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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]

Membrane fouling occurs in all membrane processes. Surface modifications have gained popularity for enhancing membrane antifouling capability via introducing a hydrophilic component or reducing membrane surface roughness. In this work, we proposed to develop a green antimicrobial lysozyme nanofilm on the polyamide membrane surface with remarkable antibacterial and antifouling properties to effectively reduce membrane fouling. The nanofilm is rooted in the molecular assembly of a protein which is an extraction of food and natural products. The nanofilm exhibits the combination of various functions including antimicrobial, antifouling and antibiofilm. This protein-based nanofilm is robustly transferred and self-adhered on the membrane surface by a simple one-step aqueous coating. The modified RO membrane exhibited good performance in bacterial reduction of ~50% in comparison to the control membrane and experienced almost zero loss in water flux and salt rejection under SWRO testing condition. The membrane is further evaluated with real seawater for 14 days and the modified membrane showed its superiority in flux and fouling control which were verified by the confocal laser scanning microscopy (CLSM) and quantified by inductively coupled plasma optical emission spectrometer (ICP-OES). This work demonstrates that the protein-based biomaterials offer a safe and environmentally friendly way of antimicrobials, which can reduce membrane fouling significantly in membrane filtration. Unlabelled Image • A protein-based antimicrobial nanofilm was in-situ fabricated on a commercial SWRO membrane surface. • The modification did not change the SWRO membrane's selectivity and water permeability. • The modified membrane demonstrated ~50% bacterial reduction compared to the control membrane. • The modified membrane had good anti-fouling property applied in SWRO. [ABSTRACT FROM AUTHOR]