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Lapo B, Pavón S, Hoyo J, Fortuny A, Scapan P, Bertau M, Sastre AM. Bioderived Pickering Emulsion Based on Chitosan/Trialkyl Phosphine Oxides Applied to Selective Recovery of Rare Earth Elements. ACS APPLIED MATERIALS & INTERFACES 2023; 15:59731-59745. [PMID: 38091526 PMCID: PMC10802976 DOI: 10.1021/acsami.3c10233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 11/23/2023] [Accepted: 11/27/2023] [Indexed: 12/28/2023]
Abstract
A novel biobased pickering emulsion (PE) material was prepared by the encapsulation of Cyanex 923 (Cy923) into chitosan (CS) to selectively recover rare earth elements (REEs) from the aqueous phase. The preparation of PE was optimized through sequentially applying a 23 full factorial design, followed by a 33 Box-Behnken design varying the Cy923 content, CS concentration, and pH of CS. The material was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), optical microscopy, rheological, compositional, and stability measurements. The resultant material was evaluated in the removal of yttrium by pH influence, nitrate concentration, kinetics, equilibrium isotherms, reusability, and a comparison with liquid-liquid (L-L) extraction and tested in a real scenario to extract Y from a fluorescent lamp powder waste. In addition, the selectivity of PE for REE was investigated with Y/Ca, Gd/Ca, and La/Ni systems. PE extracts REE at 1 ≤ pH ≤ 5 at nitrate concentrations up to 2 mol/L. The kinetics and equilibrium studies showed reaction times <5 min and a maximum sorption capacity of 89.98 mg/g. Compared with L-L extraction, PE consumed 48% less Cy923 without using organic diluents. PE showed a remarkable selectivity for REE in the systems evaluated, showing separation factors of 22.62, 9.35, and 504.64 for the blends Y/Ca, Gd/Ca/Mg, and La/Ni, respectively. PE showed excellent selectivity extracting Y from a real aqueous liquor from the fluorescent lamp powder. PE demonstrates to be an effective and sustainable alternative for REE recovering due to its excellent efficiency in harsh conditions, favorable green chemistry metrics, and use of a biopolymer material in its composition avoiding the use of organic solvents used in L-L extraction.
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Affiliation(s)
- Byron Lapo
- Department
of Chemical Engineering, Universitat Politècnica
de Catalunya, EPSEVG, Av. Víctor Balaguer 01, 08800 Vilanova i la Geltrú, Spain
- School
of Chemical Engineering, Technical University
of Machala, UACQS, BIOeng, 070151 Machala, Ecuador
- Institute
of Chemical Technology, TU Bergakademie
Freiberg, Leipziger Straße
29, Freiberg 09599, Germany
| | - Sandra Pavón
- Institute
of Chemical Technology, TU Bergakademie
Freiberg, Leipziger Straße
29, Freiberg 09599, Germany
- Fraunhofer
Institute for Ceramic Technologies and Systems IKTS; Fraunhofer Technology Center for High-Performance Materials THM, Am St.-Niclas-Schacht 13, 09599 Freiberg, Germany
| | - Javier Hoyo
- Department
of Physical-Chemistry, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Agustín Fortuny
- Department
of Chemical Engineering, Universitat Politècnica
de Catalunya, EPSEVG, Av. Víctor Balaguer 01, 08800 Vilanova i la Geltrú, Spain
| | - Paul Scapan
- Institute
of Chemical Technology, TU Bergakademie
Freiberg, Leipziger Straße
29, Freiberg 09599, Germany
| | - Martin Bertau
- Institute
of Chemical Technology, TU Bergakademie
Freiberg, Leipziger Straße
29, Freiberg 09599, Germany
- Fraunhofer
Institute for Ceramic Technologies and Systems IKTS; Fraunhofer Technology Center for High-Performance Materials THM, Am St.-Niclas-Schacht 13, 09599 Freiberg, Germany
| | - Ana María Sastre
- Department
of Chemical Engineering, Universitat Politècnica
de Catalunya, ETSEIB,
Diagonal 647, 08028 Barcelona, Spain
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Atanassova M, Kurteva V. Mutual Solubilities between Ethylene Glycol and Organic Diluents: Gas Chromatography and NMR. Molecules 2023; 28:5121. [PMID: 37446785 DOI: 10.3390/molecules28135121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
In this work, the mutual solubilities of sets of organic diluents (CHCl3, C6H6, C2H4Cl2, CCl4, C6H12, and n-hexane) with the organic compound ethylene glycol are investigated via gas chromatography (GC). The experimental data measured for these binary organic systems are used to adjust the future nonaqueous systems for the solvent extraction of various metals with ligands. The obtained results showed that the solubility of ethylene glycol decreased in the order CHCl3 > C6H6 > C2H4Cl2 > CCl4(0%) ≈ C6H12 ≈ n-hexane. On the other hand, the solubility of the tested traditional organic diluents in ethylene glycol decreased in the following order: C6H6 > CHCl3 > C2H4Cl2 > n-hexane > C6H12 > CCl4. 1H NMR was also used as an analytic method in order to compare the obtained results for the samples showing significant solubility only, including an additional study with 1,2- or 1,3-propanediol. The enhanced solubility of the C6H6 compound in ethylene glycol was identified here as critical due to the GC technique, which will be without future consequences in chemical technology. Therefore, it was found that the best molecular diluent for the recovery of metals among the tested ones is C6H12, with a green protocol as the new paradigm, replacing the aqueous phase with another nonaqueous phase, i.e., a second organic diluent.
