Application of resins with functional groups in the separation of metal ions/species – a review

This article presents a comprehensive review of polymeric resins used for metal separation in hydrometallurgy and water/wastewater treatments. The adsorption selectivity of a resin depends on the characteristics of the functional group and solution pH. The resins are reviewed and categorized with respect to the principal acting atoms in functional groups (i.e., nitrogen, sulfur, phosphorous, oxygen) and ion-exchange properties. General selectivity trends, metal ion preferences, and applications reported in the scientific literature are summarized for each functional group. This review is intended as a reference for the selection of ion-exchange resins for metal separation and recovery. The selection criteria also depend on the type of process and metal ion concentration.