Promotional Effect on Selective Catalytic Reduction of NOx with NH3 over Overloaded W and Ce on V2O5TiO2 Catalysts

Abstract EN

W and Ce are known to be a good promoters to improve selective catalytic reduction (SCR) activity for V2O5/TiO2 catalysts.

This work aimed at finding the optimum ratio and loading of promoters (W and Ce) on V2O5/TiO2 catalyst in order to improve SCR reactivity in low temperature region and to minimize N2O formation in high temperature region.

In addition, we changed the order of impregnation between W and Ce precursors on V2O5/TiO2 catalyst during the preparation and observed its effect on SCR activity and N2 selectivity.

We utilized various analytical techniques, such as N2 adsorption-desorption, X-ray diffraction (XRD), and temperature-programmed reduction with hydrogen (H2 TPR) to investigate the physicochemical properties of catalysts.

It was found that W- and Ce-overloaded V2O5/TiO2 catalyst such as W/Ce/V/TiO2 (15 : 15 : 1 wt%) showed the most remarkable DeNOx properties over the wide temperature region.

Additionally, this catalyst significantly suppressed N2O formation during SCR reaction, especially in high temperature region (350–400°C).

Based on the characterization results, it was found that such superior activity originated from the improved reducibility and morphology of W and Ce species on V2O5/TiO2 catalyst when they are incorporated together at high loading.