Integration of Membrane Separation with Nonthermal Plasma Catalysis: A Proof-of-Concept for CO₂ Capture and Utilization

Carbon dioxide (CO₂) capture and utilization (CCU) plays an important role in abating carbon emissions, mitigating global warming, and converting CO₂ as feedstock to value-added fuels and chemicals. Herein, a proof-of-concept study of a novel integrated process, consisting of a membrane separator (MS) followed by a nonthermal plasma reactor (NTPR) in tandem, was presented and systematically investigated, as an efficient platform, for potential applications in CCU. Specifically, biogas upgrading via CH₄ enrichment was used as the model system to investigate the proposed integrated system (using SAPO-34 zeolite membrane in a MS and Ni/NaBETA and Ni/UiO-66 catalyst in the NTPR). Upon optimization, the hybrid MS-NTPR system showed satisfactory carbon capture efficiency (CCE) and carbon utilization efficiency (CUE) of ca. 91.8% and 71.7%, respectively. In addition, the integrated process also exhibited excellent stability for CCU in upgrading synthetic biogas with a stable performance over a 40-h longevity test. This work, for the first time, showed the feasibility of using the novel integrated process for effective CCU.