A review of the beneficiation of rare earth element bearing minerals

Rare earth elements (REEs) comprise the fifteen elements of the lanthanide series as well as yttrium, and may be found in over 250 different minerals. These elements are required for many different applications such as high-strength permanent magnets, catalysts for petroleum refining, metal and glass additives and phosphors used in electronic displays. The only REE bearing minerals that have been extracted on a commercial scale are bastnäsite, monazite, and xenotime. These minerals may be beneficiated using gravity, magnetic, electrostatic and flotation separation techniques. Increased demand for the different products manufactured from REE has resulted in a constriction of supply from China, which currently produces 97% of the world’s rare earths, via export quotas. Many new rare earth deposits are currently being developed to help meet the demand void created by the Chinese export quotas, however most of these developing deposits include rare earth minerals for which there is limited processing knowledge. This paper examines the separation techniques that are currently employed for rare earth mineral beneficiation and identifies areas in need of further research.

► Review conducted of RE mineral beneficiation using English and Chinese language sources. ► Of the 250 known RE minerals only bastnäsite, monazite and xenotime are extracted commercially. ► Flotation, using fatty acids or hydroxamates, is the primary separation process for RE minerals. ► Currently, optimal beneficiation processes employ flotation, gravity and magnetic separation. ► Research still limited – significant gap in knowledge has been observed.