Abstract Oil wastewater discharge, from both domestic and industrial sources, has caused serious environmental problems. Separation of stabilized oil-water emulsions and anti-fouling of membranes remain substantial global challenges. In this work, we fabricated a reversible superwetting sodium bis(2-ethylhexyl) sulfosuccinate-doped polypyrrole (PPy-AOT) membrane for separation of oil-water emulsions and alleviation of membrane fouling by self-cleaning. The PPy-AOT membrane exhibited super-hydrophobicity for water-removal and super-hydrophilicity for oil-removal in oxidation and reduction states, respectively. Results showed that the separation efficiency of the PPy-AOT membrane under oxidation and reduction states exceeded 80%. Moreover, the reduced PPy-AOT membrane with a super-hydrophilic surface showed underwater anti-fouling properties for viscous oils. Simultaneously, the membrane displayed outstanding acid resistance and salt tolerance. Based on density functional theory calculations, the reversible wettability switching of the PPy-AOT membrane was due to the reorientation of AOT anions during the redox process. Thus, the advantageous membrane properties, including reversible superwetting, high separation efficiency, and corrosion protection, show great potential for separation of oil wastewater.

中文翻译：

---

用于油水分离和自清洁的导电聚合物膜的可逆超润湿性转换

摘要 生活和工业来源的石油废水排放已造成严重的环境问题。稳定的油水乳液的分离和膜的防污仍然是重大的全球挑战。在这项工作中，我们制造了一种可逆的超润湿双（2-乙基己基）磺基琥珀酸钠掺杂聚吡咯（PPy-AOT）膜，用于分离油水乳液和通过自清洁减轻膜污染。PPy-AOT膜分别在氧化态和还原态表现出超疏水性去水和超亲水性去油。结果表明，PPy-AOT膜在氧化和还原状态下的分离效率超过80%。而且，具有超亲水表面的还原 PPy-AOT 膜显示出对粘性油的水下防污性能。同时，该膜表现出优异的耐酸性和耐盐性。根据密度泛函理论计算，PPy-AOT 膜的可逆润湿性转换是由于氧化还原过程中 AOT 阴离子的重新定向。因此，有利的膜特性，包括可逆的超润湿、高分离效率和腐蚀保护，显示出分离含油废水的巨大潜力。