1P-526 : MnO x -CeO 2 -WO 3 /TiO 2 catalysts with different W/Ce ratio for low-temperature NH 3 -SCR: Surface characteristics and dispersion states in relation to Activity of NOx reduction

MnOx-CeO2-WO3/TiO2 catalysts with different W/Ce ratio were synthesized by the sol-gel method for selective catalytic reduction (SCR) of NOx by NH3 reductant at low-temperatures. The X-ray diffraction (XRD) patterns show that all samples were anatase TiO2 phase, indicating that MnOx, CeO2, and WO3 were well-dispersed on TiO2 support in amorphous state. The surface acidity of MnOx-CeO2-WO3/TiO2 catalysts were increased with increasing of W/Ce ratio from 0/10 to 9/1, thus the catalytic activity of W/Ce = 9/1 catalyst was much higher than others in the temperature range of 100 - 300°C under a gas hourly space velocity (GHSV) = 10,000 h-1.