Development of Plasma Swing Adsorption Process Using Reduced CeO ₂ for Efficient CO ₂ Removal in H ₂ Purification

The effective removal of low-concentration CO2 is a key challenge for purification processes. This work develops a novel plasma swing adsorption (PLSA) process using chemisorbents to enable efficient regeneration under mild conditions. We found that reducing CeO2 enhanced its CO2 adsorption in the H2 stream while the resulting chemisorbed species became unstable under plasma. Fixed-bed desorption experiments confirmed that dielectric barrier discharge (DBD) plasma not only induced CO2 desorption but also converted it into CH4 and CO, achieving a faster desorption rate and integrating CO2 removal with utilization. Consequently, we established a PLSA cycle under ambient conditions, alternating between adsorption (plasma off) and desorption (plasma on). This study paves the way for carbon-neutral capture processes with low energy consumption.