title: Evaluation of solid-supported room-temperature ionic liquids containing crown ethers as media for metal ion separation and preconcentration.
abstract: Extraction chromatographic (EXC) resins incorporating an appropriate crown ether in an oxygenated organic solvent such as 1-octanol are well established as sorbents for the analytical-scale separation and preconcentration of radiostrontium from a variety of sample types. Recent solvent extraction studies employing crown ethers in various 1-alkyl-3-methylimidazolium-based (CnC1im(+)) room-temperature ionic liquids (RTILs) indicate that under certain conditions, distribution ratios (DSr) for strontium far in excess of those observed with conventional organic solvents are observed. To determine if this increase in liquid-liquid extraction efficiency will lead to improved strontium sorbents, several EXC resins and sol-gel glasses incorporating di-tert-butylcyclohexano-18-crown-6 (DtBuCH18C6) in either 1-decyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide (C10C1imTf2N) or the related hydroxyalkyl-functionalized IL 1-(12-hydroxydodecyl)-3-butylimidazolium bis[(trifluoromethyl)sulfonyl]imide (C12OHC4im Tf2N) were prepared and characterized. Unexpectedly the performance of these materials was not uniformly better than that of a conventional EXC resin, an apparent result of the greater viscosity of the ionic liquids and the lower solubility of the crown ether in ILs versus conventional organic solvents.
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210N. Cramer Street, Milwaukee, WI 53211, United States; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, United States.
authors: Cory A
authors: CA
authors: Hawkins
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210N. Cramer Street, Milwaukee, WI 53211, United States.
authors: M A
authors: MA
authors: Momen
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210N. Cramer Street, Milwaukee, WI 53211, United States.
authors: Sarah L
authors: SL
authors: Garvey
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210N. Cramer Street, Milwaukee, WI 53211, United States.
authors: John
authors: J
authors: Kestell
authors: Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, United States.
authors: Michael D
authors: MD
authors: Kaminski
authors: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210N. Cramer Street, Milwaukee, WI 53211, United States; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, United States. Electronic address: dietzm@uwm.edu.
authors: Mark L
authors: ML
authors: Dietz
mesh_terms: D000327:Adsorption; D002845:Chromatography / Q000379:methods; D043844:Crown Ethers / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D059625:Liquid-Liquid Extraction; D012995:Solubility; D013324:Strontium / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity
chemical_list: D043844:Crown Ethers; D052578:Ionic Liquids; D013324:Strontium
keywords: Crown ethers; Extraction chromatography; Ionic liquids; Strontium