Enhanced activity of an In–Fe2O3/H-ZSM-5 catalyst for NO reduction with methane

Selective reduction of NO by CH4 on an In–Fe2O3/H-ZSM-5 catalyst was investigated in the presence of excess oxygen. Compared with In/H-ZSM-5, the In–Fe2O3/H-ZSM-5 catalyst with high Fe2O3 contents showed higher activity in a wide range of reaction temperatures. It was found that the addition of Fe2O3 yielded a promotion effect on CH4 activation. The influence of water vapor on NO conversion was also investigated. The activity of the In/H-ZSM-5 catalyst has been found to be strongly inhibited by water vapor, while the In–Fe2O3/H-ZSM-5 catalyst remained fairly active in the presence of 3.3% steam.