Microwave-Assisted Temperature Swing for Integrated CO ₂ Capture and Dry Reforming of Methane

Syngas production from CO 2 is critical to the efficient production of sustainable aviation fuel via the Fischer–Tropsch and methanol-to-jet processes. While integrating CO 2 capture and conversion with dry reforming of methane (DRM) is a promising approach, it requires optimization of the temperature conditions of each reaction step. In this study, we evaluated the effectiveness of temperature swing operation using a microwave setup, which enables rapid temperature swing with potentially lower energy input than that required by conventional heating. To determine the optimal temperature for each reaction step, the kinetics of CO 2 capture and steady-state DRM were examined separately under conventional heating conditions using a Ca–Ni-based dual function material as a CO 2 sorbent and catalyst. Experimental and numerical analyses indicated that intermediate temperatures between 600 and 650 °C are optimal for CO 2 capture, whereas higher temperatures are favorable for facilitating the endothermic DRM reaction. Through temperature swing operation between 600 (CO 2 capture) and 700 °C (DRM), integrated CO 2 capture and DRM under microwave heating produced 5.50 mmol/g CO, which is 1.5-fold higher than the maximum amount obtained under isothermal conditions. These findings demonstrate the effectiveness of microwave heating with temperature swing operation, representing an important step toward the practical implementation of integrated CO 2 capture and DRM for syngas production.