Shi Yongxuan, Mai Zhaohuan, Guan Kecheng, Li Bowen, Shen Qin, Song Qiangqiang, Fu Wenming, Xiang Shang, Takagi Ryosuke, Matsuyama Hideto
Research Center for Membrane and Film Technology, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan; Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan.
Research Center for Membrane and Film Technology, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan.
Water Res. 2025 Apr 15;274:123063. doi: 10.1016/j.watres.2024.123063. Epub 2024 Dec 27.
Nanofiltration (NF) offers a scalable and energy-efficient method for lithium extraction from salt lakes. However, the selective separation of lithium from magnesium, particularly in brines with high magnesium concentrations, remains a significant challenge due to the close similarity in their hydrated ionic radii. The limited Li/Mgselectivity of current NF membranes is primarily attributed to insufficient control over pore size and surface charge. In this study, we report the development of an interlayered thin-film composite (iTFC) membrane incorporating functionalized sulfonated carrageenan to regulate the interfacial polymerization process. This integrated interlayer plays a crucial role in controlling the diffusion and spatial distribution of amine monomers, leading to the formation of dense, nano-striped polyamide networks. These structural improvements including refined pore size and reduced negative charge significantly enhanced Li/Mgselectivity (133.5) and increased permeance by 2.5 times compared to conventional TFC membranes. Additionally, the nano-striped structure optimized the membrane filtration area while minimizing ion transport resistance, effectively overcoming the traditional trade-off between ion selectivity and permeability. This study highlights the potential of iTFC membranes for achieving both high lithium purity and recovery, offering a promising avenue for large-scale lithium extraction from brines.
纳滤（NF）为从盐湖中提取锂提供了一种可扩展且节能的方法。然而，由于锂和镁的水合离子半径非常相似，从镁中选择性分离锂，尤其是在高镁浓度的卤水中，仍然是一项重大挑战。当前纳滤膜的锂/镁选择性有限，主要归因于对孔径和表面电荷的控制不足。在本研究中，我们报告了一种层间薄膜复合（iTFC）膜的开发，该膜结合了功能化的磺化角叉菜胶以调节界面聚合过程。这种集成的中间层在控制胺单体的扩散和空间分布方面起着关键作用，导致形成致密的、纳米条纹状的聚酰胺网络。这些结构改进包括细化孔径和减少负电荷，与传统的TFC膜相比，显著提高了锂/镁选择性（133.5），并使渗透率提高了2.5倍。此外，纳米条纹结构优化了膜过滤面积，同时最小化了离子传输阻力，有效克服了离子选择性和渗透性之间的传统权衡。这项研究突出了iTFC膜在实现高锂纯度和回收率方面的潜力，为从卤水中大规模提取锂提供了一条有前景的途径。
