Current and Alternative Routes in the Production of Rare Earth Elements

Rare Earth Elements (REE) are essential in the day to day life both in developed and developing countries worldwide. Due to their catalytic, magnetic, electrical, chemical, heat resistance, and optical properties, they are used in a wide range of high-tech, high value-added, and fast-growing sectors. The current state-of-the-art processes for REE extraction follows complicated, energy and resource intensive technologies, including a beneficiation stage for the production of a RE-rich concentrate, leaching/purification/separation into individual high purity RE solutions, precipitation as individual RE compounds, and finally production of RE metals or alloys through metallothermic reduction or fused-salt electrowinning. Currently, China is the main REE market player, dominating production, demand, and exports. Novel, cost-effective, and resource-efficient REE extraction processes are currently under development tailored specifically for European REE primary and secondary deposits and for European health, safety, and environmental standards, under the EURARE project. This paper analyses the currently used processing technologies for REE production, identifies problems and technical challenges associated with them, and examines the prospects of establishing novel technologies for an efficient and economically viable REE production from European REE deposits. The results are presented on a promising new technology for extracting REE from secondary resources using ionic liquids. REE extraction yield of 60–80% with respective Fe extraction less than 3% has been already achieved.