The promotional effect of MnOx on (NH4)2S2O8-modified activated coke for selective catalytic reduction of NO with NH3 at low temperature

Abstract In this study, Manganese oxide (MnOx) was supported on activated coke modified by (NH4)2S2O8 (ACs) to obtain novel MnOx/ACs catalysts with high NOx removal performance by excessive impregnation method. The influence of precursor and loading amount of MnOx on the catalytic efficiency were studied. The Mn3O4 supported on ACs samples prepared with manganese acetate tetrahydrate as precursor and the loading amount of 8% Mn is the most effective in NOx removal among modified samples and its removal efficiency is 97% at 180 °C. And the adsorption state and reaction behaviors of NH3, NO and O2 on MnOx/ACs catalysts were measured by in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) in different conditions in order to study the effect of MnOx and the reaction mechanism. The results suggested that Eley-Rideal and Langmuir-Hinshelwood mechanism existed simultaneously for the selective catalytic reduction of NO over the MnOx/ACs catalyst.