Analysis of CO₂ utilization into synthesis gas based on solar thermochemical CH₄-reforming

In this study, the solar thermochemical reactor performance for CO₂ utilization into synthesis gas (H₂ + CO) based on CH₄ reforming process was investigated in the context of carbon capture and utilization (CCU) technologies. The P1 radiation heat transfer model is adopted to establish the heat and mass transfer model coupled with thermochemical reaction kinetics. The reactor thermal behavior with direct heat transfer between gaseous reactant and products evolution and the effects of different structural parameters were evaluated. It was found that the reactor has the potential to utilize by ∼60% of CO₂ captured with 40% of CH₄ co-fed into syngas (72.9% of H₂ and 27.1% of CO) at 741.31 kW/m² of incident radiation heat flux. However, the solar irradiance heat flux and temperature distribution were found to significantly affect the reactant species conversion efficiency and syngas production. The chemical reaction is mainly driven by the thermal energy and higher species conversion into syngas was observed when the temperature distribution at the inner cavity of the reactor was more uniform. Designed a solar thermochemical reactor able to volumetric store concentrated irradiance could highly improve CCU technologies for producing energy-rich chemicals. Besides, the mixture gas inlet velocity, operating pressure and CO₂/CH₄ feeding ratio were crucial to determining the efficiency of CO₂ utilization to solar fuels. Catalytic CO₂-reforming of CH₄ to chemical energy is a promising strategy for an efficient utilization of CO₂ as a renewable carbon source.