Syngas production from CO₂ reforming of methane over neodymium sesquioxide supported cobalt catalyst

This paper reports for the first time the catalytic dry (CO₂) reforming of methane over 20 wt%Co/80 wt%Nd₂O₃ catalyst. The catalyst was synthesized by wet-impregnation procedure and its physicochemical properties were characterized by TGA, XRD, FESEM, EDX, FTIR, H₂-TPR and TPD followed by activity testing in a fixed-bed reactor. The effects of feed ratios (CH₄: CO₂) ranged 0.1–1.0, reactant (CH₄ and CO₂) partial pressure (0–50 kPa) and temperature ranged 923–1023 K on the activity of the catalyst were investigated. The conversion of both reactants increased with the feed ratio and reaction temperature reaching maximum values of 62.7% and 82% for CH₄ and CO₂, respectively. The CO₂ reforming of methane resulted into the formation of syngas with maximum yields of 59.91% and 62.02% for H₂ and CO, respectively, leading to formation of syngas ratio of 0.97. The mechanistic proposition includes the CH₄ and CO₂ adsorption, activation of CH₄ by methane cracking and gasification of carbon deposited on the catalyst surface. The experimental data were fitted by Langmuir Hinshelwood kinetic models. Activation energy values of 21.89 and 62.04 kJ mol⁻¹ were obtained for the consumption of CO₂ and CH₄ respectively from Langmuir-Hinshelwood models. The lower values of activation energy obtained for CO₂ compared to that of CH₄ shows that the rate of consumption of CO₂ was faster than that of CH₄ leading to higher conversion of CO₂.