A critical review on solvent extraction of rare earths from aqueous solutions

摘要: Rare earth elements have unique physicochemical properties that make them essential in many high-tech components. Bastnesite (La, Ce)FCO3, monazite, (Ce, La, Y, Th)PO4, and xenotime, YPO4, are the main commercial sources of rare earths. minerals usually beneficiated by flotation or gravity magnetic processes to produce concentrates subsequently leached with aqueous inorganic acids, such as HCl, H2SO4, HNO3. After filtration counter current decantation (CCD), solvent extraction is used separate individual earths mixed solutions compounds. producers follow similar principles schemes when selecting specific routes. The use cation exchangers, solvation extractants, anion for separating has been extensively studied. choice extractants influenced both cost considerations requirements technical performance. Commercially, D2EHPA, HEHEHP, Versatic 10, TBP, Aliquat 336 widely processes. Up hundreds stages mixers settlers may be assembled together achieve necessary separations. This paper reviews chemistry different typical configurations