Engineering nanocomposite polymeric membranes for sustainable water treatment

Rising water pollution, driven by industrialization, urbanization, and agricultural activities, has intensified the demand for efficient and sustainable water treatment technologies. Pressure-driven membrane processes have emerged as promising solutions owing to their high separation efficiency and environmentally friendly operation. This review presents the fundamentals of membrane technology, transport mechanisms, and recent advances in membrane fabrication, including thin-film composite (TFC) and thin-film nanocomposite (TFN) membranes, with particular emphasis on polymeric nanofiltration membranes. It critically discusses the key factors governing membrane performance, including fouling, biofouling, antibacterial and antifouling membrane development, charge-driven separation mechanisms, and the role of nanomaterials in enhancing permeability, selectivity, and membrane stability. The review also examines the practical challenges associated with membrane durability, nanoparticle leaching, scalability, and the economic feasibility of advanced membrane technologies. Finally, it identifies critical research priorities for developing robust, cost-effective, and scalable polymeric membranes for sustainable water purification and wastewater treatment.