Improved catalytic activity and N-2 selectivity of Fe-Mn-O (x) catalyst for selective catalytic reduction of NO by NH3 at low temperature

FeO (x) , MnO (x) and Fe-Mn-O (x) catalysts were prepared by the co-precipitation method and used for the selective catalytic reduction (SCR) of NO (x) by NH3 at low temperature. Fe-Mn-O (x) catalyst showed the best catalytic activity and above 80% NO (x) conversion was obtained at 50-150 A degrees C. Nearly 80% N-2 selectivity of Fe-Mn-O (x) catalyst was acquired at the whole temperature range. The excellent low-temperature SCR activity and N-2 selectivity were ascribed to the abundant surface acid sites, the formation of Fe-O-Mn species, co-existence of multiple valence states (Mn4+, Mn3+ and Mn2+) and the proper redox ability. In addition, the interaction between Fe and Mn species over the Fe-Mn-O (x) catalyst was responsible for the improvement of SCR performance and N-2 selectivity. Fe-Mn-O (x) catalysts were prepared by the co-precipitation method and used for the selective catalytic reduction (SCR) of NO (x) by NH3 at low temperature. The formation of Fe-O-Mn species contributed to the co-existence of multiple valence states (Mn4+, Mn3+, Mn2+, Fe3+ and Fe2+), resulting in an increase in catalytic activity and N-2 selectivity. Besides, the abundance of acid sites was responsible for the superior N-2 selectivity. [GRAPHICS] .