Ionic liquid-based extraction of metal ions via polymer inclusion membranes: a critical review

Polymer Inclusion Membranes (PIMs) have significantly advanced the field of membrane-based separation technologies introducing an innovative method for the selective transport and extraction of metal ions. The incorporation of ionic liquids (ILs) into PIMs leverages the exceptional characteristics of ILs to boost both selectivity and efficiency in the separation of metal ions. This synergy advances metal separation processes towards greener and more sophisticated solutions perfectly aligning with green chemistry and environmental sustainability. This review presents an overview of current knowledge on PIMs including the distinct roles of their different components. It critically assesses the different strategies essential for achieving optimal membrane performance and ensuring stability and selectivity of PIMs. Future research directions are discussed particularly focusing on the understanding of transport dynamics within PIMs and refining membrane compositions to reduce the risk of carrier leakage. These investigations promise to enhance the efficiency and environmental friendliness of metal ion separation propelling the field towards more effective and sustainable practices. This review can serve as a roadmap for ongoing research, promoting the advancement of IL-based extraction of metal ions via PIMs for sustainable and efficient metal separation processes.