A novel chemical looping strategy is proposed to enhance CO₂ utilization via methanation, enabling the production of high-purity CH₄. The process relies on a temperature-swing system using MgO as a CO₂ sorbent: CO₂ is captured at low temperature, then released at higher temperature and directly hydrogenated over a Ni-based catalyst. Operated in a cyclic fixed-bed reactor, the system leverages the thermal synergy between endothermic desorption and exothermic methanation.
A one-dimensional dynamic reactor model was developed in MATLAB, incorporating mass, energy, and momentum balances along with kinetics for adsorption, desorption, and methanation to capture transient behavior. Both isothermal and non-isothermal conditions were studied to assess thermal effects and energy integration. Sensitivity analyses on key parameters (e.g., temperature, GHSV, and bed composition) show that this approach can effectively integrate CO₂ capture and conversion in a single unit, reduce external energy demand, and improve overall efficiency, supporting the development of advanced dynamic chemical looping systems.