Effect of Cu–Mo Activities on the Ni–Cu–Mo/Al2O3 Catalyst for CO2 Reforming of Methane

Abstract

A series of Ni–Cu–Mo/Al2O3 catalysts with different metal contents were prepared by sequential impregnation method. The performance of the catalysts for carbon dioxide reforming of methane was investigated in a quartz tubular reactor at CH4/CO2 ratio of 4/6, feed gas flux of 100 mL/min, catalysts 460 mg, temperature range of 600–900 °C and atmospheric pressure. The catalysts were characterized by XRD, XPS, BET, CO2-TPD, TG, EDS and SEM. The performance and characterization results showed that the addition of Cu and Mo was beneficial for the reaction. The formation of spinel (NiMoO4, NiAl2O4, Cu6Mo4O15) and alloy (Ni3Mo, Cu3.8Ni) structures could significantly improve the catalytic activity and prevent the generation of carbon deposition. XRD patterns of the catalyst with the mass ratio of Ni:Mo = 0.75 after reaction suggested Mo2C formation which could eliminate the coke and extend the stability. The catalyst with the mass ratio of Ni:Mo = 0.75 showed better activity and still remained highly active under the condition of 800 °C for 60 h. Therefore, the highly effective Ni–Cu–Mo/Al2O3 catalyst could be a potential catalyst for carbon dioxide reforming of methane.