A Novel UIO-66/Pebax® 1657 Mixed Matrix Membrane Exhibiting Superior CO2 Separation Performance via Nonthermal Air Plasma Modification

Abstract

This paper synthesized a new mixed matrix membrane for CO₂ separation. First, the metal-organic framework UIO-66 was treated with air plasma for modification and then embedded in Pebax® 1657. The 10% UIO-66/Pebax® 1657 mixed matrix membranes treated with air plasma significantly improved interfacial compatibility and CO₂ adsorption capacity, showing excellent performance. Its permeability reached 453 Barrer as CO₂ and the selectivity was 37.8 as CO₂/N₂. It was confirmed by characterization techniques such as FTIR, XRD, XPS, TGA, NMR, and SEM that the plasma successfully introduced ─NH₂ groups and active sites on the UIO-66 surface, thereby significantly improving the interfacial compatibility and adsorption characteristics of the mixed matrix membrane. In this study, the high-performance CO₂ separation membrane aP-UIO-66/Pebax was innovatively enhanced through the synergistic effects of graft modification and defect engineering on UIO-66 using nonthermal plasma technology. This approach offers a novel strategy for membrane performance optimization.