NO reduction by coal char was investigated in a fixed bed reactor using a simulated flue gas. Two different operation modes(programmed temperature and constant temperature) were employed to explore the mechanism of NO removal by coal char and to study the effects of the variables on NO removal efficiency and selectivity including temperature

coal type

NO and oxygen concentrations in flue gas and space velocity. The results indicated that surface complexes formed by chemisorption of NO and O2 on carbon active sites played the key role in reactions between C-NO and C-O2. XLHT coal char showed both the highest rate of NO reduction and C-NO selectivity among the coal chars studied. NO reduction by XLHT coal char could reach 99% at 723 K. Under the experimental conditions in this work

an increase in temperature and/or oxygen concentration in flue gas enhanced NO reduction. However

C-NO selectivity decreased with the increasing O2 concentration. Higher NO concentration in flue gas led to lower NO reduction but higher C-NO selectivity.