Fabrication and modification of nanofiltration membranes for efficient dye/salt separation towards sustainable water and resource recovery: A review

Abstract The selective separation of dyes and salts from textile wastewater is critical for both environmental protection and resource recovery, with nanofiltration (NF) emerging as a key technology for this purpose. This paper provides a systematic review of recent progress in the fabrication and functionalization of high‐performance NF membranes. Key fabrication and modification techniques are discussed, including phase inversion, interfacial polymerization, layer‐by‐layer self‐assembly, and various surface modification strategies. The review then delves into advanced functionalizations aimed at enhancing specific properties, such as hydrophilicity, chlorine resistance, antibacterial activity, and the development of electro‐responsive membranes for on‐demand separation. Critically, this review also addresses the practical challenges, techno‐economics, and sustainability considerations (including membrane regeneration) that are vital for industrial application. Overall, this work highlights the evolution of NF membrane technology toward higher efficiency and multifunctionality, providing a crucial reference for the future development of membranes for wastewater treatment and resource recovery.