Multi-stage spiral-type structured catalyst system for direct large-scale methanation of industrial CO2 emissions: a feasibility study†

Anthropogenic CO₂ emission to the atmosphere has led to severe climate changes and global warming worldwide. The conversion of CO₂ into value-added products is an important and promising solution to reduce the atmospheric levels of CO₂ and overcome the energy crisis. The CO₂ methanation reaction is being explored by many researchers and industries for the fixation of CO₂ as a power-to-gas technology. In this report, we have attempted CO₂ methanation in the presence of O₂ using a lab-scale two-stage type reactor system with Ni and Ru-based spiral-type structured catalysts. Furthermore, the thermodynamic properties of both catalysts were evaluated in the presence and absence of O₂. The combustion of H₂ due to the coexistence of O₂ promoted methanation even under room temperature conditions and showed excellent methanation performance (conv. 90% & selectivity 100%) for relatively larger amounts (5 L min⁻¹) of gas treatment. Additionally, the heat management for the reactors by adiabatic insulation was found to be effective in improving the catalytic performance and thermodynamic properties.