Comprehensive understanding of the superior performance of Sm-modified Fe2O3 catalysts with regard to NO conversion and H2O/SO2 resistance in the NH3-SCR reaction

Sm-doped Fe2O3 catalysts, with a homogeneous distribution of Sm in nanoparticles, were synthesized using citric acid-assisted sol-gel method. Kinetic studies show that the reaction rate for NOx reduction optimal catalyst (0.06 mol% doping Fe2O3) was nearly 11 times higher than pure Fe2O3, when calculated based on specific surface area. Furthermore, Fe0.94Sm0.06Ox maintains > 83% conversion 168 h at high space velocity presence SO2 and H2O 250 °C. A substantial amount surface-adsorbed oxygen generated Fe0.94Sm0.06Ox, which promoted NO oxidation subsequent fast between NH3. The adsorption activation NH3 also enhanced by doping. In addition, facilitated decomposition NH4HSO4 resulting its activity stability + H2O.