Investigating the State of Skin Layer of Asymmetric Polyethersulfone (PES) - Zeolitic Imidazole Framework-8 (ZIF-8) Mixed Matrix Gas Separation Membranes and Its Effect on Gas Separation Performance

Tüzün Antepli, Burcu
Yılmaz, Levent
Kalıpçılar, Halil
© 2022 Wiley-VCH GmbH.Asymmetric and dense polyethersulfone (PES) and PES/ZIF-8 (Zeolitic Imidazole Framework-8) membranes were produced by nonsolvent induced phase inversion and solvent evaporation, respectively. The skin layer on the asymmetric membranes was prepared intentionally thick to observe the distribution of ZIF-8 and interfacial voids between ZIF-8 and PES, and to compare the state of ZIF-8 in the asymmetric membranes with that of in dense membranes prepared by solvent evaporation. All asymmetric membranes were prepared only by wet phase inversion to eliminate the effect of solvent evaporation on the skin layer morphology. For this purpose, the effect of composition of solvent and nonsolvent bath, ZIF-8 percentage and particle size was investigated. The skin layer on asymmetric and dense membranes prepared by SE (solvent evaporation) had very similar morphologies, CO2/CH4 and H2/CH4 ideal selectivities, however, the single gas permeabilities through asymmetric membranes were higher. This was attributed to the influence of ZIF-8 on the structure of continuous polymeric phase.


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Citation Formats
B. Tüzün Antepli, L. Yılmaz, and H. Kalıpçılar, “Investigating the State of Skin Layer of Asymmetric Polyethersulfone (PES) - Zeolitic Imidazole Framework-8 (ZIF-8) Mixed Matrix Gas Separation Membranes and Its Effect on Gas Separation Performance,” ChemistrySelect, vol. 7, no. 21, pp. 0–0, 2022, Accessed: 00, 2022. [Online]. Available: