InsightintotheeffectsofC3H6onfreshandhydrothermallyagedCu-SSZ-39catalysts

Hydrocarbons （HCs）,as major poisoning substances,have a crucial influence on NH3-SCR catalysts.In this work,the effects of C3H6 on fresh and hydrothermally aged Cu-SSZ-39 catalysts with different copper contents were investigated.All catalysts suffered a deactivation above 250°C,especially between300-400℃,which was mainly related to the reaction between NH3 and C3H6.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 C3H6 by CuxOy species,which therefore inhibited the reaction between NH3 and C3H6.As a result,more NH3could 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 CuO xformed are preferred for application.