NO_x Reduction with Resistance Against Multiple Poisoning Agents over Inherent SO₄^2- Modified V₂O₅/CeO₂ Catalysts

It's a big challenge to use commercial catalysts in the non-electric industries because complex flue gas containing alkali metals, heavy metals and SO2 could deactivate catalysts. In this study, we demonstrate that inherent SO42- modified V2O5/CeO2 catalysts exhibit remarkable resistance to multi-poisons including K, Pb and SO2. The mechanisms of multiple poisoning resistance are revealed, and the evolutions of interactions between various poisons and different catalysts are elucidated. It is evidenced that K or Pb could bond on the inherent SO42- sites of catalysts; the interaction of K with Pb could impair the poisoning effects of K & Pb on catalysts; the newly formed surface SO42- species with the introduction of SO2 could bond with K dominantly, decrease the interaction between K and Pb, and relieve the effects of Pb on catalysts. K & Pb & SO2 co-poisoned catalysts still maintain high adsorption of NH3/NH4+ and NOx species and a superior NOx reduction efficiency via the Langmuir-Hinshelwood reaction pathway, leading to the ultra-strong resistance of multi-poisons. This work successfully achieves efficient and stable NOx removal in the presence of K & Pb & SO2, and sheds light on the interactions between various poisons and different catalysts, which is significant to abate NOx emissions for non-electric industries.