Catalytic performance and hydrothermal stability of Cu/SAPO-34 catalyst in the selective catalytic oxidation of NH₃

A series of Cu/SAPO-34 catalysts for ammonia selective catalytic oxidation (NH₃-SCO) were prepared by impregnation method. The results of activity test indicated that the NH₃ conversion over 10%-Cu/SAPO-34 catalyst was nearly 100% at 300℃ and N₂ selectivity was more than 90% in the range of test temperature. Meanwhile, the characterization results of XRD, BET, UV-vis, H₂-TPR and XPS showed that the highly dispersed CuO species in Cu/SAPO-34 catalyst were the main active component. Furthermore, the aged 10%-Cu/SAPO-34 catalyst performed better NH₃-SCO activity at low temperature, while the N₂ selectivity dramatically decreased at 325℃, SAPO-34 zeolite crystallinity would deteriorate under hydrothermal treatment.