Synthesis Gas Production via Dry Reforming of Methane over Manganese Promoted Nickel/Cerium-Zirconium Oxide Catalyst

Nickel/cerium-zirconium oxide (Ni/Ce50-Zr50) and manganese promoted Ni/Ce50-Zr50 (Ni-Mn/Ce50-Zr50) catalysts were prepared using an impregnation method and used in the dry reforming of methane. The catalysts were characterized by H-2 temperature-programmed reduction, transmission electron microscopy, X-ray photoelectron spectroscopy, CO2 temperature-programmed desorption, X-ray diffraction, in situ diffuse reflectance infrared Fourier transform spectra, and thermogravimetric analysis. A manganese promoter facilitated the formation of the reaction intermediate-CH2OH species at low temperature. A synergistic effect between Ni and Mn species enhanced the adsorption of CO2 on Ni-Mn/Ce50-Zr50. A manganese promoter not only enhanced the catalytic activity but also led to a high H-2/CO ratio product. At 600 degrees C, under atmospheric pressure, with 20 000 h(-1) gas hourly space velocity and CH4/CO2/Ar = 1:1:8, on a Ni-Mn/Ce50-Zr50 catalyst, the CH4 conversion (38.7%), CO2 conversion (40.4%), and the H-2/CO ratio (0.83) were all much higher than those on both nonpromoted Ni/Ce50-Zr50 and SiO2 supported Ni-Mn catalysts.