Sun Wuyang, Ding Linghui, Xu Peixuan, Zhu Baikang, Ma Ke Cun, Chen Qingguo
Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control, Zhejiang Ocean University, Zhoushan, P. R. China.
National & local Joint Engineering Research Center of Harbor Oil & Gas Storage and Transportation Technology, Zhejiang Ocean University, Zhoushan, P. R. China.
Water Environ Res. 2025 Jan;97(1):e70006. doi: 10.1002/wer.70006.
The discharge of oil-laden wastewater from industrial processes and the frequent occurrence of oil spills pose severe threats to the ecological environment and human health. Membrane materials with special wettability have garnered attention for their ability to achieve efficient oil-water separation by leveraging the differences in wettability at the oil-water interface. These materials are characterized by their simplicity, energy efficiency, environmental friendliness, and reusability. Among them, superhydrophilic-underwater superoleophobic membranes inspired by biomimetic fish scale structures have become a focal point of oil-water separation research due to their ability to repel oil contaminants effectively and maintain self-cleaning properties during the separation process. In this study, a stainless steel microporous two-dimensional metal mesh was employed as the substrate, coated with a carrageenan solution, and gelled in situ using sodium periodate as a crosslinking agent to fabricate a membrane with oil-water separation capabilities. The robust hydrophilicity of the carrageenan hydrogel imparts the coated stainless steel mesh with superhydrophilicity and underwater superoleophobicity (underwater oil contact angle ≥ 158°), along with excellent antifouling properties and recyclability. Experimental results demonstrate that the membrane achieved separation efficiencies of 98.87%, 98.08%, 98.14%, and 97.98% for silicone oil, canola oil, cyclohexane, and liquid paraffin, respectively, with a water flux of 1380.75 L/m·h. Remarkably, the membrane retained its initial separation efficiency even after 20 cycles. Additionally, the hydrogel exhibited exceptional stability under highly alkaline conditions, making it suitable for the treatment of complex oil-contaminated wastewater. PRACTITIONER POINTS: This study extracted a biocompatible and renewable hydrogel from marine red algae for application in oil-water separation. A superhydrophilic/underwater superoleophobic oil-water separation membrane was developed based on biomimetic fish scale structures. The membrane exhibited exceptionally high separation efficiency under pure gravity-driven conditions. The resulting material exhibits excellent oil repellency, self-cleaning capability, and recyclability.
工业生产过程中含油废水的排放以及频繁发生的石油泄漏对生态环境和人类健康构成了严重威胁。具有特殊润湿性的膜材料因其能够利用油水界面润湿性的差异实现高效油水分离而受到关注。这些材料具有操作简单、节能、环保和可重复使用的特点。其中，受仿生鱼鳞结构启发的超亲水-水下超疏油膜由于能够有效排斥油污并在分离过程中保持自清洁性能，已成为油水分离研究的焦点。在本研究中，以不锈钢微孔二维金属网为基底，涂覆角叉菜胶溶液，并使用高碘酸钠作为交联剂进行原位凝胶化，制备了具有油水分离能力的膜。角叉菜胶水凝胶强大的亲水性赋予涂覆的不锈钢网超亲水性和水下超疏油性（水下油接触角≥158°），同时具有优异的抗污染性能和可回收性。实验结果表明，该膜对硅油、菜籽油、环己烷和液体石蜡的分离效率分别达到98.87%、98.08%、98.14%和97.98%，水通量为1380.75 L/m·h。值得注意的是，该膜即使在20次循环后仍保持其初始分离效率。此外，水凝胶在高碱性条件下表现出优异的稳定性，适用于处理复杂的含油废水。从业者要点：本研究从海洋红藻中提取了一种生物相容且可再生的水凝胶用于油水分离。基于仿生鱼鳞结构开发了一种超亲水/水下超疏油的油水分离膜。该膜在纯重力驱动条件下表现出极高的分离效率。所得材料具有优异的拒油性、自清洁能力和可回收性。
