This technology involves manufacturing a thin-film composite (TFC) membrane for forward osmosis (FO) by creating a porous support through the photocuring of a prepolymer solution—consisting of highly hydrophilic polyethylene glycol diacrylate (PEGDA), a photoinitiator, and a solvent—and subsequently forming a selective layer on top.
Commercial cellulose triacetate (CTA) membranes for forward osmosis suffer from low water permeability and poor pH stability due to their dense, monolithic structure. Polymers like polysulfone, commonly used as supports for TFC membranes, are typically produced via phase inversion, resulting in low porosity, difficult-to-control pore structures, and insufficient hydrophilicity. Methods involving the coating of hydrophilic polymers often lead to pore blockage and increased process complexity, reducing economic viability.
This technology utilizes 250–400 nm UV light to photopolymerize PEGDA, obtaining a hydrophilic porous support through a simple process, followed by the application of a 1 nm to 10 μm thick selective layer via interfacial polymerization, dip coating, or layer-by-layer (LbL) assembly. Crosslinkers or reinforcing agents such as TiO2 or mesoporous SiO2 can be added as needed. Applicable to seawater desalination, wastewater FO processes, pressure-retarded osmosis (PRO) salinity gradient power, and concentration of valuable substances in food and pharmaceuticals, this membrane reduces internal concentration polarization to boost water flux and offers high fouling resistance due to its hydrophilic surface.
This invention was developed with support from the Ministry of Science, ICT and Future Planning for the development of molecular layer-by-layer assembly technology for FO membranes.
N/A
