Combination of Low- and Medium-Temperature Catalysts for the Selective Catalytic Reduction of NOxwith NH3

In this study, we developed a novel combination model for different types of catalysts, which could generate synergistic effects for the catalysts with different functions. A Mn(3)CeO(x)catalyst with good low-temperature activity and a Ce(0.1)TiO(x)catalyst with good medium and high temperature activities were selected to make the combination and show synergistic effects. The combination of Ce0.1TiOx-Mn3CeOx(with Ce(0.1)TiO(x)located at the upstream of Mn3CeOx) showed high NO(x)conversions in the whole temperature range, together with relatively low N2O formation, indicated the synergistic effects between the Ce(0.1)TiO(x)and Mn(3)CeO(x)catalysts. This combination model can be extended widely to various NH3-SCR catalysts and therefore has universal significance.