Influence of Calcination Temperature on Performance of Monolith Catalyst MnO<SUB>2</SUB>-CeO<SUB>2</SUB>/Zr<SUB>0.25</SUB>Ti<SUB>0.25</SUB>Al<SUB>0.5</SUB>O<SUB>1.75</SUB> for Selective Catalytic Reduction of NO by NH<SUB>3</SUB> at Low Temperature

Abstract

The MnO2-CeO2/Zr0.25Ti0.25Al0.5O1.75 monolith catalyst was prepared by the incipient wetness method. The influence of calcination temperature on the textural and structural properties as well as the catalytic activity for selective catalytic reduction (SCR) of NO by NH3 was investigated by N2 adsorption-desorption at low temperature, oxygen storage capacity (OSC), X-ray diffraction, X-ray photoelectron spectroscopy, and NH3 temperature-programmed desorption. The results showed that the specific surface area, pore volume, and OSC of the catalyst decreased, while the average pore diameter increased with the increase of calcination temperature. The catalyst presented as amor- phous or crystallite when calcined in the temperature range of 500-700 o C. The catalyst calcined at 500 o C showed the largest surface acid amount and the strong interaction between the surface Mn and the support, which were beneficial to the SCR activity. The activity decreased with the increase of the calcination temperature. The activity was still considerable when the catalyst was calcined at 600 and 700 o C, but the activity obviously decreased at 800 o C.