The synergistic extraction of rare earths (REs) from chloride media by a mixture of two extractants 2-ethylhexylaminomethyl phosphonic acid mono-2-ethylhexyl ester (HEHAMP, HA) and sec-octylphenoxy acetic acid (CA12, HB) was investigated. A remarkable positive synergistic effect was observed at the molar ratio of HEHAMP to CA12 being of 2:3. The extraction of REs was found to be a cation exchange process and the extracted species of Yb³⁺ was determined as YbCl₂HAB. The separation factors (SF) of adjacent heavy REs, i.e. SF_Yb/Tm and SF_Lu/Yb, for the mixtures were 2.50 and 1.63, which were much higher than those of the sole HEHAMP and the sole CA12 system. In additional, the values of SF_Yb/Y and SF_Lu/Y were 7.17 and 11.14, respectively, which were higher than those of other reported synergistic systems and those of the sole HEHAEP or CA12 system, suggesting that the mixture of HEHAMP and CA12 is a potential synergistic extraction system for the separation of heavy REs and/or Y(III) from other heavy REs. A cascade extraction process for the separation of Y(III) from yttrium-enriched REs feed using the synergistic extraction system was developed, which are superior to sole CA12 system. The Y₂O₃ product with a purity of 99.4% was obtained by 8 extraction stages and 5 scrubbing stages.

研究了两种萃取剂 2-乙基己基氨基甲基膦酸单-2-乙基己酯 (HEHAMP, HA) 和仲辛基苯氧基乙酸 (CA12, HB) 的混合物从氯化物介质中协同萃取稀土 (REs)。在 HEHAMP 与 CA12 的摩尔比为 2:3 时观察到显着的正协同效应。发现稀土元素的提取是一个阳离子交换过程，提取的 Yb ³⁺物质被确定为 YbCl ₂ HAB。相邻重稀土的分离因子（SF），即SF _Yb/Tm和SF _Lu/Yb, 因为混合物为 2.50 和 1.63, 远高于唯一的 HEHAMP 和唯一的 CA12 系统。此外，SF _Yb/Y和SF _Lu/Y的值分别为 7.17 和 11.14，高于其他报道的协同系统和单独的 HEHAEP 或 CA12 系统，表明 HEHAMP 和 CA12 的混合物是一种潜在的协同萃取系统，用于将重稀土和/或 Y(III) 从其他重稀土中分离出来。开发了一种使用协同萃取系统从富钇稀土原料中分离 Y(III) 的级联萃取工艺，该工艺优于单独的 CA12 系统。Y ₂ O ₃经8个萃取阶段和5个洗涤阶段获得纯度为99.4%的产品。