Methane tri-reforming for synthesis gas production using Ni/CeZrO2/MgAl2O4 catalysts: Effect of Zr/Ce molar ratio

Abstract

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, 27Al-NMR, H2-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 Ni0 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 (H2/CO ratio) of 1.8 was produced, suitable for use in Fischer-Tropsch reactions.