Influence of Polyethylene Glycol on the Catalytic Activity of MnFeOx for NO Oxidation at Low-Temperature

MnFeOx catalysts were prepared by organic solvent method, and the effect of different proportion of polyethylene glycol (PEG) on selective catalytic oxidation (SCO) reaction performance was investigated. The results showed that the activity of the catalyst increased first and then decreased with the increase of the proportion of PEG. The MnFeOx (PEG=0.3%) catalyst had better SCO catalytic activity at low temperature. The catalyst was characterized by Brunauer-Emmett-Teller, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction by hydrogen (H-2-TPR) and temperature-programmed desorption by oxygen (O-2-TPD). The results indicated that dual function of pore-forming and stable adhesion of PEG increased the dispersion of ferromanganese oxide on the surface of the MnFeOx catalyst, thereby improving the activity of the catalyst. When the proportion of PEG was more than 0.3%, the catalyst was agglomerated and MnO2 was largely converted to Mn2O3. The results of H-2-TPR and O-2-TPD tests indicated that the appropriate addition of PEG was beneficial to improve the reduction performance of the catalyst and the desorption performance of the surface chemical adsorption O2-. [GRAPHICS] .