International Journal of Hydrogen Energy, Vol.45, No.15, 8418-8432, 2020
Methane tri-reforming for synthesis gas production using Ni/CeZrO2/MgAl2O4 catalysts: Effect of Zr/Ce molar ratio
Three Ni/CeZrO2/MgAl2O4 catalysts synthesized using different Zr/Ce molar ratios (0.25, 1, and 4) were studied for methane tri-reforming. The catalysts were characterized using XRD, Al-27-NMR, H-2-TPR, CO2-TPD, XPS, and in situ techniques (XPD and XANES). The addition of CeZrO2 at Zr/Ce = 0.25 on the MgAl2O4 spinel support considerably reduced the amount of carbon deposits, because the methane decomposition reaction was attenuated by the presence of less agglomerated Ni-0 species produced after the reduction process. The highest CO2 adsorption capacity (basicity) was associated with the participation of medium-strength basic sites, which facilitated coke gasification and led to higher CO2 conversions. A syngas with quality (H-2/CO ratio) of 1.8 was produced, suitable for use in Fischer-Tropsch reactions. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.