Modification of Nano Spherical-Like MnO_x/TiO₂ Catalysts with F-Doped

Abstract:

A series of spherical-like MnO_x/TiO₂ catalysts with F-doped were prepared by using sol-gel method and investigated for low-temperature selective catalytic reduction (SCR) of NO_x with NH₃ at the temperature ranging from 100 °C to 200 °C. The 0.07Ce-MnO_x/TiO₂ catalyst shows the highest activity and yields 95% NO conversion at 200 °C. With the help of XRD, TGA, H₂-TPR, NH₃-TPD, BET and TEM, the structures and properties of the catalysts were characterized. The results show that it is a fine modifier for TiO₂ support with appropriate amounts of F doping, and F ions can enter into TiO₂ lattice, reducing the formation of rutile TiO₂ and the crystallization of MnO_x. However, MnTiO₃ was generated in the catalysts with excess F doping. This would cause larger diameter of spherical particle and smaller surface area. But the amounts of the surface acid sites increased, and the reduction ability of catalysts was enhanced, which is beneficial for catalytic activity of the catalysts.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 1896-1904
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.1896
• Online since: June 2017
• Authors: Jun Lin Xie, Feng Xiang Li, Hai Feng Cui, Feng He*, Kai Qi
• Keywords: F Modified, Low-Temperature SCR, MnO_x/TiO₂ Catalysts

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