Morphological impact of V2O5/Al2O3 catalyst on the deactivation by SO2 for the reduction of NO with NH3

Abstract

The morphology of Al2O3 has been modified for use in the commercial SCR process as a support of V2O5/Al2O3 catalyst. A test program for accelerated deactivation at 400 degrees C and continuous deactivation at 250 degrees C has been developed for four kinds of V2O5/Al2O3 catalysts containing the distinctive pore size distributions of Al2O3. The program reveals that both the pore size and the surface area of the catalyst are important for the deactivation of V2O5/Al2O3 catalyst by SO2 to remove NO by NH3. This suggests that a high surface area catalyst with a large mean pore may be an ideal catalyst tolerable to catalyst deactivation by SO2 for SCR reaction. The deactivating agents formed on the catalyst surface confirmed by TGA, XPS and BET analysis of the deactivated catalysts may be Al-2(SO4)(3) and NH4Al(SO4)(2) at 400 degrees C, and NH4Al(SO4)(2), NH4HSO4 and (NH4)(2)SO4 at 250 degrees C.