In the last decades improving the performance of polymeric membranes, for example adding inorganic nanoparticles in polymer matrix is one of the predominant concerns of the researchers. In the present work, the separation of oxygen, nitrogen, methane and carbon dioxide gases by PVC/silica nanocomposite membranes were investigated. Silica nanoparticles were prepared via sol-gel method. Membranes were prepared by thermal phase inversion method. The prepared nanocomposite membranes were characterized using FTIR, SEM and TGA methods. The results demonstrate a nano-scale and good distribution of silica particles in the polymer matrix. This confirms the desirable mixing of the silica in polymer and also a good compatibility between the two phases. The thermal properties of PVC membranes were also improved by adding silica particles. The performances of prepared membranes in gas separation were measured at pressure of 10 barg and temperature of 25 ◦C. The obtained results showed that the permeability of all gases increased. Also by entering silica nanoparticles in PVC matrix, the performances of separation of CO2 from CH4 and separation of CO2 from N2 were increased.

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