نوع مقاله : پژوهشی
نویسندگان
1 اصفهان، دانشگاه صنعتی اصفهان، دانشکده مهندسی نساجی، کد پستی 8415683111
2 سبزوار، دانشگاه حکیم سبزواری، دانشکده مهندسی نفت و پتروشیمی، گروه مهندسی پلیمر، کد پستی 9617976487
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Hypothesis: The morphology of flat membranes, as one of the determining factors, plays a fundamental role in their functional properties, including permeability, selectivity, and mechanical strength. Precise adjustment of surface structure and membrane porosity enables optimization of separation processes and leads to significant improvements in efficiency and performance in industrial applications. Specifically, in the water and wastewater industry, controlling membrane morphology enhances fouling resistance and increases the operational lifetime of membranes.
Methods: In this study, an asymmetric poly(vinylidene fluoride) (PVDF) flat membrane was fabricated using the wet-casting method. To analyze the resulting morphology, a comprehensive kinetic and thermodynamic investigation of the polymer solutions was conducted to identify and explain the mechanisms governing the formation of the different layers in the asymmetric PVDF membrane structure.
Findings: Investigation of field-emission scanning electron microscopy (FESEM) images revealed that the upper surface (active layer), cross-section, and bottom surface of the membrane exhibited distinctly different morphologies. These differences were attributed to the thermodynamic behavior and mass transfer pathways within the various layers of the cast film. ATR-FTIR results further demonstrated that morphological changes in the membrane led to microstructural variations on the upper and bottom surfaces, ultimately strengthening the β-phase in the PVDF polymer chains at the bottom surface. In addition, contact angle measurements showed that the water contact angle on the upper surface was 90°, whereas on the bottom surface it was 101°. Overall, it can be concluded that a precise understanding of the mechanisms governing the formation of different layers in asymmetric flat membranes enables control over the physical and chemical properties of the membrane surface, a goal partially achieved in this study.
کلیدواژهها [English]
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