Abstract Thin-film nanocomposite (TFN) hollow fibers consisting of unique 3-dimensional (3D) hollow cup-like macrocyclic compounds with different intrinsic size-sieving cavities and functionality have been incorporated into the polyamide layer via interfacial polymerization on the inner surface of polyethersulfone (PES) hollow fiber substrates for boron removal. It is found that the TFN membrane comprising water-soluble sulfocalix [4]arene (SCA4) nanoparticles have the best performance because SCA4 not only possesses a proper pore size of 4.2 A but also forms ionic bonds with the polyamide network. Comparing with the blank thin-film composite (TFC) membrane, the newly developed TFN membrane incorporated with 0.05 wt% SCA4 has 37.5%, 32.1% and 37.4% higher water fluxes at pH equal to 4, 8 and 10, respectively, while their rejections are comparable of about 66.0%, 87.7% and 97.3% at pH = 4, 8 to 10, respectively. Clearly, the unique SCA4 closed-loop structure provides the TFN membrane with additional free volume for water transport without compromising its molecular sieve capability for boron removal. This study may provide a useful strategy to design next-generation nanofiltration membranes using hollow cup-like macrocyclic compounds for water reuse and boron removal.

中文翻译：

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用于除硼的新型分子可调薄膜纳米复合纳滤中空纤维膜的研究

摘要 薄膜纳米复合材料 (TFN) 中空纤维由独特的 3D (3D) 空心杯状大环化合物组成，具有不同的固有尺寸筛孔和功能，已通过聚醚砜内表面的界面聚合结合到聚酰胺层中。 (PES) 中空纤维基材用于去除硼。研究发现，包含水溶性硫杯[4]芳烃（SCA4）纳米颗粒的TFN膜具有最佳性能，因为SCA4不仅具有4.2A的适当孔径，而且还与聚酰胺网络形成离子键。与空白薄膜复合 (TFC) 膜相比，新开发的 TFN 膜掺入了 0.05 wt% SCA4，在 pH 值等于 4、8 和 10 时的水通量分别提高了 37.5%、32.1% 和 37.4%，而在 pH = 4、8 至 10 时，它们的拒绝率分别约为 66.0%、87.7% 和 97.3%。显然，独特的 SCA4 闭环结构为 TFN 膜提供了额外的水传输自由体积，而不会影响其分子筛去除硼的能力。该研究可能为设计使用空心杯状大环化合物用于水再利用和硼去除的下一代纳滤膜提供有用的策略。