Catalytic reduction of N2O by C2H4 over Fe-ZSM-5: formation and nature of carbonaceous deposits and influence of the addition of O2

The catalytic reduction of dinitrogen monoxide (N2O) by ethylene (C2H4) in the absence and presence of O2 is studied over Fe-ZSM-5 catalysts. Two types of carbonaceous deposits (Cα, Cβ) are formed on Fe-ZSM-5 during the reduction of N2O by C2H4 in the absence of O2. The catalytic activity of Fe-ZSM-5 decreases with an increase in the amount of Cα, while the catalytic activity is not affected by the presence of Cβ. The formation of these carbonaceous deposits is suppressed by the presence of O2 in the feed gas, and the catalytic reduction of N2O by C2H4 is promoted by O2, since deactivation of Fe sites is prevented in the presence of O2.