Tantalum and Niobium Selective Extraction by Alkyl-Acetophenone

A study has been carried out on Ta and Nb recovery by a liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as the organic phase. The 4-MAcPh was compared to methyl isobutyl ketone (MIBK) with respect to extraction efficiencies (D values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction of Nb for both solvents. However, for Ta, extraction efficiency is increased by a factor of 1.3 for 4-MAcPh. In addition, the MIBK solubilized completely after 6 mol∙L−1 of H2SO4 against only a loss of 0.14–4% for 4-MAcPh between 6 and 9 mol∙L−1 of H2SO4. The potential of 4-MAcPh has also been studied to selectively recover Ta from a model capacitor waste solution. The results showed a selectivity for Ta in the presence of impurities such as Ag, Fe, Ni and Mn. The 4-MAcPh also presents the advantage of having physicochemical properties adapted to its use in liquid-liquid extraction technologies such as mixer-settlers.

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Short Alternative Route for Nuclear Fuel Reprocessing Based on Organic Phase Self-Splitting

Molecules ◽

10.3390/molecules26206234 ◽

2021 ◽

Vol 26 (20) ◽

pp. 6234

Author(s):

Julie Durain ◽

Damien Bourgeois ◽

Murielle Bertrand ◽

Daniel Meyer

Keyword(s):

Organic Phase ◽

Process Development ◽

Temperature Drop ◽

Extraction Process ◽

Liquid Extraction ◽

Nuclear Industry ◽

Process Conditions ◽

Joint Management ◽

Liquid Liquid Extraction ◽

Almost All

A more sustainable management of natural resources and the establishment of processes allowing a joint management of nuclear materials to avoid their diversion from their civilian use are two issues for the nuclear industry. Short alternatives to existing processes have therefore been proposed based on known systems available, tributylphosphate (TBP), for the separation of actinides by liquid/liquid extraction. Proof of concept of such alternative has been established on the uranium(VI)/thorium(IV) system. From an organic phase consisting of a mixture of TBP/n-dodecane loaded with uranium and thorium, two fluxes have been obtained: the first contains almost all of the thorium in the presence of uranium in a controlled ratio, the second contains surplus uranium. Two levers were selected to control the spontaneous separation of the organic phase: the addition of concentrated nitric acid, or the temperature variation. Best results have been obtained using a temperature drop in the liquid/liquid extraction process, and variations in process conditions have been studied. Final metal recovery and solvent recycling have also been demonstrated, opening the door for further process development.

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Origins of Clustering of Metalate-Extractant Complexes in Liquid-Liquid Extraction

10.26434/chemrxiv.13500960 ◽

2020 ◽

Author(s):

Srikanth Nayak ◽

Raju R. Kumal ◽

Zhu Liu ◽

Baofu Qiao ◽

Aurora Clark ◽

...

Keyword(s):

Aqueous Phase ◽

Organic Phase ◽

Langmuir Monolayers ◽

Strong Relationship ◽

Liquid Extraction ◽

Platinum Group Metals ◽

Metal Loading ◽

Liquid Liquid Extraction ◽

Molecular Scale ◽

Dynamics Simulations

Effective and energy efficient separation of precious and rare metals is very important for a variety of advanced technologies. Liquid-liquid extraction (LLE) is a relatively less energy intensive separation technique, widely used in separation of lanthanides, actinides, and platinum group metals (PGMs). In LLE, the distribution of an ion between an aqueous phase and an organic phase is determined by enthalpic (coordination interactions) and entropic (fluid reorganization) contributions. The molecular scale details of these contributions are not well understood. Preferential extraction of an ion from the aqueous phase is usually correlated with the resulting fluid organization in the organic phase, as the longer-range organization increases with metal loading. However, it is difficult to determine the extent to which organic phase fluid organization causes, or is caused by, metal loading. In this study, we demonstrate that two systems with the same metal loading may impart very different organic phase organization; and investigate the underlying molecular scale mechanism. Small angle X-ray scattering shows that the structure of a quaternary ammonium extractant solution in toluene is affected differently by the extraction of two metalates (octahedral PtCl62- and square-planar PdCl42-), although both are completely transferred into the organic phase. The aggregates formed by the metalate-extractant complexes (approximated as reverse micelles) exhibit more long-range order (clustering) with PtCl62- compared to that with PdCl42-. Vibrational sum frequency generation spectroscopy, and complimentary atomistic molecular dynamics simulations on model Langmuir monolayers, indicate that the two metalates affect the interfacial hydration structures differently. These results support a strong relationship between the organic phase organizational structure and different local hydration present within the aggregates of metalate-extractant complexes, which is independent of metalate concentration.

