Polyimide-based separation membranes for liquid separation: A review on fabrication techniques, applications, and future perspectives

The development of polymeric membranes that are thermally and chemically stable, and can withstand harsh environments such as extreme temperatures, pH levels, oxidants like chlorine, and organic solvents, remains a challenge. To address this issue, high-performance polymers such as polyimides (PIs) can be utilized to create a new generation of membranes for water treatment and desalination. PI membranes exhibit excellent resistance to virtually all chemicals and can be designed to be either hydrophobic or hydrophilic. Additionally, their thermal resistance enables separations to be achieved at high temperatures for extended periods. This review provides a brief introduction to PIs and focuses on the fabrication and design of PI-based membranes for various liquid separation applications, including filtration membranes, membrane distillation, pervaporation, ion exchange, and solvent resistance membranes for future research. Finally, the progress, limitations, and challenges of PI-based membrane preparation and modification are compared to obtain comprehensive information for the development of next-generation membranes with enhanced filtration and separation performance.