Catalysis Letters, Vol.151, No.4, 966-979, 2021
Low-Temperature Selective Catalytic Reduction of NO with NH3 Over Mn-Ti Oxide Catalyst: Effect of the Synthesis Conditions
A series of Mn-Ti oxide catalysts were synthesized by the sol-gel method and the effects of different synthesis conditions were investigated in sequence. The microstructures and properties of the catalysts were characterized by using N-2 adsorption-desorption, XRD, SEM, H-2-TPR, NH3-TPD, Raman and XPS. The catalytic performance over Mn-Ti oxide catalysts prepared under different synthesis conditions for the low-temperature SCR of NO with NH3 were also comparatively evaluated. The results reveal that the calcination temperature and metal source play a significant role in the characteristics and the SCR activities of the catalysts. A relatively low calcination temperature is beneficial to low-temperature SCR activity. Manganese nitrate or manganese acetate as the Mn source combining with tetrabutyl titanate as Ti source can achieve high SCR activities. The excellent low-temperature NH3-SCR activity can be ascribed to the appropriate textural properties, amorphous Mn-oxides with equal ratio of Mn3+/Mn4+, good low-temperature reducibility and abundant surface B-acid sites. [GRAPHICS] .