Adsorption of heavy metal ions in water by surface functionalized magnetic composites: a review

Abstract

Water pollution caused by toxic heavy metal ions and their by-products can effectively be removed by the adsorption method, but traditional adsorbents generally have problems, such as inconvenient adsorbent recovery, low adsorption capacity, poor selective adsorption, and secondary treatment. Therefore, the development of adsorbents with easy recovery, high adsorption capacity, strong selectivity, which are safe and economical has always been a research hotspot. Nano-magnetic hybrid materials are an important new type of aqueous heavy metal ion adsorbents because their unique nano and magnetic properties and abundant active functional groups enable them to integrate the above-mentioned excellent properties. This review systematically summarizes the application of magnetic composite adsorbents for the removal of heavy metal ions in water and focuses on the surface functionalization of magnetic materials. The goal of this review is to provide the latest research progress, current problems, and future prospects in the removal of heavy metal ions from water by organic small molecule materials, polymeric materials and inorganic materials modified magnetic adsorption materials.