Effect of vanadium surface density and structure in VOx/TiO2 on selective catalytic reduction by NH3

We investigated the correlation between vanadium surface density and VOx structure species in the selective catalytic reduction of NOx by NH3. The properties of the VOx/TiO2 catalysts were investigated using physicochemical measurements, including BET, XRD, Raman spectroscopy, FE-TEM, UV-visible DRS, NH3-TPD, H-2-TPR, O-2-On/Off. Catalysts were prepared using the wet impregnation method by supporting 1.0-3.0 wt% vanadium on TiO2 thermally treated at various calcination temperatures. Through the above analysis, we found that VOx surface density was 3.4 VOx/nm(2), and the optimal V loading amounts were 2.0-2.5 wt% and the specific surface area was 65-80m(2)/g. In addition, it was confirmed that the optimal VOx surface density and formation of vanadium structure species correlated with the reaction activity depending on the V loading amounts and the specific surface area size.