Deactivation of Ce-Ti Oxide Catalyst by K3PO4 for the Selective Catalytic Reduction of NO with NH3

The effect of K3PO4 on the selective catalytic reduction of NO with NH3 over a Ce-Ti oxide catalyst was investigated using XRD, BET, XPS, NH3-TPD, H2-TPR and activity measurements. The results showed that K3PO4 deactivated the Ce-Ti oxide catalyst seriously. The drop in the amount of Ce3+ was accompanied by a decrease in oxygen vacancies and active surface oxygen species, which was disadvantageous to the SCR reaction over the Ce-Ti oxide catalyst. In addition, a reduction in the Brønsted surface acidity and reducibility was also responsible for the deactivation of the Ce-Ti oxide catalyst by K3PO4.