The Poisoning of V2O5-WO3/TiO2 and V2O5-Ce(SO4)2/TiO2 SCR Catalysts by KCl and The Partial Regeneration by SO2

Poisoning effects by alkali metal chlorides is one of the major reasons for the deactivation of SCR catalyst in biomass-fired plants. In this study, the influence of KCl on two vanadium-based catalysts with different promoters, V2O5-WO3/TiO2 and V2O5-Ce(SO4)2/TiO2, was investigated. The catalytic activity of the fresh V2O5-WO3/TiO2 was higher than that of V2O5-Ce(SO4)2/TiO2 at low temperatures. V2O5-Ce(SO4)2/TiO2 performed better than V2O5-WO3/TiO2 when KCl was deposited on the catalyst surface. Both poisoned catalysts were efficiently regenerated by SO2 treatment. The characterization results show that the reducibility and acidity of the catalysts were weakened by KCl deposition but regenerated by SO2.