Integration of Membrane Separation with Non-Thermal Plasma (NTP) Catalysis: A Proof-of-Concept for CO2 Capture and Utilisation (CCU)

Carbon dioxide (CO2) capture and utilisation (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 non-thermal 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 MS and Ni/NaBETA and Ni/UiO-66 catalyst in NTPR). Upon optimisation, the hybrid MS-NTPR system showed satisfactory carbon capture efficiency (CCE) and carbon utilisation 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.