The Study of the MnOx/TiO₂-ZrO₂ Used in the Sintering Flue Gas Low-Temperature Selective Catalytic Reaction

Abstract:

TiO₂, 50%TiO₂-ZrO₂ and 80%TiO₂-ZrO₂ were prepared by sol-gel method. The manganese oxides were impregnated on the carrier and the catalysts were used for low-temperature selective catalytic reduction of NOx with ammonia (NH₃-SCR) in the presence of excess O₂. The samples were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results showed that the particle size of 80%TiO₂-ZrO₂ is the smallest among the three kind of carrier and the particles are highly dispersed. By adding the ZrO₂, the Zr⁴⁺ ions replaced the lattice Ti⁴⁺ ions, and thus caused lattice distortion in the TiO₂ and an increase of the active point amount on the carrier. Furthermore, the Zr also promoted the dispersion of the active ingredients carried on the carrier, increased the surface concentration of Mn. The most active catalyst was obtained with a mass MnOx/80%TiO₂-ZrO₂ ratio of 0.1.The best MnOx/80%TiO₂-ZrO₂ catalyst yielded nearly 92.6% NO conversion at 130°C at a high space velocity of 67,000 h^-1.

• Periodical: Advanced Materials Research (Volumes 641-642)
• Pages: 551-556
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.641-642.551
• Online since: January 2013
• Authors: Xi Ning Lu, Cun Yi Song
• Keywords: Low Temperature SCR, Manganese Oxide, NO Conversion, Sol-Gel (SG), TiO₂-ZrO₂

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