High-Performance PET-TM/PTFE-like Composite Membranes for Efficient Salt Rejection via Air Gap Membrane Distillation

The global water scarcity crisis requires urgent action to improve wastewater treatment and develop sustainable water resources. This study focuses on producing Thin Film Composite (TFC) membranes based on polyethylene terephthalate track membranes (PET-TM) coated with polytetrafluorethylene-like material (PTFE), named PET-TM/PTFE-like, designed to purify saline water using Air Gap Membrane Distillation (AGMD) technique. The research emphasizes the optimization of these membranes' chemical composition and surface characteristics by plasma that enhances their hydrophobicity and overall operational efficiency. A systematic investigation was conducted to clarify the relationship between water flux and salt rejection, enabling the customization of membrane properties for better performance. It was shown that salt rejection exceeding 99% is obtained for all the investigated PET-TM/PTFE-like membranes, with values up to 99.63% for the PET-TM(250 nm)/PTFE-like(200 nm) system and condensate flows as high as 1325 g/m²h for the PET-TM(450 nm)/PTFE-like(200 nm) system. This comprehensive analysis identified the most effective TFC configurations for AGMD applications, providing a promising pathway to advance desalination techniques and wastewater treatment solutions.