Mesoporous MnOx–CeO(2) composites for NH(3)-SCR: the effect of preparation methods and a third dopant

In this study, different preparation methods including an oxalate route, a nano-casting strategy and a traditional co-precipitation route were applied to obtain MnOx–CeO(2) mixed oxides for selective catalytic reduction (SCR) of NO with NH(3). The catalyst prepared from the oxalate route showed improved performance for NOx conversion and SO(2) + H(2)O durability. To further improve the SO(2) and H(2)O resistance of catalysts, ternary oxides were prepared from the oxalate route. The catalysts were studied by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, X-ray photoelectron spectroscopy (XPS), H(2) temperature-programmed reduction (H(2)-TPR), NH(3) temperature-programmed desorption (NH(3)-TPD), SO(2) temperature-programmed desorption (SO(2)-TPD), and in situ diffuse reflectance infrared fourier transform spectroscopy (in situ DRIFTS). The nickel–manganese–cerium ternary oxide showed the best SO(2) and H(2)O durability. The reason can be ascribed to its smaller pores, amorphous structure, and moderate amount of surface Mn(3+)/oxygen species, which could decrease chemical adsorption of SO(2).