| 摘要 |
Solvent extraction system for separating yttrium from mixed rare earth metals. B6A. comprises (a) multistage countercurrent liquid-liquid extraction of the initial solution containing inorganic salts of the metals with a hydrocarbon solution of a branched chain carboxylic acid which is branched on the C atom adjacent the -COOH group the solution also containing yttrium and rare earth metal ions, the solutions being recirculated until a separation is achieved, b) stopping the extraction when the separation is sufficient and emptying one or more stages of the system containing Y ions contaminated with some rare earth metal ions, c) isolating the metal ions and, where necessary, converting to nitrates, d) multistage countercurrent liquid-liquid extraction of the nitrate solution with a solution of the nitrates in tributylphosphate, the solutions being recirculated until a separation is achieved, and e) stopping the extraction when the separation is sufficient and emptying one or more stages of the system containing a solution of suitably pure yttrium. In an alternative method the solvent pairs may be used that form step a) for step d) and that from step d) for step a).
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