Low-temperature SCR of NOx with NH3 over carbon-ceramic supported catalysts

A new method for preparing vanadium oxide supported on carbon-ceramic cellular monoliths is described. This includes a support oxidation step with HNO3, followed by ionic exchange with a NaOH solution, equilibrium adsorption impregnation of VO2+ and thermal treatment. As a result an active catalyst for low-temperature selective catalytic reduction (SCR) reaction is obtained. The V-catalyst is more resistant to SO2 poisoning than the previously developed Mn-catalyst. Inhibition by water is reversible for both types of catalysts. Testing of the vanadium catalyst after subjecting it to the outlet gas stream of a power plant shows fast deactivation until constant residual activity is reached. Deactivation seems to be caused by arsenic poisoning and the formation of superficial sulphates.