Indium and thallium extraction into betainium bis(trifluoromethylsulfonyl)imide ionic liquid from aqueous hydrochloric acid media

International audienc

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

Aqueous N-H acid bis(trifluoromethylsulfonyl) imide Solution - [C4mim][Tf2N] Ionic Liquid Biphasic System: an Original Investigation by Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance

International audienceTransfers of solutes from an aqueous phase to an ionic liquid phase and vice versa has been well studied for years. On the other hand, influence of transferred solutes on the ionic liquid's structure is not yet evaluated. Therefore, we focus on the aqueous-ionic liquid biphasic system composed of two immiscible phase containing N-H acid bis(trifluoromethylsulfonyl) imide and [C 4 mim][Tf 2 N] ionic liquid. After mixing and separation of the two phases, a part of water, H 3 O + , [Tf 2 N-] and H[Tf 2 N] anions were transferred into [C 4 mim][Tf 2 N] ionic liquid phase. The presence of this solutes could modify the local structure of [C 4 mim][Tf 2 N] ionic liquid. So far, our goal is to evaluate this structural change using several tools. For this, one dimensional 1 H, 19 F and Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance were carried out on the [C 4 mim][Tf 2 N] phase. We observed that some of water molecules were free and formed local microstructure as water pocket inside the ionic liquid frame. The others were hydrogen bonded to [Tf 2 N-] anions or H[Tf2N]. The N-H acid bis(trifluoromethylsulfonyl) imide has a salting in effect and the biphasic system turn in a single phase for [H[Tf 2 N]] aq, init = 3 M. The network of [C 4 mim][Tf 2 N] ionic liquid is gradually destroyed when the water brought by the acid H[Tf 2 N] becomes the major species

Les liquides ioniques pour l'extraction liquide-liquide des ions métalliques

International audienc

Aqueous acidic solution - ionic liquid biphasic system: An original investigation by diffusion ordered spectroscopy nuclear magnetic resonance

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Review on Hydrometallurgical Recovery of Metals with Deep Eutectic Solvents

International audienceDeep eutectic solvents (DESs) appeared recently as a new class of green designer solvents. The recovery of metals using hydrometallurgy is of major importance with the growth in metal demand. Several authors used these solvents for the hydrometallurgical recovery of metals from primary and secondary resources, and these studies are reviewed in the present work. Hydrophilic DESs can be used for the leaching of metals and have great potential to replace mineral acids, and even to reduce water consumption. Efficient and selective leaching of metals from minerals or wastes is feasible by using DESs. However, the kinetics of leaching as well as the physicochemical properties of DESs are still limiting their large-scale application. Electrochemical recovery from DES is also possible but deserves further investigation. Finally, the recovery of metals from aqueous solutions using hydrophobic DESs was studied in several works. For the solvent extraction of metals, hydrophobic DESs constitute credible alternative ionic liquids

Solvent extraction of intra-lanthanides using a mixture of TBP and TODGA in ionic liquid

International audienceIn this study, we have investigated the solvent extraction of yttrium(III) and lanthanide(III) ions from nitric acid solutions in an organic phase consisting of a mixture of two electrically neutral extractants, namely tri-n-butyl phosphate(TBP) and N,N,N',N'-tetra(n-octyl)diglycolamide (TODGA). We employed hydrophobic room-temperature ionic liquid 1-methyl-3-butyl-imidazolium bis(trifluoromethanesulfonyl)imide as more environmentally benign diluent as compared to conventional molecular solvents. The results revealed that the addition of TBP as a co-extractant to TODGA dissolved in this ionic liquid not only enhance greatly the metal ion extraction, but also induce high intra-lanthanide ion selectivity. This was attributed to the formation of complex lanthanide species with both organic extracting agents, TBP and TODGA. In addition, when IL is used as diluent, cationic exchange between metal-organic ligand species and IL cations and neutral complex extraction result in more efficient extraction. Moreover, hydrophobic anionic IL entities could be also involved in the extraction mechanism resulting in the lipophilic metal-organic ligand complexes. The synergic solvent combination of TODGA, TBP and ionic liquid offers a possibility of excellent separation among the lanthanide(III) ions

Solvent extraction of lithium from simulated shale gas produced water with a bifunctional ionic liquid

International audienceThe recovery of lithium from brines is a major field of study with an increase in lithium-ion batteries consumption and the subsequent growth of lithium consumption. The recovery of lithium from shale gas produced water is promising since these sources could contain nonnegligible concentrations of lithium. In this study, lithium extraction was investigated using solvent extraction with a bifunctional ionic liquid (IL) as an extracting agent diluted in ndodecane. The components of these IL are cheap and commercially available products, namely Aliquat-336 (methyltrioctylammonium chloride) and DEHPA (di-(2ethylhexyl)phosphoric acid), and its synthesis is straightforward. Lithium extraction was optimized by studying several experimental parameters (mixing time, aqueous phase acidity, IL concentration in the solvent phase, aqueous lithium concentration). The mechanism of extraction was detailed, and the stripping was shown to be complete with 0.5 mol.L-1 of HCl. A two stages strategy was defined to recover lithium from synthetic brine. In the first stage, divalent metals are removed using five successive cycles of extraction with DEHPA (1 mol.L-1) dissolved in n-dodecane. In the second stage, the IL extracting agent [Aliquat-336][DEHPA] (1 mol.L-1) allowed to remove 83% of lithium in one cycle of extraction, which is higher than reported solvent extraction results with conventional extracting molecules

Effect of hydrophobic ionic liquids aqueous solubility on metal extraction from hydrochloric acid media: Mathematical modelling and trivalent thallium behavior

International audienc

Effect of aqueous hydrochloric acid and zwitterionic betaine on the mutual solubility between a protic betainium-based ionic liquid and water

International audienceThe solubility of hydrophobic betainium bis(trifluoromethylsulfonyl)imide ionic liquid in an aqueous phase with controlled acidity has been investigated by a standard liquid-liquid extraction technique. The effect of zwitterionic betaine added into the aqueous phase has also been studied. Quantitative NMR was employed to characterize the distribution behavior of the ionic liquid constituents between the two phases. A mathematical model to describe the ionic liquid solubility in the aqueous phase was developed. This approach was utilized to estimate the conditional solubility product constant of the ionic liquid. The possibility of the transfer of some dissociation products back into the organic phase was investigated. (C) 2018 Elsevier B.V. All rights reserved