Abstract In this study, the synergistic solvent extraction of lanthanide(III) with mixtures of di-(2-ethylhexyl)phosphoric acid (D2EHPA, H2A2) and monoisodecyl phosphoric acid (MIDPA, H2B2) in phosphonium-based ionic liquid was investigated from amide acid medium. The method of slope analysis was used for the determination of the extraction reaction. In the case of D2EHPA or MIDPA single extractant system, Ln(III) (Ln = Pr and Nd) was extracted as [LnA3･HA] or [LnB3･HB], respectively. Tb(III) or Dy(III) were extracted as [TbH2A2B2(NTf2)] or [DyH2A2B2(NTf2)] instead of [TbA3･HA(NTf2)] or [DyA3･HA(NTf2)] for D2EHPA and MIDPA synergistic system. According to the equilibrium constants (KA, KB and KAB) and the formation constants (β1, β1 and β3), it was found that the extracted complex [TbHA2B2] or [DyHA2B2] was more stable than [LnA3･HA] or [LnB3･HB] due to the synergistic effect of D2EHPA and MIDPA. The thermodynamic functions (ΔH, ΔG, and ΔS) were estimated from the temperature dependence of the synergistic extraction system. The result indicated that the synergistic extraction reaction was endothermically driven for this extraction system. Furthermore, the synergistic extraction effects were investigated to study the possibility of separating Dy(III) from Pr(III) and Nd(III) according to their separation factors.

中文翻译：

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鏻基离子液体中镧系元素离子与 D2EHPA 和 MIDPA 混合物的协同溶剂萃取

摘要 本研究从酰胺基离子液体中，研究了二(2-乙基己基)磷酸 (D2EHPA, H2A2) 和单异癸基磷酸 (MIDPA, H2B2) 混合物对镧系元素 (III) 的协同溶剂萃取。酸性介质。采用斜率分析法测定萃取反应。在 D2EHPA 或 MIDPA 单一萃取剂系统的情况下，Ln(III)（Ln = Pr 和 Nd）分别被萃取为 [LnA3･HA] 或 [LnB3･HB]。对于 D2EHPA 和 MIDPA 协同系统，Tb(III) 或 Dy(III) 被提取为 [TbH2A2B2(NTf2)] 或 [DyH2A2B2(NTf2)] 而不是 [TbA3･HA(NTf2)] 或 [DyA3･HA(NTf2)] . 根据平衡常数（KA、KB 和 KAB）和形成常数（β1、β1 和 β3），由于D2EHPA和MIDPA的协同作用，发现提取的复合物[TbHA2B2]或[DyHA2B2]比[LnA3･HA]或[LnB3･HB]更稳定。热力学函数（ΔH、ΔG 和 ΔS）根据协同提取系统的温度依赖性进行估计。结果表明，该萃取系统的协同萃取反应是吸热驱动的。此外，研究了协同萃取效果，以研究根据分离因子从 Pr(III) 和 Nd(III) 中分离 Dy(III) 的可能性。结果表明，该萃取系统的协同萃取反应是吸热驱动的。此外，研究了协同萃取效果，以研究根据分离因子从 Pr(III) 和 Nd(III) 中分离 Dy(III) 的可能性。结果表明，该萃取系统的协同萃取反应是吸热驱动的。此外，研究了协同萃取效果，以研究根据分离因子从 Pr(III) 和 Nd(III) 中分离 Dy(III) 的可能性。