Enhancing hydrothermal stability of NH3-SCR reaction over Cu-SSZ-52 catalyst by increasing Si/Al ratio

Cu-SSZ-52 zeolites, celebrated for their exceptional low-temperature NH3-SCR activity, are hampered by poor hydrothermal stability attributable to a low Si/Al ratio, which significantly constrains their practical utility. In this work, we successfully synthesized Cu-SSZ-52 catalysts with a Si/Al ratio as high as 7 for the first time. iDPCSTEM and PXRD analysis confirmed that the catalysts have the same structure as SSZ-52. Notably, the Cu-SSZ-527 catalyst showcased enhanced deNOx performance both prior to and following hydrothermal aging, outperforming Cu-SSZ-52 catalysts with a Si/Al ratio of 4 and Cu-SSZ-13 catalysts with a Si/Al ratio of 7. Our findings underscore that a continuous increase in the Si/Al ratio resulted in the promotion of deNOx activity and hydrothermal stability of Cu-SSZ-52 catalysts.