Hydrothermal tolerance towards different temperature conditions over two typical Cu/CHA catalysts

Abstract This research focused on the hydrothermal tolerance of Cu/SAPO-34 and Cu/SSZ-13 catalysts. Either low- or high-temperature aging decreases the catalytic property of Cu/SAPO-34. Cu/SAPO-34 lost some isolated copper sites, and new copper-aluminum complexes CuAl2O4 and Al-rich CuOx clusters formed after low temperature aging. High temperature aging resulted in CuOx clusters and AlPO4 species formed, which led to the loss of Cu2+ active sites and surface nitrates adsorbed sites over Cu/SAPO-34. Cu/SSZ-13 retained the catalytic performance after low temperature aging but was totally intolerant to high temperature aging. High temperature hydrothermal aging led to the loss of active sites, lack of surface nitrates adsorbed sites, and serious structural degradation over Cu/SSZ-13.