Water Desalination via Pressure-Driven Distillation with Chlorine-Resistant and Large-Area Polymeric Membranes

Pressure-driven distillation is a separation processin which hydraulicpressure is used to drive water vapor transport across an air-trappingporous hydrophobic membrane. Current development of pressure-drivendistillation is limited by a lack of robust, large-area membranes.Here, we report desalination using pressure-driven vapor transportthrough scalable polymeric polytetrafluorethylene membranes. The membranesshowed pressure-driven water flow with near-complete rejection ofsodium chloride (greater than 99%) under hydraulic pressures of upto 10.3 bar. Membrane structure, surface chemistry, and desalinationperformance were found to be unaffected by doses of sodium hypochloriteup to 3000 ppm h. Flux decline due to biofouling from Pseudomonasaeruginosa bacterium was effectively mitigated using chlorine.Membranes also exhibited high temperature resilience with operationup to 60 & DEG;C. Overall, this work demonstrates the use of large-areapolymeric materials in pressure-driven distillation and highlightskey advantages in chlorine and heat tolerance.