Deeply revealing the mechanism of the synergistic effect of Cu and P on alleviating CaO poisoning performance of V-W-Ti catalysts in cement kilns

CaO was the inevitable cause of V 2 O 5 -WO 3 -TiO 2 catalyst (VWTi) poisoning in cement kilns. The significant reduction in NO conversion was due to the combination of CaO and active species of the vanadium -based catalyst. In this work, the VWTi catalysts were modified with different contents of Cu and P to improve resistance to CaO, thereby extending the service life of catalysts in cement kilns. By doping Cu and P, the CaVWCu 3 P 5 Ti had better catalytic activity, reduced the poisoning effect of CaO to V 5+ , thus protecting the redox properties and increasing the surface acidic sites of the catalyst. Meanwhile, the in-situ DRIFTs results showed that the poisoning effect of CaO was weaker on the Ca-VWCu 3 P 5 Ti than that of the Ca-VWTi. In addition, the NH 3 and NO species could be effectively adsorbed and activated on the surface of the Ca-VWCu 3 P 5 Ti by E -R mechanism. In this way, the harm of CaO to the vanadium -based catalysts was effectively reduced. This work provided a promising strategy to design vanadium -based catalysts with superior resistance to CaO in NH 3 -SCR reaction.