화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.58, No.4, 1760-1768, 2019
Effect of Promoters on the Catalytic Performance and SO2/H2O Resistance of alpha-MnO2 Catalysts for Low Temperature NH3 -SCR
A series of alpha-MnO2 catalysts doped with Fe, Ce, Cr, Zr, or Co as metal promoters were synthesized via a hydrothermal method. The effects of these metal promoters on the physicochemical properties and deNO(x) activity of the alpha-MnO2 catalysts were systematically investigated, among which alpha-MnO2 catalyst doped with Co behaved with the best selective catalytic reduction (NH3-SCR) activity at low temperatures. The alpha-MnO2 catalyst with Mn/(Mn + Co) = 0.8 (molar ratio) displayed an outstanding NH3-SCR activity with 100% NO conversion between 140 and 280 degrees C, excellent N-2 selectivity and stability which may be due to plenty of acid sites, a strong adsorption capacity for NH3/NO at 100-300 degrees C, and abundant Mn4+, Co3+, and surface adsorbed oxygen species. Further, the catalyst exhibited excellent H2O/SO2 resistance and the NO conversion activity remained 100% after adding 5% H2O, 200 ppm of SO2, or 5% H2O + 100 ppm of SO2 at 200 degrees C.