Recent advances in polymer membranes employing non-toxic solvents and materials

Polymer membranes have attracted interest in many areas, such as desalination, water treatment, gas separation, and energy storage and generation. Membrane fabrication requires large amounts of solvents for polymer dissolution. These solvents often show toxicity and need to be replaced by greener solvents to avoid adverse effects on human health and increase sustainability of the production processes. The need to use non-toxic compounds is increasing with the strong growth of the global membrane market. This review focuses on green solvents and green materials to prepare polymer-based membranes for the steadily increasing range of applications. Membrane fabrication techniques, choice of emerging green solvents, economic evaluation, and application areas will be comprehensively and critically reviewed. This review provides important selection guidelines for greener solvents for chemists, chemical engineers, and material scientists, focusing on organic chemicals and polymer processing. Furthermore, a simple cost analysis for a typical green solvent is provided, and its impact on the membrane fabrication cost is discussed.