A novel Ce–Sb binary oxide catalyst for the selective catalytic reduction of NOx with NH3

Abstract

A series of Ce–Sb binary oxide catalysts prepared by the citric acid method have been investigated for the selective catalytic reduction (SCR) of NO_x with NH₃. It was found that the Ce–Sb oxide catalysts showed excellent NH₃-SCR activity and a high tolerance to H₂O and SO₂ in a wide operation temperature window. N₂-adsorption, X-ray diffraction (XRD), Raman spectroscopy, H₂ temperature programmed reduction (H₂-TPR), NH₃ temperature programmed desorption (NH₃-TPD), X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were conducted to correlate the catalyst structure and surface properties to the catalytic performance of Ce–Sb binary oxide catalyst. The strong interaction between Sb and Ce species not only enhances the redox property of the catalyst but also increases the surface acidity, thus promoting the adsorption and activation of NH₃ species, which is favorable for high NH₃-SCR performance.