Towards cleaner production of rare earth elements from bastnaesite in China

Rare earth elements (REEs) play a critical role in numerous high-tech applications owing to their unique magnetic, optical, and electrical properties. China is widely recognized by its abundant rare earth resources with the annual output of 100,000-150,000 tonnes, which accounts for over 90% of the world's total production. Bastnaesite is one of the four rare earth minerals in China. With the rapid development of rare earth industry, resources and environmental issues have attracted more and more public attention around the world. The Chinese government, together with the Chinese researchers, have been devoted to establish a high standard by proactively addressing resources and environmental issues. This review gives an overview of the recent progresses in the environmentally friendly rare earth separation and industrial application of bastnaesite in China, including oxidation roasting-acid leaching process, sulfuric acid bake-water leaching process, caustic soda decomposition process, chlorination process, NH4Cl roasting technique, hyperlink extraction process, equilibrium acidity controlling technique, and some other improved processes. These progresses have exerted important impacts on the wolrd's rare earth industry and futher pointed out the future directions for the technical development of the rare earth industry in China. Moreover, the recent policies on the cleaner production of rare earth industry issued by the Chinese government have been briefly discussed, which provides sufficient policy support for the generalization and application of the advanced cleaner production technologies in the rare earth industry.