Extraction and Separation of Rare Earth Elements by Adsorption Approaches: Current Status and Future Trends

Strategic elements, such as rare earth elements, play a critical part in industry, especially in the production of high-tech materials. Major global industries developed a strong dependence on rare earth materials. Every year, innovations appear in sectors such as modern technology, green energy, or communication technologies needing more strategic metals to increase in the investment profitability. One of the effective extraction methods for rare earth metals in low concentrations is the adsorption process. It has a high selectivity and high efficiency reducing the volume of pollutants in the environment. Many adsorbents from simple materials in nature to complex nanocomposite materials have been described in the literature. In this review, the research works with various adsorbent materials have been described for the extraction and separation of rare earth elements from aqueous solutions or wastewater. In addition, the extraction efficiency of the developed adsorbents is discussed. The trend is illustrated in the application of new materials with high adsorption capacity for the production of rare earth elements.