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Determination of formation constants of uranyl(VI) complexes with a hydrophilic SO3-Ph-BTP ligand, using liquid-liquid extraction

Nukleonika ◽

10.1515/nuka-2015-0150 ◽

2015 ◽

Vol 60 (4) ◽

pp. 821-827 ◽

Cited By ~ 3

Author(s):

Lukasz Steczek ◽

Jerzy Narbutt ◽

Marie-Christine Charbonnel ◽

Philippe Moisy

Keyword(s):

Aqueous Phase ◽

Strong Dependence ◽

Free Ligand ◽

Formation Constants ◽

Extraction Process ◽

Uranyl Complex ◽

Liquid Extraction ◽

Liquid Liquid Extraction ◽

Liquid Phases ◽

D Values

Abstract Complex formation between uranyl ion, UO22+, and a hydrophilic anionic form of SO3-Ph-BTP4- ligand, L4-, in water was studied by liquid-liquid extraction experiments performed over a range of the ligand and HNO3 concentrations in the aqueous phase, at a constant concentration of nitrate anions at 25°C . The competition for UO22+ ions between the lipophilic TODGA extractant and the hydrophilic L4- ligand leads to the decrease in the uranyl distribution ratios, D, with an increasing L4- concentration. The model of the solvent extraction process used accounts - apart from uranyl complexation by TODGA and SO3-Ph-BTP4- - also for uranyl complexation by nitrates and for the decrease in the concentration of the free L4- ligand in the aqueous phase, due to its protonation, bonding in the uranyl complex and the distribution between the two liquid phases. The unusually strong dependence of the D values on the acidity, found in the experiment, could hardly be explained as due to L4- protonation merely. Three hypotheses were experimentally tested, striving to interpret the data in terms of additional extraction to the organic phase of ion associates of protonated TODGA cation with either partly protonated anionic L4- ligands or anionic UO22+ complexes with NO3 - or L4-. None of them has been confirmed. The analysis of the results, based on the formal correction of free ligand concentrations, points to the formation of 1 : 1 and 1 : 2 uranyl - SO3-Ph-BTP complexes in the aqueous phase. The conditional formation constant of the 1:1 complex has been determined, logßL,1 = 2.95 ± 0.15.

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Origins of Clustering of Metalate-Extractant Complexes in Liquid-Liquid Extraction

10.26434/chemrxiv.13500960.v1 ◽

2020 ◽

Author(s):

Srikanth Nayak ◽

Raju R. Kumal ◽

Zhu Liu ◽

Baofu Qiao ◽

Aurora Clark ◽

...

Keyword(s):

Aqueous Phase ◽

Organic Phase ◽

Langmuir Monolayers ◽

Strong Relationship ◽

Liquid Extraction ◽

Platinum Group Metals ◽

Metal Loading ◽

Liquid Liquid Extraction ◽

Molecular Scale ◽

Dynamics Simulations

Effective and energy efficient separation of precious and rare metals is very important for a variety of advanced technologies. Liquid-liquid extraction (LLE) is a relatively less energy intensive separation technique, widely used in separation of lanthanides, actinides, and platinum group metals (PGMs). In LLE, the distribution of an ion between an aqueous phase and an organic phase is determined by enthalpic (coordination interactions) and entropic (fluid reorganization) contributions. The molecular scale details of these contributions are not well understood. Preferential extraction of an ion from the aqueous phase is usually correlated with the resulting fluid organization in the organic phase, as the longer-range organization increases with metal loading. However, it is difficult to determine the extent to which organic phase fluid organization causes, or is caused by, metal loading. In this study, we demonstrate that two systems with the same metal loading may impart very different organic phase organization; and investigate the underlying molecular scale mechanism. Small angle X-ray scattering shows that the structure of a quaternary ammonium extractant solution in toluene is affected differently by the extraction of two metalates (octahedral PtCl62- and square-planar PdCl42-), although both are completely transferred into the organic phase. The aggregates formed by the metalate-extractant complexes (approximated as reverse micelles) exhibit more long-range order (clustering) with PtCl62- compared to that with PdCl42-. Vibrational sum frequency generation spectroscopy, and complimentary atomistic molecular dynamics simulations on model Langmuir monolayers, indicate that the two metalates affect the interfacial hydration structures differently. These results support a strong relationship between the organic phase organizational structure and different local hydration present within the aggregates of metalate-extractant complexes, which is independent of metalate concentration.

