_x, accelerating the reaction process of SCR. In this study, Cu-SAPO-34 with Cu content of n(Cu)/n(C₉H₂₁AlO₃)=0.075 has good framework stability, which produced more free Cu²⁺ ions and the Cu species are evenly distributed on the carrier surface, and the appropriate amount of acid sites. Therefore, the Cu_0.075-SAPO-34 catalyst exhibits the highest NO conversion performance, maintaining a NO conversion rate above 90 % within the temperature range of 165–450 °C.