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Affiliation(s)
- Maria Atanassova
- Department of General and Inorganic Chemistry, University of Chemical Technology and Metallurgy, 8 Kliment Okhridski Blvd., 1756 Sofia, Bulgaria
| | - Vanya Kurteva
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Block 9, 1113 Sofia, Bulgaria
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Zhang Z, Liu J, Li T, Fu Z, Mao J, Li X, Ren S. High-efficient and selective separation of dysprosium and neodymium from polyethylene glycol 200 solution by non-aqueous solvent extraction with P350. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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Applied novel functionality in separation procedure from leaching solution of zinc plant residue by using non-aqueous solvent extraction. Sci Rep 2023; 13:1146. [PMID: 36670143 PMCID: PMC9860044 DOI: 10.1038/s41598-023-27646-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 01/05/2023] [Indexed: 01/22/2023] Open
Abstract
Traditional solvent extraction (SX) procedures limit metal separation and purification, which consist of the organic and aqueous phases. Because differences in metal ion solvation lead to distinct distribution properties, non-aqueous solvent extraction (NASX) considerably expands the scope of solvent extraction by replacing the aqueous phase with alternate polar solvents. In this study, an experimental design approach used non-aqueous solvent extraction to extract cobalt from zinc plant residue. The aqueous phase comprises ethylene glycol (EG), LiCl and metal ions. In kerosene, D2EHPA, Cyanex272, Cyanex301, and Cyanex302 extractants were used as a less polar organic phase. Various factors were investigated to see how they affected extraction, including solvent type, extractant type and phase ratio, pH, Co(II) concentration, and temperature. The results revealed that at a concentration of 0.05 M, the Cyanex301 extractant could achieve the requisite extraction efficiency in kerosene. The optimal conditions were chosen as the concentration of Cyanex 301 (0.05 M), the concentration of cobalt (833 ppm), the pH (3.5), and the percent of EG (80%). As a result, during the leaching process, these systems are advised for extracting and separating a combination of various metal ions.
