The application and research progress of magnetic resin and its combined processes in the field of water treatment

Magnetic resins, due to their excellent treatment performance, have become important adsorbent materials in the field of water treatment and have attracted widespread attention. This paper systematically summarizes the physicochemical properties and characteristics of the commercialized magnetic resin MIEX®, and provides an overview of its applications in various fields, including drinking water and wastewater treatment. The significant cost-effectiveness advantages of magnetic resins are highlighted. The adsorption mechanisms of magnetic resins are introduced, revealing the interactions between the resins and pollutants, as well as the key factors affecting removal efficiency. The combinations of magnetic resins with other water treatment technologies, including ozonation, coagulation, activated carbon, membrane filtration, and cation exchange resins are analyzed. The advantages and limitations of these combinations are evaluated, emphasizing their potential in improving pollutant removal efficiency. Furthermore, the research and application progress of novel magnetic resins is summarized, and a comparison of the performance of different magnetic adsorbents is presented, along with an analysis of their advantages and disadvantages. The paper points out the research gaps regarding the impact of desorption of inorganic ions on subsequent treatments and the application of magnetic resins as flow electrodes, and proposes future directions, including the development of novel magnetic resins, the application of resins with different exchangeable ions, the preparation of catalysts from used magnetic resins, the selection of resin regeneration liquids, and the development of low-cost combination/coupling processes. With increasingly stringent water quality standards and growing demands for water treatment, magnetic resins and their combination/coupling processes show great potential for future application and development.