Gas Permeation Properties Of Graphene Oxide/Polymer Hybrid Membranes Prepared By In-Situ Polymerization

CO2capture is one of the most important subjects about energy and environment. Organic-inorganic hybrid membrane is a kind of promising gas separation membrane for CO2capture. However, organic-inorganic hybrid membrane for CO2capture is in an early development stage, its performance is not very high due to few membrane materials, poor dispersion of inorganic nanoparticles and the difficulty in structure control of membrane. In this paper, graphene oxide (GO) was added to the polymer membrane material, and a series of new membranes with remarkable gas permeation performance were developed.GO with different degrees of oxidation were synthesized using the harsh oxidation of graphite by the improved Hummers method. Then the structure of GO was characterized by TEM, AFM, XRD, FT-IR, XPS, Raman and SEM. Results showed that more polar functional groups were introduced to GO with the increase in oxidation degree of GO in the preparation process, producing fewer layers and more translucent structures (～0.8nm). GO with higher oxidation degree has significant effect on its dispersion in the N,N-dimethylacetamide solvent.GO/PU hybrid membranes and GO/PI hybrid membranes were successfully fabricated by in situ polymerization of Polymer monomers with GO. The effect of the addition of GO with different oxidation degrees on the morphologies and permeation performance of CO2, N2 gases of the hybrid membranes was evaluated by permeation experiments of CO2/N2gas mixture (volume ratio,1:9). Results showed that GO with higher oxidation degree has significant effect on its dispersion in the polymer hybrid membranes. However, excessive addition of GO into the polymer membranes would caused the aggregation of GO in the membranes. The appropriate amount of GO could significantly improve the permeability CO2and N2and the permeation selectivity of hybrid membranes. The permeability of hybrid membranes for CO2and N2increased. The CO2/N2permeation selectivity of membranes exhibited a trend of initial increase, followed by a decrease, with the increase in oxidation degree, when the same amount of GO was added. For GO with the same oxidation degree, the permeability and permeation selectivity of hybrid membrane initially increased, and then decreased with the addition content of GO.