Environmental Analysis and Prospect of Rare Earth Recovery Technology from Electronic Waste

Rare earth elements (REEs) are essential resources for high-tech industries including semiconductors, batteries, electric vehicles, and wind power generation; however, the current global supply chain is overwhelmingly concentrated in specific countries. As environmental pollution from mining and refining processes and geopolitical risks continue to intensify, the importance of recycling technologies that utilize electronic waste (e-waste) as an ‘urban mine’ is rapidly increasing. Against this background, this study aims to comprehensively compare pyrometallurgical, hydrometallurgical, and next-generation eco-friendly recovery technologies, while presenting technical and economic challenges and future development strategies. Electronic waste contains high concentrations of REEs, offering greater recovery potential than natural ores. Analysis revealed that existing pyrometallurgical and hydrometallurgical processes, despite their high recovery rates and efficiency, exhibit clear environmental limitations including massive energy consumption and wastewater generation. Next-generation technologies — including bioleaching, ionic liquids, and deep eutectic solvents (DES) — were found to have the potential to substantially reduce the environmental burden by eliminating hazardous chemicals and enhancing selective recovery performance. Iodide-iodine and thiourea-based leaching systems are also attracting attention as subjects for future research. In particular, life cycle assessment (LCA) results indicated that bioleaching showed lower values in certain environmental impact categories compared to conventional chemical leaching; however, these results may vary depending on feedstock characteristics, functional units, and system boundaries, and caution is advised against generalization. The EU has set a target of 25% domestic recycling of critical raw materials by 2030 through the Critical Raw Materials Act (CRMA), and the U.S. Department of Energy (DOE) is expanding support for e-waste-based REE recovery and refining demonstrations. Korea likewise needs to consider developing e-waste-based REE recovery technologies and establishing demand-linked supply chains, building on existing rare metal development strategies. In summary, bioleaching and low-hazard solvent-based technologies are assessed as promising alternatives for next-generation eco-friendly REE recovery, and further efforts toward demonstration-scale expansion, downstream refining advancement, and techno-economic validation are needed. Based on the collected data, this study examines technical and policy challenges and aims to provide foundational data for future policy improvements and research directions.