Organic phase extraction and rare-earth separation process

Abstract

The invention relates to an organic phase extraction and rare-earth separation process. According to the organic phase extraction and rare-earth separation process, a saponified organic extractant is mixed with water-phase rare-earth solution, rare-earth ions are exchanged and enter an organic phase to complete a rare-earth extraction process, then the organic phase enters a washing section and / or an acid pickling section, the organic phase is washed by acid solution or the rare-earth solution, or rare earth in the organic phase is reversely extracted by inorganic acid to obtain a blank organic phase for a cycle, the blank organic phase is pre-treated before cyclical use, impurities mainly containing uranium and thorium in the blank organic phase are reversely extracted by washing solution in sequence, and the blank organic phase is washed. The rare-earth impurities of uranium and thorium which are difficult to remove are removed through pre-treating the blank organic phase before cycle, and the contents of uranium and thorium in the blank organic phase are reduced to be below the original 10% respectively, so as to improve the extraction effect of the organic phase and guarantee the cycle performance of the organic phase, and then improve yield and product quality.

Description

technical field [0001] The invention belongs to the technical field of rare earth extraction, and in particular relates to a saponified organic phase circulation extraction process for rare earth stock solution. Background technique [0002] Rare earth elements are difficult to separate due to their similar properties. At present, the separation and purification of rare earths generally adopt solvent extraction method. This method is based on the extraction and separation of rare earth elements existing in aqueous solution with an organic solvent immiscible with aqueous solution. A rare earth element with a high separation coefficient or The rare earth element group is preferentially extracted into the organic phase (extractant), and the rare earth element or rare earth element group with a lower separation coefficient is enriched in the water phase, and undergoes multi-stage multi-stage extraction and exchange, thereby realizing the separation of various rare earth elements...

AI Technical Summary

Problems solved by technology

In practice, it is found that the extraction effect of organic extractants will decrease significantly after being recycled for several cycles, which has become a technical problem that plagues those skilled in the art

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