The 4% Ni-Al2O3catalysts prepared by coprecipitation method calcined at different temperature was tested by propane selective catalytic reduction of nitric oxide（NO） in excess oxygen.Catalyst calcined at 550 ℃ showed the highest activity for selective catalytic reduction of NO and the NO conversion was approached to 100 % at 500 ℃.The Ni-Al2O3 catalyst was characterized by XRD,temperature-programmed reduction with H2(H2-TPR) and BET techniques.Based on the characterization results,with the increase of calcinations temperature,NiO gradually changes to the surface aluminate phase containing highly dispersed nickel metal cations in Al2O3 matrix,which was responsible for the high activity of catalyst calcined at 550 ℃.At higher calcination temperature,the decrease of surface areas results in the decrease of the activities of the catalyst for NO selective catalytic reduction by propane.
