Development of new oil-soluble complexing agents for separation of rare earth metals utilizing interface

近年来，随着新型先进材料的开发，稀土金属的高效分离提纯得到了广泛的研究。利用超纯稀土金属获得了独特的电学、光学和磁学性质。然而，为了制备高纯度的产品，需要经过大量的阶段，因为稀土元素中相邻元素的化学性质和物理性质非常相似。因此，稀土金属具有相互分离困难的固有缺点。本研究开发了一种新的油溶络合剂，它是多氨基羧酸烷基衍生物，具有与表面活性剂类似的界面活性。采用中空纤维膜萃取器，研究了新型萃取剂对稀土金属S的分离效果。(1)通过加入新型络合剂，明确了萃取剂的萃取机理。实验结果可以用伴随界面反应的扩散模型来解释。EDTA-二烯基衍生物对稀土金属的分离效果最佳。其中，新试剂对重稀土金属中Y的分离效果较好。(3)利用络合剂与稀土金属离子在油水界面相互作用的差异，可以在非平衡状态下提高选择性。油水界面对于溶剂萃取法分离稀土金属是非常有用的。

Recently, efficient separation and purification of rare earth metals have been studied intensively in connection with the development of new advanced materials. Unique electronic optical and magnetic properties are obtained by utilizing ultra-purified rare earth metals. However, for preparation of high-purity produces, a large number of stages are needed because the chemical and physical properties of adjacent elements among the lanthanoids are very similar. Rare earth metals have thus the inherent disadvantage that their mutual separation is very difficult.In this study, new oil-soluble complexing agents, which are polyaminocarboxylic acid alkylderivatives and have interfacial activity like that of surfactants have been developed. Separation of rare earth metal s utilizing their new agents were investigated using a hollow-fiber membrane extractor. (1) The extraction mechanism was clarified under the addition of new complexing agents. The experimental results could be explained by a diffusion model accompanied by an interfacial reaction. An EDTA-dioleylderivative gives the best result for the separation of rare earth metals. Among them, the new agent was much effective for separation of yttrium from heavier rare earth metals. (3) The selectivity in this study can be enhanced in a nonequilibrium state by utilizing the difference in interaction between the complexing agent and rare earth metal ions at the oil-water interface. The oil-water interface is very useful for separation of rare earth metals with solvent extraction.