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Falco A, Neri M, Melegari M, Baraldi L, Bonfant G, Tegoni M, Serpe A, Marchiò L. Semirigid Ligands Enhance Different Coordination Behavior of Nd and Dy Relevant to Their Separation and Recovery in a Non-aqueous Environment. Inorg Chem 2022; 61:16110-16121. [PMID: 36177719 PMCID: PMC9554911 DOI: 10.1021/acs.inorgchem.2c02619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Rare-earth elements are widely used in high-end technologies,
the
production of permanent magnets (PMs) being one of the sectors with
the greatest current demand and likely greater future demand. The
combination of Nd and Dy in NdFeB PMs enhances their magnetic properties
but makes their recycling more challenging. Due to the similar chemical
properties of Nd and Dy, their separation is expensive and currently
limited to the small scale. It is therefore crucially important to
devise efficient and selective methods that can recover and then reuse
those critical metals. To address these issues, a series of heptadentate
Trensal-based ligands were used for the complexation of Dy3+ and Nd3+ ions, with the goal of indicating the role of
coordination and solubility equilibria in the selective precipitation
of Ln3+–metal complexes from multimetal non-water
solutions. Specifically, for a 1:1 Nd/Dy mixture, a selective and
fast precipitation of the Dy complex occurred in acetone with the
Trensalp-OMe ligand at room temperature,
with a concomitant enrichment of Nd in the solution phase. In acetone,
complexes of Nd and Dy with Trensalp-OMe were characterized by very similar formation constants of 7.0(2)
and 7.3(2), respectively. From the structural analysis of an array
of Dy and Nd complexes with TrensalR ligands, we showed
that Dy invariably provided complexes with coordination number (cn)
of 7, whereas the larger Nd experienced an expansion of the coordination
sphere by recruiting additional solvent molecules and giving a cn
of >7. The significant structural differences have been identified
as the main premises upon which a suitable separation strategy can
be devised with these kind of ligands, as well as other preorganized
polydentate ligands that can exploit the small differences in Ln3+ coordination requirements. Heptadentate
TrensalR-based ligands were complexed
with Dy3+ and Nd3+ cations. Dy compounds exhibited
an invariable coordination number of 7. Nd complexes presented a coordination
number of ≥8, with the metal having additional solvent or water
molecules in the coordination sphere. The ligand Trensalp-OMe led to a selective precipitation of the
Dy complex in acetone, with a concomitant enrichment of Nd in the
solution phase.
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Affiliation(s)
- Alex Falco
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Martina Neri
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Matteo Melegari
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Laura Baraldi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Giulia Bonfant
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Matteo Tegoni
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
| | - Angela Serpe
- Department of Civil and Environmental Engineering and Architecture (DICAAR) and Research Unit of INSTM, University of Cagliari, Via Marengo 2, 09123 Cagliari, Italy.,Environmental Geology and Geoengineering Institute of the National Research Council (IGAG-CNR), Piazza d'Armi, 09123 Cagliari, Italy
| | - Luciano Marchiò
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124, Parma, Italy
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Effect of polar molecular organic solvents on non-aqueous solvent extraction of rare-earth elements. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Dewulf B, Riaño S, Binnemans K. Separation of heavy rare-earth elements by non-aqueous solvent extraction: Flowsheet development and mixer-settler tests. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120882] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Amjad RS, Torkaman R, Asadollahzadeh M. Evaluation of effective parameters on the non-aqueous solvent extraction of samarium and gadolinium to n-dodecane/D2EHPA. PROGRESS IN NUCLEAR ENERGY 2022. [DOI: 10.1016/j.pnucene.2021.104072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Li Z, Dewulf B, Binnemans K. Nonaqueous Solvent Extraction for Enhanced Metal Separations: Concept, Systems, and Mechanisms. Ind Eng Chem Res 2021; 60:17285-17302. [PMID: 34898845 PMCID: PMC8662634 DOI: 10.1021/acs.iecr.1c02287] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 10/06/2021] [Accepted: 10/27/2021] [Indexed: 11/30/2022]
Abstract
Efficient and sustainable separation of metals is gaining increasing attention, because of the essential roles of many metals in sustainable technologies for a climate-neutral society, such as rare earths in permanent magnets and cobalt, nickel, and manganese in the cathode materials of lithium-ion batteries. The separation and purification of metals by conventional solvent extraction (SX) systems, which consist of an organic phase and an aqueous phase, has limitations. By replacing the aqueous phase with other polar solvents, either polar molecular organic solvents or ionic solvents, nonaqueous solvent extraction (NASX) largely expands the scope of SX, since differences in solvation of metal ions lead to different distribution behaviors. This Review emphasizes enhanced metal extraction and remarkable metal separations observed in NASX systems and discusses the effects of polar solvents on the extraction mechanisms according to the type of polar solvents and the type of extractants. Furthermore, the considerable effects of the addition of water and complexing agents on metal separations in terms of metal ion solvation and speciation are highlighted. Efforts to integrate NASX into metallurgical flowsheets and to develop closed-loop solvometallurgical processes are also discussed. This Review aims to construct a framework of NASX on which many more studies on this topic, both fundamental and applied, can be built.
