Preparation of active coke combining coal with biomass and its denitrification performance

To improve the selective catalytic reduction of NO with NH3 over active coke (AC), coal–biomass ACs were prepared from the mixture of poplar and 1/3 coking coal for increasing the active sites. The resultant ACs were characterized by N2 adsorption and X-ray photoelectron spectroscopy. Furthermore, the denitrification performance was tested at laboratory scale. In addition, density functional theory was used to analyze active sites on the surface of AC. The result revealed that, with an increase in poplar content, the decrease in micropores volume appeared in the reduction of denitrification space. However, C−O group including hydroxyl and ether increased with the increase in poplar content, which was found to be most likely responsible for the promoted catalytic activity of AC toward NO reduction mainly because of enhancing NH3 adsorption. The comprehensive effect of two factors made the denitrification ability of AC increased first and then decreased.