Zeolite supported iron catalyst for nitric oxide reduction by ammonia in the presence of oxygen

Iron based H-ZSM-5 catalysts were used to study NO reduction with NH3 in the presence of oxygen with and without humid conditions. The iron based H-ZSM-5 was prepared by wet impregnation method and characterized by X-ray diffraction technique, BET surface area and SEM. TPD experiments showed low and high temperature NH3 desorption peaks. FTIR indicated only ammonia adsorbed species. Fe/ZSM-5 showed better NO, reduction with NH3 than H-ZSM-5. which was a poor catalyst for the NO, reduction. The catalytic activity did not show significant difference in the NOx conversion with and without water, but there was significant difference in NH3 conversion. It may be said that the dispersed Fe species and acid sites were the active centers for the reduction of NO with NH3 in the presence of oxygen.