Solvent extraction of Sr2+ and Cs+ using protic amide-based ionic liquids
- ORNL
Sixteen protic amide-based ionic liquids (ILs) derived from N,N-dimethylformamide and other protophilic amide derivatives with bis(trifluoromethanesulfonyl)imide or bis(perfluoroethylsulfonyl)imide as conjugated anions were synthesized in a one-pot reaction with very high yields. All sixteen of these protic ionic liquids (PILs) were characterized by NMR spectra, thermogravimetric analysis, and differential scanning calorimetry. These protic amide-based ionic liquids were tested as extraction solvents using dicyclohexano-18-crown-6 (DCH18C6) as an extractant for separation of Sr2+ and Cs+ from aqueous solutions. The extraction efficiencies were studied in comparison with those derived from both imidazolium-based and ammonium-based IL extraction systems. Excellent extraction efficiencies were found for a number of these ILs using DCH18C6 as an extractant. Unlike findings for imidazolium-based and ammonium-based ILs, the observed enhancement trend for the extraction efficiency associated with our amide-based ILs is not directly correlated with the enhanced hydrophilicity of the corresponding cations of the PIL system. The effects on extraction efficiencies of solution acidities, anions, and alkyl chain lengths in the cations of ILs were also investigated and reported.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 990689
- Journal Information:
- Separation Science and Technology, Vol. 45, Issue 12-13; ISSN 0149-6395
- Country of Publication:
- United States
- Language:
- English
Similar Records
Studies on thermal properties of selected aprotic and protic ionic liquids
Unveiling the transport properties of protic ionic liquids: Lithium ion dynamics modulated by the anion fluorine reservoir