The Properties And Scr De-Nox Application Of Supported V2o5/Tio2 Catalysts With Different Polymerization State Of Vox Species Controlled By The Ph Value Of Their Precursors

NOx is the main pollutant in the air, which causes many harmful effects on society. The V2O5/TiO2 catalysts are very important to reduce the NOx from the heat engine plants and vehicle exhausts. However, various reasons will affect the performance of the catalysts. In this paper, the polymerization state of surface VOx of supported V2O5/TiO2 catalysts was controlled by changing the pH value of the impregnation precursor solutions, and the redox and acidity properties of the catalysts can be adjusted consequently. The Raman spectroscopy, V-51 magic-angle spinning nuclear magnetic resonance (MAS NMR), H-2-temperature-programmed reduction (H-2-TPR), NH3-temperature-programmed desorption (NH3-TPD), NH3-temperature-programmed oxidation (TPO) and (NH3)-N-15-NO-O-2-temperature-programmed surface reaction (TPSR) were mainly used for the characterization and properties tests of the samples. Although all catalysts in this work had similar surface morphology and the same vanadium loading, the catalyst oxidability decreased while acidity increased with the increasing of VOx polymerization, which causes the NO conversion increases with the increasing of VOx polymerization below 300 degrees C in selective catalytic reduction (SCR) de-NOx reaction. This work will promote the advance in catalysis and anti-pollution fields for human and nature.