Effect of Bimetal Element Doping on the Low-Temperature Activity of Manganese-Based Catalysts for NH(3)-SCR

A series of novel Mn(6)Zr(1-x)Co(x) denitrification catalysts were prepared by the co-precipitation method. The effect of co-modification of MnO(x) catalyst by zirconium and cobalt on the performance of NH(3)-SCR was studied by doping transition metal cobalt into the Mn(6)Zr(1) catalyst. The ternary oxide catalyst Mn(6)Zr(0.3)Co(0.7) can reach about 90% of NO(x) conversion in a reaction temperature range of 100–275°C, and the best NO(x) conversion can reach up to 99%. In addition, the sulfur resistance and water resistance of the Mn(6)Zr(0.3)Co(0.7) catalyst were also tested. When the concentration of SO(2) is 200ppm, the NO(x) conversion of catalyst Mn(6)Zr(0.3)Co(0.7) is still above 90%. 5 Vol% H(2)O has little effect on catalyst NO(x) conversion. The results showed that the Mn(6)Zr(0.3)Co(0.7) catalyst has excellent resistance to sulfur and water. Meanwhile, the catalyst was systematically characterized. The results showed that the addition of zirconium and cobalt changes the surface morphology of the catalyst. The specific surface area, pore size, and volume of the catalyst were increased, and the reduction temperature of the catalyst was decreased. In conclusion, the doping of zirconium and cobalt successfully improves the NH(3)-SCR activity of the catalyst.