Selective catalytic reduction of NO by CO over α-Fe2O3 catalysts

•Denitrification with CO as reducing agent has various advantages.•α-Fe2O3 is cheap and simple to produce, and can be used as a catalyst to effectively reduce costs.•The effect of crystallinity on the reaction is presented by comparing the catalysts prepared by different methods.•All three catalysts have 100 % activity at temperatures above 250 °C.