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Affiliation(s)
| | | | - Koen Binnemans
- Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Heverlee, Belgium
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10
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Rizk S, Gamal R, El-Hefny N. Insights into non-aqueous solvent extraction of gadolinium and neodymium from ethylene glycol solution using Cyanex 572. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Recycling of rare earths from fluorescent lamp waste by the integration of solid-state chlorination, leaching and solvent extraction processes. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118879] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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12
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Sui N, Huang K. Study on the interfacial behaviors for extraction of heavy rare earths with PC-88A: A new strategy of thin oil film extraction. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Li Z, Zhang Z, Onghena B, Li X, Binnemans K. Ethylammonium nitrate enhances the extraction of transition metal nitrates by tri- n-butyl phosphate (TBP). AIChE J 2021; 67:e17213. [PMID: 34219743 PMCID: PMC8244074 DOI: 10.1002/aic.17213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 01/08/2021] [Accepted: 01/18/2021] [Indexed: 12/31/2022]
Abstract
Several molecular polar solvents have been used as solvents of the more polar phase in the solvent extraction (SX) of metals. However, the use of hydrophilic ionic liquids (ILs) as solvents has seldomly been explored for this application. Here, the hydrophilic IL ethylammonium nitrate (EAN), has been utilized as a polar solvent in SX of transition metal nitrates by tri-n-butyl phosphate (TBP). It was found that the extraction from EAN is considerably stronger than that from a range of molecular polar solvents. The main species of Co(II) and Fe(III) in EAN are likely [Co(NO3)4]2- and [Fe(NO3)4]-, respectively. The extracted species are likely Fe(TBP)3(NO3)3 and a mixture of Co(TBP)2(NO3)2 and Co(TBP)3(NO3)2. The addition of H2O or LiCl to EAN reduces the extraction because the metal cations coordinate to water molecules and chloride ions stronger than to nitrate ions. This study highlights the potential of using hydrophilic ILs to enhance SX of metals.
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Affiliation(s)
- Zheng Li
- Department of ChemistryKU LeuvenHeverleeBelgium
| | - Zidan Zhang
- Department of Chemical EngineeringUniversity of Texas at AustinAustinTexasUSA
| | | | - Xiaohua Li
- Department of ChemistryKU LeuvenHeverleeBelgium
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Fazil S, Menaa F, Liaqat K, Khan MH, Rehman W, Khan MM, Siraj Ul Haq, Sajid M, Farooq M, Menaa B, Hafeez M. Synergistic Extraction of Europium (III) using Di-n-Butylsulfoxide and PicrolonicAcid. Comb Chem High Throughput Screen 2021; 25:861-869. [PMID: 33568027 DOI: 10.2174/1386207324666210210105511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 01/05/2021] [Accepted: 01/17/2021] [Indexed: 11/22/2022]
Abstract
AIM AND OBJECTIVE Europium (Eu(III))isa rare-earth metal, the softest, least dense, and most volatile member of lanthanides. It is greatly applied in control rods of nuclear reactors. Although various extraction methods of Eu(III)have been reported, we present a novel mixture ofeasily available extractants in optimizedexperimental conditions to extract it efficiently, quickly, and cost-effectively. MATERIALS AND METHODS Physical-chemical conditions (e.g. pH, equilibration time, temperature, europium concentration, extractants concentration, presence of specific metal ions) were optimized. The extractantspicrolonic acid (HPA) and di-n-butylsulfoxide (DBSO) were thoroughly mixed at equal concentrationin chloroform. Standard Eu(III) solution was used for method accuracy.Reagent blank was prepared under identical conditions but without metal ions.Using the metallochromic dye arsenazoIII as blank, absorbance of Eu(III) was measured spectrophotometricallyat 651 nm. Distribution ratio (i.e.Eu(III) concentration in aqueous phase before and after extraction) defined the extraction yield. RESULTS HPA/DBSO mixture (0.01 M)had a synergistic effect on Eu(III) extraction (1.19×10-5 mole/dm3) achieving a maximum yield (≥99%) at pH2, during 5 minutes equilibration,atroom temperature.Eu(III) extraction was reduced depending on the nature but not on the metal ions concentration. Extractants could be recycled four times without consequent degradation. Deionized water (dH2O) was the best strippantbesides its availability and low-cost. The composition of the extracted adduct was defined as Eu(PA)3.2DBSO. CONCLUSION This alternative method was stable, simple, rapid, cost-effective, reliable, accurate and sensitive.It could be used forEu(III) extraction and refining on a pilot plant scale.
