Vapor-based interfacial polymerization of polyester TFN membranes with amino acid-functionalized GO interlayers for saline water recovery

The rapid growth of industrial sectors such as textiles, petrochemicals and pharmaceuticals generates large volumes of saline wastewater, presenting a valuable opportunity for resource recovery through water reuse in industrial processes. However, conventional thin film composite (TFC) membranes, which are primarily manufactured using fossil-fuel-derived solvents and monomers, possess a dense structure that limits their suitability for saline water recovery applications. In this study, we developed a more sustainable membrane through solvent-free interfacial polymerization, using glucose as the aqueous-phase monomer to synthesize a polyester selective layer. To further enhance separation performance, graphene oxide (GO) functionalized with amino acids was incorporated as a functional interlayer to fabricate a thin film nanocomposite (TFN) membrane. Compared to the control TFC membrane, the TFN membrane achieved a 51.7% increase in pure water permeance, reaching 42.88 L/m²·h·bar. This enhancement is attributed to the improved water transport pathways and increased hydrophilicity imparted by the functionalized GO interlayer. Although both membranes displayed low NaCl rejection, the TFN membrane demonstrated superior performance in removing contaminants, achieving >99.69% rejection of dyes, oils and antibiotics. It also exhibited excellent salt-to-contaminant selectivity and maintained high stability over prolonged operation, with >99% solute rejection and >90% saline water recovery. Overall, this work presents a sustainable approach to fabricating high-performance, fouling-resistant TFN membrane suitable for the recovery and reuse of saline wastewater across diverse industrial sectors.