A relationship between the V/V ratio and the surface dispersion, surface acidity, and redox performance of VO-WO/TiO SCR catalysts.

A series of VO-WO/TiO catalysts with different vanadium loading amounts were prepared by an impregnation method and were characterized by XRD, Raman spectroscopy, XPS, DRIFTS, Py-DRIFTS, NH-TPD, H-TPR, The results show that the catalytic activity is related to the ratio of V/V. The variation of the V/V ratio caused by the different dispersion states of vanadia oxide leads to changes in the surface acidity and redox properties of the catalysts. As the V/V ratio reaches the maximum value, the apparent activation energy ( ) required to form the transition state on the Brønsted acid sites is the lowest. Artificial regulation of vanadium loading to properly increase V/V content may affect the interactions between V, W, O and Ti atoms, which enhances NH-SCR reaction performance.