Compared to the traditional nanofiltration (NF) membrane with molecular weight cut-off (MWCO) below 500 Da, an emerging loose NF (LNF) membrane with MWCO of 500∼2000 Da has attracted increasing interests due to its higher selectivity and lower operating pressure, which exhibited distinct advantages in resource recovery from biomass and wastewater. This review summarizes the development of the LNF membranes, focusing on their preparations and applications. Regarding the membrane preparation, phase inversion and interfacial polymerization are the two leading and scalable fabrication methods, and other methods including dip coating, mussel-inspired deposition, self-assembly, grafting polymerization, and nanomaterials assembly/growth are also widely studied at a laboratory scale. As for the application of LNF, the fractionation of saccharides, polyphenols, and pigments for bioresource recovery as well as the separation of dyes and salts for “zero discharge” become research hotspots due to the increasing industrial demand. Besides the existing challenges faced by the applications of LNF, many opportunities to advance the field are also pointed out. This review not only provides a comprehensive overview on the development of the LNF membrane but also offers guidance to improve the membrane separation performance, especially for the resource recovery to minimize environmental pollution.

与分子量截断（MWCO）低于500 Da的传统纳滤（NF）膜相比，新兴的MWCO为500〜2000 Da的疏松NF（LNF）膜因其较高的选择性和较低的操作压力而引起了越来越多的关注在从生物质和废水中回收资源方面显示出明显的优势。这篇综述总结了LNF膜的发展，重点是其制备和应用。关于膜的制备，相转化和界面聚合是两种领先且可扩展的制造方法，并且在实验室中还广泛研究了其他方法，包括浸涂，贻贝启发式沉积，自组装，接枝聚合以及纳米材料的组装/生长。规模。至于LNF的应用，糖分馏，由于工业需求的增长，多酚，用于生物资源回收的颜料以及用于“零排放”的染料和盐的分离成为研究热点。除了LNF的应用面临的现有挑战外，还指出了推进该领域的许多机会。这篇综述不仅对LNF膜的发展提供了全面的概述，而且还为改善膜分离性能提供了指导，特别是对于资源回收以最大程度地减少环境污染。