Review of fluoropolymer-based membranes for membrane distillation applications

Water scarcity is a critical global issue, driven by increasing demand for freshwater due to population growth, industrialization, and climate change. Addressing this challenge requires innovative approaches, with seawater desalination and advanced water treatment technologies playing a crucial role. Seawater desalination has become a vital source of freshwater, particularly in arid and semi-arid regions. Traditional methods such as reverse osmosis (RO) and multi-stage flash (MSF) distillation are widely adopted but suffer from high energy consumption and environmental concerns. Membrane technologies, in particular, offer promising solutions for improving energy efficiency and sustainability in desalination. Conventional membrane technologies such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and RO are integral to modern water treatment. While effective at removing contaminants, these methods still face challenges such as fouling and high operational costs. To address these issues, novel membrane technologies have emerged, with membrane distillation (MD) being a key focus due to its ability to operate at lower temperatures and handle highly saline feedwaters. Fluoropolymers play a pivotal role in the development of novel MD membranes. Materials such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and various copolymers (e.g., FEP, ECTFE) exhibit unique properties such as high hydrophobicity, thermal stability, and chemical resistance that make them ideal for MD. Their hydrophobic nature allows vapor flow while blocking liquid water, which is critical for MD processes. Moreover, fluoropolymers are adaptable to advanced fabrication techniques such as electrospinning and phase inversion, and they can be post-modified to enhance performance, reduce fouling, and increase permeability. These attributes make fluoropolymers essential for developing high-performance MD membranes, enabling efficient and sustainable water treatment. This review highlights recent advancements in MD membranes, focusing on fluoropolymer innovations, fabrication techniques, and their impact on desalination technologies. • Seawater Desalination and Membrane Technology Innovations • Role of Fluoropolymers in Advanced MD Membranes • Enhanced Performance and Sustainability in Water Treatment