METHOD FOR EXTRACTING AND SEPARATING RARE EARTH ELEMENTS

文件类型：PDF文档
文件大小：54K
PROBLEM TO BE SOLVED : To provide a method for extracting and separating rare earth elements which can satisfactory extract and separate adjacent rare earth elements such as neodymium/praseodymium. SOLUTION : An organic phase with diglycol amide acid as an extract and low-polar alcohol as a solvent and a water phase composed of an aqueous solution comprising two or more of rare earth elements are contacted under an acid condition at the pH of ≤3, and solvent extraction is performed using a countercurrent multistage mixer-settler. A rare earth element solution 1, an organic phase 2 and an alkali aqueous solution 3 are introduced from respective pipings into an extraction part A, and acid aqueous solutions 4, 6 are introduced from the respective pipings into a scrub part B and a back-extraction part C. A water phase 5 comprising the rare earth element(s) not extracted into the organic phase and remaining and an aqueous solution 7 into which the rare earth element(s) extracted into the organic phase is back-extracted are recovered. COPYRIGHT : (C)2011, JPO&INPIT