Abstract Bio-butanol is an important aspect for development of renewable energy. Currently, it remains challenging for developing highly permeable and selective composite membranes to efficiently recover butanol produced in biomass fermentation process. In this work, we fabricated polydimethylsiloxane (PDMS) into thin and defect-free composite membranes by using porous PVDF as the substrate. The formation of PDMS membrane layer was finely controlled by optimizing the substrate pore size and casting solution viscosity. In particular, the interfacial adhesion between PDMS active layer and PVDF substrate layer, which is critical for practical application of composite membrane, was probed by using in-situ nano-indentation/scratch technique for the first time. The transport properties of the prepared PDMS/PVDF composite membranes were studied by pervaporation recovery of n-butanol from aqueous solution with different feed concentrations or temperatures. The results indicated that the PDMS membrane layer with a carefully tuned thickness of ∼11 μm offered high total flux of 2210 g/m2h and excellent separation factor of 46 (1 wt% butanol/water at 70 °C), as well as strong interfacial adhesion for the PDMS/PVDF composite membrane. The separation performance is superior to the reported membranes, showing great potential for application in bio-butanol separation.

中文翻译：

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优化用于从水溶液中回收丁醇的 PDMS/PVDF 复合膜的分离性能和界面附着力

摘要 生物丁醇是发展可再生能源的重要方面。目前，开发高渗透性和选择性复合膜以有效回收生物质发酵过程中产生的丁醇仍然具有挑战性。在这项工作中，我们通过使用多孔 PVDF 作为基材将聚二甲基硅氧烷 (PDMS) 制成薄且无缺陷的复合膜。通过优化基材孔径和浇铸溶液粘度来精细控制 PDMS 膜层的形成。特别是，首次使用原位纳米压痕/划痕技术探测了对复合膜的实际应用至关重要的PDMS活性层和PVDF基底层之间的界面粘附。通过从不同进料浓度或温度的水溶液中渗透蒸发回收正丁醇，研究了制备的 PDMS/PVDF 复合膜的传输性能。结果表明，经过精心调整的厚度约为 11 μm 的 PDMS 膜层提供了 2210 g/m2h 的高总通量和 46 的出色分离因子（70 °C 下 1 wt% 丁醇/水），以及强界面PDMS/PVDF 复合膜的附着力。分离性能优于报道的膜，显示出在生物丁醇分离中的巨大应用潜力。结果表明，经过精心调整的厚度约为 11 μm 的 PDMS 膜层提供了 2210 g/m2h 的高总通量和 46 的出色分离因子（70 °C 下 1 wt% 丁醇/水），以及强界面PDMS/PVDF 复合膜的附着力。分离性能优于报道的膜，显示出在生物丁醇分离中的巨大应用潜力。结果表明，经过精心调整的厚度约为 11 μm 的 PDMS 膜层提供了 2210 g/m2h 的高总通量和 46 的出色分离因子（70 °C 下 1 wt% 丁醇/水），以及强界面PDMS/PVDF 复合膜的附着力。分离性能优于报道的膜，显示出在生物丁醇分离中的巨大应用潜力。