Rare earth element reduction to metals

Abstract

The reduction to metal of rare earth elements is a complex, energy-intensive, and environmentally damaging process currently undertaken by molten salt electrolysis for the light rare earth elements (lanthanum (La) to neodymium (Nd)) and by metallothermic reduction for heavier rare earth elements ((samarium (Sm) to lutetium (Lu), yttrium (Y), and scandium (Sc)). The primary metals used as reductants in metallothermic reduction processes are calcium (Ca) and La. New approaches such as electrolysis in ionic liquid medium, the FFC-Cambridge, Fueled Anode Electrolysis, and Carboxylate Reduction processes are set to disrupt the current industrial practices. Their development is a sustainability imperative as they promise to offer a significant reduction in environmental impact and in energy usage.