Journal of Solution Chemistry

, Volume 48, Issue 1, pp 15–30 | Cite as

Synergism in the Solvent Extraction of Europium(III) with Thenoyltrifluoroacetone and CMPO in Methylimidazolium Ionic Liquids

  • Maria AtanassovaEmail author
  • Vanya Kurteva


The solvent extraction of Eu(III) from an aqueous chloride phase into hydrophobic ionic liquids (ILs), 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imides ([C1Cnim+][Tf2N], n = 4, 6, 8 and 10), by β-diketone 2-thenoyltrifluoroacetone (HTTA) alone and in combination with N,N-diisobutyl-2-(octylphenylphosphoryl)acetamide (CMPO) was investigated. The interaction between the two extractants (acidic/neutral) in deuterochloroform has been studied by 1H, 13C, 19F and 31P NMR spectra and NOESY experiments. 1H and 19F Q-NMR analytical techniques were also applied for determination of [C1C4im+] and [Tf2N] entities transferred into the aqueous phase. Eu(III) was efficiently extracted by HTTA/[C1Cnim+][Tf2N] and HTTA/CMPO/[C1Cnim+][Tf2N] systems but a relatively small synergism was established. A cation extraction mechanism was proposed via the log–log slope analysis method. The effect of the IL cation alkyl chain length on the extraction process was studied as well.


Synergism Ionic liquids Lanthanoids Thenoyltrifluoroacetone CMPO Q-NMR 



The authors are grateful to FP7-PEOPLE-Marie Curie Actions-IEF for the support of the Project INNOVILLN (622,906: 2014/2015) as well as the Grants 11602/2016 and 11714/2017 from UCTM.

Supplementary material

10953_2019_844_MOESM1_ESM.docx (398 kb)
Supplementary material 1 (DOCX 398 kb)


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Authors and Affiliations

  1. 1.Department of General and Inorganic ChemistryUniversity of Chemical Technology and MetallurgySofiaBulgaria
  2. 2.Institute of Organic Chemistry with Centre of PhytochemistryBulgarian Academy of SciencesSofiaBulgaria

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