Study of Preparation and Activity of Selective Catalytic Reduction Nano-loading Catalysts

Nano-TiO2/ceramic supported V2O5-WO3 catalyst (V2O5-WO3/TiO2(C)) was prepared by sol-gel method and impregnation method. The V2O5-WO3/TiO2(C) catalyst was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was studied the influences of heat treatment temperature of TiO2 gel and WO3 loadings on reaction temperature windowand catalyst resistance to SO2 poisoning in NH3-SCR system. The effects of NH3/NO ratio, O2 concentration and gas hourly space velocity (GHSV) on the activity of the catalysts were also evaluated. The results show that V2O5-WO3/TiO2(C) catalyst has high and steady activity over the temperature range 260~420℃. The V2O5-WO3/TiO2(C) (anatase) catalyst shows high resistance to SO2 poisoning. To the contrary, The V2O5-WO3/TiO2(C) (mixture of anatase and rutile) catalyst is easily poisoned by SO2. SO2 poisoning is reversible and regeneration is feasible. The results also show that increasing of WO3 loadings can improve the activity of the catalyst.