Study on simultaneous removal of SO2 and NOx from sintering flue gas over Fe-Mn/AC catalyst

Abstract

In this work, activated coke catalysts were modified with Fe or/and Mn oxides using an impregnation method. The catalysts were thoroughly characterized using various techniques, including XRD, SEM, XPS, TG-DSC and H2-TPR. The effects of Fe and Mn oxides modification on the catalytic performance of AC catalysts for simultaneous removal of SO2 and NOx were studied. The results showed that Fe-Mn/AC catalyst presented excellent catalytic activity for both SO2 and NOx. The co-doping of Fe and Mn oxides resulted in the formation of the microporous structures, which served as active reaction sites on the catalyst surface. The carbonyl group (CO) was found to play an active role in the oxidation of SO2 by forming a hydrogen bond, which reduced the energy barrier for the conversion of SO2 to SO3. Moreover, it was observed that the deposition of MnSO4/FeSO4 over Fe-Mn/AC catalyst was lower than that of Fe/AC and Mn/AC catalysts. Finally, a possible mechanism model for the denitrification and desulfurization processes over Fe-Mn/AC catalyst was proposed.