Abstract
TiO2 with different iron and manganese oxides adding orders were prepared through isovolumetric impregnation and tested for catalytic oxidation of NO with O-2. It was found that the sampleobtained from one-step impregnation method had better catalytic activity. The excellent activity wasattributed to higher surface area, lower crystalline of manganese oxides, abundant Mn3+, Fe3+ and chemisorbed oxygen species on the surface. Furthermore, effects of loading sequences on FeMnOx/TiO2 catalysts were investigated. The study showed that Fe and Mn would affect each other and change thesurface physicochemical properties of FeMnOx/TiO2 when they were loaded step-by-step. In addition, the inhibiting effect of H2O on catalytic activity was reversible while the conversion of NO recoveredto 40% when SO2 was cut off. XPS analysis between used and fresh catalysts revealed the electrontransfer between Fen+ and Mnn+ ions in FeMnOx/TiO2. Possible reaction mechanism was put forward by comprehensive analysis of XPS and FT-IR results. (C) 2014 Elsevier B.V. All rights reserved.