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Pressure retarded osmosis (PRO) has been identified as a promising technology to harvest the salinity gradient energy. For practical applications of PRO process, membrane fouling is a challenging issue as it leads to severe decline of PRO performance in terms of water flux and power density. It is imperative to develop anti-fouling membranes for PRO process. The current study demonstrated the unique roles and the great potential of aminosilane in developing anti-fouling thin film composite (TFC) PRO membranes. Experimental results revealed that aminosilane as a grafting agent can modify both the support layer (interior) and the selective layer of PRO membranes with remarkably enhanced hydrophilicity via a very simple grafting procedure. In the grafting, aminosilane was able to minimize the pore-blocking issue with almost no increase in the membrane structural parameter ( S ). Meanwhile, the membrane mechanical strength was well maintained with the grafting due to the capability of aminosilane as a cross-linker. With enhanced hydrophilicity, it was interestingly found that the water permeability ( A ) was doubled, while the salt rejection was maintained nearly unchanged. The combination of these effects brought in remarkably enhanced water flux, power density and anti-fouling property to the resultant membrane. [ABSTRACT FROM AUTHOR]

This study focuses on enhancing the mechanical strength of aquaporin (AQP)-based biomimetic membranes for seawater desalination. AQP incorporated vesicles were embedded into the selective layer of an optimized thin film composite (TFC) membrane. The resultant membrane, denoted as ASW, exhibited a stable water flux around 20 L·m−2·h−1 and 99% NaCl rejection at a constant pressure of 55 bar using 32,000 mg·L−1 NaCl solution as feed in reverse osmosis (RO) measurement. The robustness of the ASW membranes were evaluated. The water flux of ASW membrane was almost 100% enhanced compared with that of AQP-free control TFC membranes. The filtration performance of the ASW membrane was further evaluated by a seven-day desalination test using a real seawater secondary effluent collected from a desalination plant in Singapore as feed. To our best knowledge, our study is the first report on the AQP-incorporated RO membrane applied for seawater desalination. A commercial SW30HR membrane was tested in parallel for comparison. The robust ASW membrane exhibited a nearly 80% higher water flux in comparison to the SW30HR membrane with a comparable overall solute rejection, suggesting the advantage and feasibility of Aquaporin based biomimetic membranes for seawater desalination. • The mechanical strength of aquaporin incorporated polyamide layer was characterized with AFM. • The effects of high pressure compaction and salinity on aquaporin incorporated polyamide layer were investigated. • The aquaporin based biomimetic membranes were optimized for seawater desalination (SWRO) application. • A seven-day SWRO measurement of the ASW was conducted using a real seawater secondary effluent. [ABSTRACT FROM AUTHOR]