为研究特殊润湿性网膜材料的油水分离特性，通过原位置换和氧化修饰方法，以铜网为基底分别制备Ag和Cu（OH）2微纳米结构的超亲水/水下超疏油网膜。实验对比分析两种网膜油水分离效率、膜通量和稳定性等指标，着重研究微观结构、表面润湿性、入侵压力及介质酸碱性等因素对网膜分离性能的影响。结果表明：两种网膜对柴油、汽油等单油相和多组分混合油相的油水混合物的分离效率均达到99%以上。由于两种网膜的微观结构不同，Ag微纳米结构网膜分离效率略优于Cu（OH）2结构网膜，但Cu（OH）2微纳米结构网膜能够承受的入侵压力更大，且其膜通量更优。两种网膜都具有较优异的耐强碱和非氧化性酸性能。此外，两种网膜在清洗后能重复使用10次以上而效率没有明显降低，并且长期放置后两种网膜分离效率没有明显的降低。总之，这两种网膜无论是在分离效率、介质适应性，还是在重复性、耐久性等方面都具有各自明显优势，应用前景广阔。
In order to study the oil-water separation ability of meshes with special wettability, two copper-based superhydrophilic/underwater-superoleophobic meshes with micro-nano structures of Ag and Cu(OH)2 were prepared by in situ displacement and oxidative modification methods. The effects of microstructure, surface wettability, permeation pressure, and the pH value on the separation performance of meshes were experimentally studied. The results show that the efficiencies of the two meshes for separating oil-water mixtures with single oil (e.g., diesel or gasoline) and multi-oil (e.g., the mixture of diesel and gasoline) both reached more than 99%. Owning to the difference in microstructures, the separation efficiency of the mesh with Ag micro-nano structure was slightly higher than that of the Cu(OH)2 mesh. However, the mesh with Cu(OH)2 micro-nano structure withstood a higher permeation pressure and had a greater liquid flux. Moreover, both the meshes were excellent in acid and alkali resistance. They can be reused for more than 10 times after washing without significant efficiency reducing, and there was no obvious degeneration arising after long-term placement. In short, these two types of meshes showed distinct advantages in separation efficiency, medium adaptability, repeatability, and durability for oil-water separation, and they would have broad application prospects.
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