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Separation of no-carrier-added 71,72As from 46 MeV alpha particle irradiated gallium oxide target

Radiochimica Acta ◽

10.1515/ract-2020-0120 ◽

2021 ◽

Vol 109 (5) ◽

pp. 389-395

Author(s):

Nabanita Naskar ◽

Susanta Lahiri

Keyword(s):

Aqueous Phase ◽

Organic Phase ◽

Alpha Particle ◽

Gallium Oxide ◽

Complete Separation ◽

Liquid Extraction ◽

Aliquat 336 ◽

Liquid Liquid Extraction ◽

Target Matrix ◽

No Carrier Added

Abstract No-carrier-added (NCA) 71,72As radionuclides were produced by irradiating gallium oxide target by 46 MeV α-particles. NCA 71,72As was separated from the target matrix by liquid-liquid extraction (LLX) using trioctyl amine (TOA) and tricaprylmethylammonium chloride (aliquat-336) diluted in cyclohexane. The bulk gallium was quantitatively extracted into the organic phase leaving 71,72As in the aqueous phase. Complete separation was observed at 3 M HCl + 0.1 M TOA and 2 M HCl + 0.01 M aliquat-336.

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Liquid-Liquid Extraction of Transition Metal Cations by Glyoximes and Their Macrocyclic Glyoxime Ether Derivatives

Journal of Chemistry ◽

10.1155/2013/187572 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Nazan Karapinar ◽

Emin Karapinar ◽

Emine Ozcan

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Crown Ether ◽

Aqueous Phase ◽

Organic Phase ◽

Equilibrium Constants ◽

Liquid Extraction ◽

Extraction Equilibrium ◽

Liquid Liquid Extraction ◽

Extraction Constants

Liquid-liquid extraction of various alkalis (Li+, Na+, K+, and Cs+), transition metals (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+), and Pb2+cations with phenylglyoxime (L1), p-tolylglyoxime (L2),N′-(4′-Benzo[15-crown-5])phenylaminoglyoxime (L3), andN′-(4′-Benzo[15-crown-5])-p-tolylaminoglyoxime (L4) from the aqueous phase into the organic phase was carried out. For comparison, the corresponding two glyoximes and their macrocyclic glyoxime ether derivatives were also examined. Crown ether groups having ligands (L3,L4) carry especially Na+cation from aqueous phase to organic phase. The extraction equilibrium constants (Kex) for complexes of ligands with Cu2+and Hg2+metal picrates between dichloromethane and water have been determined at 25°C. The values of the extraction constants (logKex) were determined to be 12.27, 13.37, 12.94, and 12.39 for Cu2+and 10.29, 10.62, 11.53, and 11.97 for Hg2+with L1–L4, respectively.

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The recovery of rare earth metals from WEEE leaching solution via liquid-liquid extraction

Global NEST Journal ◽

10.30955/gnj.002646 ◽

2018 ◽

Vol 20 (4) ◽

pp. 719-724 ◽

Cited By ~ 1

Keyword(s):

Rare Earth ◽

Oxalic Acid ◽

Organic Phase ◽

Electronic Waste ◽

Rare Earth Metals ◽

Extraction Process ◽

Liquid Extraction ◽

The Sustainable Development ◽

Liquid Liquid Extraction ◽

Leaching Solution

The recovery of rare earth metals (REMs) from end-of-life products, such as Waste Electrical and Electronic Equipment (WEEE), is drawing great attention as an attractive strategy for promoting the sustainable development. The hydrometallurgical technique of solvent extraction has been reported to be one of the most interesting method to recover REMs. However, when applied to WEEE, this process is challenged by the heterogeneous composition of electronic waste, completely different from other solid matrices, and it still has much rooms of improvements. This study investigated the extraction, stripping and recovery of REMs from a WEEE leaching solution using Versatic 10 as carrier in the organic phase and oxalic acid as stripping agent. A factorial design was carried out to evaluate the simultaneous effects of factors as the feed phase pH and the concentrations of both extractant and organic phase modifier in the extraction process. Cerium, lanthanum and yttrium were extracted at high percentages using 200 mM of Versatic 10, loaded by 100 mM of TBP in kerosene at pH 7. Moreover, 750 mM of oxalic acid successfully stripped and recovered 7.63 and 13.82 mg/kg of lanthanum and yttrium, respectively.

