Selective catalytic reduction of nitric oxide with ammonia in presence of oxygen over Mn-ZSM5

Abstract

Selective catalytic reduction of NO with NH3 in presence of oxygen with and without humid conditions has been studied over Mn-ZSM5 and H-ZSM5. The Mn-ZSM5 has been prepared by wet impregnation method, characterized by X-ray diffraction technique, atomic absorption spectroscopy and BET surface area. Mn-ZSM5 shows better NOx reduction than H-ZSM5. H-ZSM5 alone is a poor catalyst for NOx reduction with NH3, but metal incorporated catalyst becomes active. In the presence of humid condition Mn-ZSM5 gives lower NOx and NH3 conversions. It may be concluded that the dispersed manganese species are the active centres for the selective catalytic reduction of NO with NH3 in the presence of oxygen.