Highly Efficient Mesoporous V.sub.2O.sub.5/WO.sub.3-TiO.sub.2 Catalyst for Selective Catalytic Reduction of NO.sub.x: Effect of the Valence of V on the Catalytic Performance

• Published in: Catalysis Surveys from Asia Vol. 21; no. 3; p. 103
• Main Authors: Zong, Luyao, Dong, Fang, Zhang, Guodong, Han, Weiliang, Tang, Zhicheng, Zhang, Jiyi
• Format: Journal Article
• Language: English
• Published: Springer 01.09.2017
• ISSN: 1571-1013; 1571-1013
• DOI: 10.1007/s10563-017-9229-y

Mesoporous WO.sub.3-TiO.sub.2 support was synthesized by hydrothermal method, mesoporous V.sub.2O.sub.5/WO.sub.3-TiO.sub.2 catalyst was synthesized by impregnation method and used for selective catalytic reduction (SCR) of NO.sub.x with a excellent NO.sub.x conversion at a wider operating temperature ranging from 200 to 460 °C. In the range of 260-440 °C, NO.sub.x conversion reached to 98.6%, and nearly a complete conversion. Even with the existence of 300 ppm SO.sub.2, NO.sub.x conversion was only a little decline. The catalyst was characterized by a series of techniques, such as XRD, BET, XPS, TEM, Raman and H.sub.2-TPR. It was concluded that V.sub.2O.sub.5/WO.sub.3-TiO.sub.2 catalyst was ascribe to antase TiO.sub.2, and also the high crystallinity of anatase TiO.sub.2 could improve the SCR performance. More interested, V.sub.2O.sub.5/WO.sub.3-TiO.sub.2 catalyst exhibited the typical mesoporous structure according to the BET results. In addition, the TEM results indicated that the active components of V and W were well-dispersed on the surface of TiO.sub.2, while the enhancement of dispersion could improve the activity of catalysts. More importantly, the concentration ratio of V.sup.4+/(V.sup.5+ + V.sup.4+ + V.sup.3+) performed the key role in improving the activity of V.sub.2O.sub.5/WO.sub.3-TiO.sub.2 catalyst.