Studies for Extraction and Separation of Rare Earth Elements by Adsorption from Wastewater: A Review

Rare earth elements (REEs) are utilized in numerous disciplines, including chemical engineering, the nuclear industry, metallurgy, medicine, electronics, and computer technology. Recycling products containing and extracting them from effluent is necessary to satisfy the rising demand for these elements. Some studies investigate the adsorption of rare earth elements from dilute aqueous solutions to remove them from effluent. Based on the results of this study, it can be concluded that lab tests demonstrate high adsorption capacities, which vary widely depending on the adsorption type and conditions. The Langmuir, Freundlich, and Temkin isotherms usually describe adsorption isotherms. In addition, the finest models for describing adsorption kinetics are pseudo-second-order and pseudo-first-order models. The thermodynamic parameters, such as the changes in free energy, enthalpy, and entropy, provide additional information regarding the energy changes. Additional research is required to develop environmentally friendly adsorbents that can be used to remove REEs from actual mine wastewater.