Institut Européen des Membranes, Adaptive Supramolecular Nanosystems Group, University of Montpellier, École Nationale Supérieure de Chimie de Montpellier, CNRS, F-34095 Montpellier, France.
Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, 10129 Torino, Italy.
Proc Natl Acad Sci U S A. 2021 Sep 14;118(37). doi: 10.1073/pnas.2022200118.
Membrane-based technologies have a tremendous role in water purification and desalination. Inspired by biological proteins, artificial water channels (AWCs) have been proposed to overcome the permeability/selectivity trade-off of desalination processes. Promising strategies exploiting the AWC with angstrom-scale selectivity have revealed their impressive performances when embedded in bilayer membranes. Herein, we demonstrate that self-assembled imidazole-quartet (I-quartet) AWCs are macroscopically incorporated within industrially relevant reverse osmosis membranes. In particular, we explore the best combination between I-quartet AWC and m-phenylenediamine (MPD) monomer to achieve a seamless incorporation of AWC in a defect-free polyamide membrane. The performance of the membranes is evaluated by cross-flow filtration under real reverse osmosis conditions (15 to 20 bar of applied pressure) by filtration of brackish feed streams. The optimized bioinspired membranes achieve an unprecedented improvement, resulting in more than twice (up to 6.9 L⋅m⋅h⋅bar) water permeance of analogous commercial membranes, while maintaining excellent NaCl rejection (>99.5%). They show also excellent performance in the purification of low-salinity water under low-pressure conditions (6 bar of applied pressure) with fluxes up to 35 L⋅m⋅h and 97.5 to 99.3% observed rejection.
基于膜的技术在水净化和海水淡化方面发挥着巨大的作用。受生物蛋白质的启发，已经提出了人工水通道 (AWC) 来克服海水淡化过程中的渗透性/选择性权衡。利用具有埃级选择性的 AWC 的有前途的策略在双层膜中显示出了令人印象深刻的性能。在此，我们证明了自组装的咪唑-四合体 (I-四合体) AWC 可以在工业相关的反渗透膜中宏观结合。特别是，我们探索了 I-四合体 AWC 和间苯二胺 (MPD) 单体之间的最佳组合，以实现 AWC 在无缺陷聚酰胺膜中的无缝结合。通过在实际反渗透条件下（施加压力为 15 至 20 巴）进行的错流过滤，通过过滤咸水进料流来评估膜的性能。优化后的仿生膜实现了前所未有的改进，使类似的商业膜的水透过率提高了两倍以上（高达 6.9 L⋅m⋅h⋅bar），同时保持了优异的 NaCl 截留率（>99.5%）。它们在低压条件（施加压力为 6 巴）下对低盐度水的净化也表现出出色的性能，通量高达 35 L⋅m⋅h，观察到的截留率为 97.5%至 99.3%。
