DRIFT Study on Cr2O3-SO42-/TiO2 Catalyst for Low Temperature Selective Catalytic Reduction of NO with NH3

Chromium oxides supported on TiO₂ showed good activity for the selective catalytic reduction of NO by NH₃. The catalytic activity of Cr₂O₃-SO₄^2-/TiO₂ catalyst was greatly enhanced by the addition of SO₄^2- into TiO₂ support. The catalyst surface properties were characterized with NH₃-TPD(temperature programmed desorption) and H₂-TPR(temperature programmed reduction). The sulphate on the catalyst surface could enhance the acidity and redox of the catalyst obviously. The reaction mechanism on this catalyst was researched in detail by in situ diffuse reflectance Fourier transform infrared(FTIR) spectroscope. Eley-Rideal and Langmuir-Hinshelwood mechanism existed simultaneously for selective catalytic reduction(SCR) reaction of NO over Cr₂O₃-SO₄^2-/TiO₂ catalyst.