Insight into the effects of C3H6 on fresh and hydrothermally aged Cu-SSZ-39 catalysts

Hydrocarbons (HCs), as major poisoning substances, have a crucial influence on NH3-SCR catalysts. In this work, the effects of C 3 H 6 on fresh and hydrothermally aged Cu-SSZ-39 catalysts with different copper contents were investigated. All catalysts suffered a deactivation above 250 degrees C, especially between 30 0-40 0 degrees C, which was mainly related to the reaction between NH3 and C 3 H 6 . However, the hydrothermally aged and the high-copper-loaded Cu-SSZ-39 catalysts could achieve a recovery of NH3-SCR performance at high temperatures. Such activity recovery was attributed to the oxidation of C 3 H 6 by CuxOy species, which therefore inhibited the reaction between NH3 and C 3 H 6 . As a result, more NH3 could be available for the NH3-SCR reaction and the Cu-SSZ-39 catalysts could maintain a good catalytic activity. Based on these findings, we proposed that high loaded Cu-SSZ-39 catalysts with a little CuOx formed are preferred for application. (c) 2025 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.