Nie Lina, Goh Kunli, Wang Yu, Lee Jaewoo, Huang Yinjuan, Karahan H Enis, Zhou Kun, Guiver Michael D, Bae Tae-Hyun
School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.
Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore.
Sci Adv. 2020 Apr 24;6(17):eaaz9184. doi: 10.1126/sciadv.aaz9184. eCollection 2020 Apr.
Membranes for organic solvent nanofiltration (OSN) or solvent-resistant nanofiltration (SRNF) offer unprecedented opportunities for highly efficient and cost-competitive solvent recovery in the pharmaceutical industry. Here, we describe small-flake graphene oxide (SFGO) membranes for high-performance OSN applications. Our strategy exploits lateral dimension control to engineer shorter and less tortuous transport pathways for solvent molecules. By using La as a cross-linker and spacer for intercalation, the SFGO membrane selective layer was stabilized, and size-dependent ultrafast selective molecular transport was achieved. The methanol permeance was up to 2.9-fold higher than its large-flake GO (LFGO) counterpart, with high selectivity toward three organic dyes. More importantly, the SFGO-La membrane demonstrated robust stability for at least 24 hours under hydrodynamic stresses that are representative of realistic OSN operating conditions. These desirable attributes stem from the La cross-linking, which forms uniquely strong coordination bonds with oxygen-containing functional groups of SFGO. Other cations were found to be ineffective.
用于有机溶剂纳滤（OSN）或耐溶剂纳滤（SRNF）的膜为制药行业中高效且具有成本竞争力的溶剂回收提供了前所未有的机会。在此，我们描述了用于高性能OSN应用的小片状氧化石墨烯（SFGO）膜。我们的策略利用横向尺寸控制来设计更短且曲折度更小的溶剂分子传输路径。通过使用镧作为交联剂和嵌入间隔物，SFGO膜的选择性层得以稳定，并实现了尺寸依赖性的超快选择性分子传输。甲醇渗透率比其大片状氧化石墨烯（LFGO）对应物高出2.9倍，对三种有机染料具有高选择性。更重要的是，SFGO-La膜在代表实际OSN操作条件的流体动力学应力下表现出至少24小时的强大稳定性。这些理想特性源于镧交联，它与SFGO的含氧官能团形成了独特的强配位键。发现其他阳离子无效。
