Electron Confinement Effect Induced by Ce-O-Fe Structure Boosting Catalyst So2 Resistance in Nh3-Scr Reaction

The problem of how to improve the SO2 tolerance at low and medium temperature is still a common direction. In this work, the CeFeW/ZrO2 catalyst prepared by a two-step hydrothermal method exhibited excellent SO2 resistance. The superior catalytic performance and SO2 tolerance of CeFeW/ZrO2 catalyst mainly originated from that Ce acted as a functional site to form Ce-O-Fe, which altered the local electronic environment through electron confinement effect, increased the proportion of Fe3+/(Fe2+ + Fe3+) and surface chemisorption oxygen as well as the formation of oxygen vacancies on the one hand. On the other hand, Fe sites exhibited excellent SO2 capacity and preferentially reacted with SO2, the metal sulfates Fe2(SO4)3 and FeSO4 restrained the formation and deposition of NH4HSO4 and (NH4)2SO4 on the catalyst surface. Simultaneously, the Ce-O-Fe-SO42- species ensured the electron transfer between Ce and Fe, and the redox properties of the catalyst were remained.