First evidence of metal transfer into hydrophobic deep eutectic and low-transition-temperature mixtures: indium extraction from hydrochloric and oxalic acids

International audienceThis is the first report on metallic species transfer from aqueous hydrochloric and oxalic acid media into hydrophobic deep eutectic and low-transition-temperature mixtures composed of quaternary ammonium salts or menthol and carboxylic acids

Synergistic extraction of uranium(VI) with TODGA and hydrophobic ionic liquid mixtures into molecular diluent

International audienceThe extraction of uranium(VI) from aqueous nitric acid solutions with a neutral extractant, N,N,N 0 ,N 0-tetra (n-octyl)diglycolamide (TODGA), and with the mixtures of TODGA and a hydrophobic ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C 4 mim][Tf 2 N]), into a molecular diluent, 1,2-dichloroethane, has been systematically investigated. The extraction efficiency of U(VI) ions was greatly enhanced by addition of a small amount of ionic liquid to an organic phase containing TODGA. The synergistic effect comes from the higher hydrophobicity of U(VI) extracted species formed by TODGA and weakly coordinating Tf 2 N À anions as compared to those formed by TODGA and NO 3 À anions as counterions in the conventional extraction system. Based on our experimental results, we concluded that the partition of Tf 2 N À anions between the two liquid phases is the dominant factor governing the extractability of uranium(VI) with the mixture of TODGA and ionic liquid as extractant. We showed that the extraction of U(VI) from aqueous nitric acid solutions both by TODGA alone and its mixtures with [C 4 mim][Tf 2 N] into 1,2-dichloroethane can be quantitatively described on the basis of the solvation extraction mechanism. However, in the extraction system with added hydrophobic ionic liquid, the partition of Tf 2 N À anions between the two immiscible phases and the interaction between bis(trifluorome thylsulfonyl)imide acid, HTf 2 N, and TODGA molecules in the organic phase should be taken into account

Characterization and application of alkanethiolate self-assembled monolayers on Au-coated chips for Ir(IV) and Rh(III) sorption

International audienceAu-coated Si alpha-particle detectors have been widely used during the chemical characterization of superheavy elements that have been an area of great interest to scientists for decades. Further experiments are aimed at the functionalization of this type of detector to study the chemical properties of meitnerium. It is expected to be a member of the group 9 elements of the periodic table, and its chemical properties have not been studied before. In this study, self-assembled monolayers (SAMs) of 1-(11-mercaptoundecyl)imidazole (Im-C11-SH) and 12-mercaptododecanoic acid (MDDA) on 1 x 1 cm2 Au-coated Si and glass chips were prepared and characterized using several analytical and optical techniques: atomic force microscopy (AFM), nanoprojectile secondary ion mass spectrometry (NP-SIMS), X-ray photoelectron spectroscopy (XPS), ellipsometry, and instrumental neutron activation analysis (INAA). The coverage of Au-coated Si chips with Im-C11-SH SAMs was (99 +/- 6)%. NP-SIMS showed quantitative sorption of Rh(III) from an HCl medium, the coverage of Im-C11-SH SAMs with Rh(III) was (81.3 +/- 3.8)%. INAA showed quantitative sorption of Ir(IV) and illustrated that it can be adsorbed from a 5.4 mu M initial Ir(IV) solution in 0.55 M HCl on the Im-C11-SH and MDDA SAMs with a surface saturation of (77 +/- 12)% and (84 +/- 16)%, respectively

Influence of dissolved natural organic matter on the mobility of uranium and lanthanides in surface waters of a former U-mining site

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Extraction and separation of iridium(IV) and rhodium(III) from hydrochloric acid media by a quaternary ammonium-based hydrophobic eutectic solvent

International audienceThe extraction and separation of iridium(IV) and rhodium(III) from hydrochloric acid solutions by a hydrophobic eutectic solvent composed of tetraheptylammonium chloride and decanoic acid have been studied for the first time. This eutectic solvent selectively extracts iridium(IV) over rhodium(III), the highest separation factor obtained is approximately 20. The effects of the main experimental factors (shaking time, the volume ratio of aqueous to organic phase, hydrochloric acid concentration, and the initial metal concentration in the aqueous phase) on the extraction behavior of iridium(IV) and rhodium(III) have been investigated. Ultraviolet-visible (UV-Vis) spectroscopy was applied to reveal the [IrCl6]2- complex to be a predominant species attributed to iridium(IV) extraction. To understand the underlying extraction mechanism, the initial iridium(IV) concentration in the aqueous phase has been varied and a corresponding mathematical model has been developed

Deep eutectic solvent pretreatment of biomass: Influence of hydrogen bond donor and temperature on lignin extraction with high β-O-4 content

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Speciation and structure of the Ni(II)/nitrate system in BumimTf2_2N Ionic Liquid

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