Effect of treatment atmosphere on the vanadium species of V/TiO2 catalysts for the selective catalytic reduction of NOx with NH3

Different treatment atmospheres, including oxidizing, inert and reducing conditions, all affected vanadium species and deactivated the V/TiO2 catalyst to some extent in NH3-SCR. The amount of active polymeric vanadyl species decreased in the following sequence: V/Ti > V/Ti–O2 > V/Ti–N2 > V/Ti–NH3.