Effects of CrOx species doping on V2O5-WO3/TiO2 catalysts on selective catalytic reduction of NOx by NH3 at low temperature

作者：Chen, Mengyin; Wei, Xaixia; Liang, Jun; Li, Shencheng; Zhang, Zhe; Tang, Fushun^*

来源：Reaction Kinetics Mechanisms and Catalysis, 2022, 135(4): 1767-1783.

DOI：10.1007/s11144-022-02252-4

• V2O5-WO3
• TiO2 catalyst
• Cr2O3 doping
• Dispersion structure
• SCR

In this paper, the lower-temperature (200 degrees C) SCR performance of modulated 1%V2O5-5%WO3/TiO2 catalysts with different Cr2O3 amount was investigated. Results showed that addition of an appropriate amount of Cr2O3 component (< 5 wt%) can improve the NO reaction rate constant k of modulated VW/Cr/Ti catalysts with forming lower N2O concentration. The interaction between VOx or WOx species and CrOx species reduced the degree of polymerization of VOx and WOx species, thus promoting the formation of V-O-W bonds. The formation of V-O-Cr and V-O-W bonds increased the redox type of VOx and the amount of B acid, so the doping of Cr2O3 (< 5 wt%) improved the catalytic performance of V2O5-WO3/TiO2 catalyst. After excessive Cr2O3 (> 5 wt%) was added, the crystal phase Cr2O3 was formed, which weakened the formation of V-O-W and V-O-Cr bonds, and promoted the oxidation of NH3, thereby reducing the catalytic activity. In addition, Cr2O3 modified V2O5-WO3/TiO2 still had a high catalytic activity, high stability, and low N2O generation under the reaction conditions of 10% H2O and 100 ppm SO2.

• 单位
  桂林理工大学; 南京大学