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Origins of Clustering of Metalate-Extractant Complexes in Liquid-Liquid Extraction

10.26434/chemrxiv.13500960.v2 ◽

2021 ◽

Author(s):

Srikanth Nayak ◽

Raju R. Kumal ◽

Zhu Liu ◽

Baofu Qiao ◽

Aurora Clark ◽

...

Keyword(s):

Aqueous Phase ◽

Organic Phase ◽

Langmuir Monolayers ◽

Strong Relationship ◽

Liquid Extraction ◽

Platinum Group Metals ◽

Metal Loading ◽

Liquid Liquid Extraction ◽

Molecular Scale ◽

Dynamics Simulations

Effective and energy efficient separation of precious and rare metals is very important for a variety of advanced technologies. Liquid-liquid extraction (LLE) is a relatively less energy intensive separation technique, widely used in separation of lanthanides, actinides, and platinum group metals (PGMs). In LLE, the distribution of an ion between an aqueous phase and an organic phase is determined by enthalpic (coordination interactions) and entropic (fluid reorganization) contributions. The molecular scale details of these contributions are not well understood. Preferential extraction of an ion from the aqueous phase is usually correlated with the resulting fluid organization in the organic phase, as the longer-range organization increases with metal loading. However, it is difficult to determine the extent to which organic phase fluid organization causes, or is caused by, metal loading. In this study, we demonstrate that two systems with the same metal loading may impart very different organic phase organization; and investigate the underlying molecular scale mechanism. Small angle X-ray scattering shows that the structure of a quaternary ammonium extractant solution in toluene is affected differently by the extraction of two metalates (octahedral PtCl62- and square-planar PdCl42-), although both are completely transferred into the organic phase. The aggregates formed by the metalate-extractant complexes (approximated as reverse micelles) exhibit more long-range order (clustering) with PtCl62- compared to that with PdCl42-. Vibrational sum frequency generation spectroscopy, and complimentary atomistic molecular dynamics simulations on model Langmuir monolayers, indicate that the two metalates affect the interfacial hydration structures differently. Further, the interfacial hydration is correlated with water extraction into the organic phase. These results support a strong relationship between the organic phase organizational structure and different local hydration present within the aggregates of metalate-extractant complexes, which is independent of metalate concentration.

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Efficient trace-scale extraction method of reactor produced 199Au adequate for nuclear medicine applications

Radiochimica Acta ◽

10.1515/ract-2020-0108 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Mohamed F. Attallah ◽

Ahmed M. Shahr El-Din ◽

Mohamed A. Gizawy ◽

Amal M. I. Ali

Keyword(s):

Aqueous Media ◽

Selective Extraction ◽

Extraction Process ◽

High Yield ◽

High Recovery ◽

Rapid Separation ◽

Efficient Separation ◽

Liquid Liquid Extraction ◽

Cyanex 302 ◽

Cyanex 923

Abstract Production of no carrier-added (NCA) 199Au through natPt(n, γ) reaction and subsequent purification using liquid-liquid extraction from other radioisotopes is studied in the context of theranostic application. Comparative separation of NCA 199Au after dissolution of activated Pt target using three Cyanex compounds (Cyanex-272, Cyanex-302 and Cyanex-923) is evaluated. The extraction process is optimized in terms of the type of extractant, the concentration of extractant, extraction time and aqueous media (HNO3, NH4OH). Among these extractants, the Cynaex-923 is efficient and promising for rapid separation and production of NCA 199Au from HNO3 by high extraction %. Selective extraction of 199Au from other Pt and Ir radioisotopes is observed. High recovery of 199Au was obtained in the case of Cyanex-923 using 0.05 M thiourea dissolved in HCl or 2 M NaOH. Our results find the Cyanex-923 as a promising extractant for efficient separation of 199Au from irradiated Pt target with high yield (99%).

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