The application of materials with selective superwettability to oil/water separation has attracted much attention due to frequent oil spills, large discharges of oily wastewater and many shortcomings of traditional separation methods. Herein, we successfully prepared double-defense membranes by co-precipitating dopamine hydrochloride and polyvinyl polyamine on the original commercial hydrophilic polyvinylidene fluoride (PVDF) membrane and coating the membrane with a halloysite-based hydration layer. Our membranes are highly efficient (>99.6 %) in separating oil-in-water emulsions, have outstanding recycle capacity, good anti-fouling properties (underwater oil contact angle of 156.6 ± 1.9°, low oil adhesion), and are resistant to acid, alkali, and salt. Besides, our membranes can also remove different dye solutions through simple filtration. With the advantages of double-defense design, excellent underwater oleophobic performance in various environments, oil–water emulsion separation performance, dye removal function, and low cost, our strategy might provide solutions for treating wastewater containing oil or dye, thus expanding the application range of membrane materials.

中文翻译：

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制备基于埃洛石的 PVDF 膜，用于有效油/水分离和染料去除


由于漏油频繁、含油废水大量排放以及传统分离方法存在诸多缺点，具有选择性超润湿性的材料在油/水分离中的应用备受关注。在此，我们通过在原始商业亲水性聚偏二氟乙烯 （PVDF） 膜上共沉淀盐酸多巴胺和聚乙烯聚胺，并在膜上涂覆埃洛石基水合层，成功制备了双重防御膜。我们的膜在分离水包油乳液方面效率很高（>99.6%），具有出色的回收能力，良好的防污性能（水下油接触角为 156.6 ± 1.9°，油粘附性低），并且耐酸、碱和盐。此外，我们的膜还可以通过简单的过滤去除不同的染料溶液。凭借双重防御设计、在各种环境下优异的水下疏油性能、油水乳化分离性能、染料去除功能、低成本等优点，我们的策略可能为处理含油或染料的废水提供解决方案，从而扩大膜材料的应用范围。