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Affiliation(s)
- Srosh Fazil
- Department of Chemistry, University of Poonch Rawalakot, Azad Kashmir. Pakistan
| | - Farid Menaa
- Department of Chemistry and Nanomedicine, California Innovations Corporation, San Diego, CA. United States
| | - Khurram Liaqat
- Department of Chemistry, Hazara University, Mansehra, KPK. Pakistan
| | - Muhammad Haleem Khan
- Department of Chemistry, University of Azad Jammu & Kashmir, Muzaffarabad. Pakistan
| | - Wajid Rehman
- Department of Chemistry, Hazara University, Mansehra, KPK. Pakistan
| | - Mohammad Mansoob Khan
- Chemical Sciences, Faculty of Sciences, University Brunei Darussalam, Jalan Tungku Link, Gadong, BE 1410. Brunei Darussalam
| | - Siraj Ul Haq
- Department of Chemistry, University of Azad Jammu & Kashmir, Muzaffarabad. Pakistan
| | - Muhammad Sajid
- 6Department of Biochemistry, Hazara University, Mansehra, KPK. Pakistan
| | - Muhammad Farooq
- Department of Physics, Hazara University, Mansehra, KPK. Pakistan
| | - Bouzid Menaa
- Department of Chemistry and Nanomedicine, California Innovations Corporation, San Diego, CA. United States
| | - Muhammad Hafeez
- Department of Chemistry, University of Azad Jammu & Kashmir, Muzaffarabad . Pakistan
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Batchu NK, Li Z, Verbelen B, Binnemans K. Structural effects of neutral organophosphorus extractants on solvent extraction of rare-earth elements from aqueous and non-aqueous nitrate solutions. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117711] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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16
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Dewulf B, Batchu NK, Binnemans K. Enhanced Separation of Neodymium and Dysprosium by Nonaqueous Solvent Extraction from a Polyethylene Glycol 200 Phase Using the Neutral Extractant Cyanex 923. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2020; 8:19032-19039. [PMID: 33457111 PMCID: PMC7807624 DOI: 10.1021/acssuschemeng.0c07207] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Neodymium and dysprosium can be efficiently separated by solvent extraction, using the neutral extractant Cyanex 923, if the conventional aqueous feed phase is largely replaced by the green polar organic solvent polyethylene glycol 200 (PEG 200). While pure aqueous and pure PEG 200 solutions in the presence of LiCl or HCl were not able to separate the two rare earth elements, high separation factors were observed when extraction was performed from PEG 200 chloride solutions with addition of small amounts of water. This addition of water bridges the gap between traditional hydrometallurgy and novel solvometallurgy and overcomes the challenges faced in both methods. The effect of different variables was investigated: water content, chloride concentration, type of chloride salt, Cyanex 923 concentration, scrubbing agent. A Job plot revealed the extraction stoichiometry is DyCl3·4L, where L is Cyanex 923. The McCabe-Thiele diagram for dysprosium extraction showed that complete extraction of this metal can be achieved by a 3-stage counter-current solvent extraction process, leaving neodymium behind in the raffinate. Finally, a conceptual flow sheet for the separation of neodymium and dysprosium including extraction, scrubbing, stripping, and regeneration steps was presented. The nonaqueous solvent extraction process presented in this paper can contribute to efficient recycling of rare earths from end-of-life neodymium-iron-boron (NdFeB) magnets.
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Affiliation(s)
- Brecht Dewulf
- KU Leuven, Department of Chemistry, Celestijnenlaan 200F, P.O. Box
2404, B-3001 Leuven, Belgium
| | - Nagaphani Kumar Batchu
- KU Leuven, Department of Chemistry, Celestijnenlaan 200F, P.O. Box
2404, B-3001 Leuven, Belgium
| | - Koen Binnemans
- KU Leuven, Department of Chemistry, Celestijnenlaan 200F, P.O. Box
2404, B-3001 Leuven, Belgium
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17
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Li Z, Binnemans K. Hydration counteracts the separation of lanthanides by solvent extraction. AIChE J 2020; 66:e16545. [PMID: 35859698 PMCID: PMC9285791 DOI: 10.1002/aic.16545] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/15/2020] [Accepted: 06/28/2020] [Indexed: 01/17/2023]
Abstract
The extraction of lanthanides from aqueous nitrate solutions by quaternary ammonium nitrate ionic liquids (e.g., [A336][NO3]) shows a negative sequence (i.e., light lanthanides are more efficiently extracted than heavy lanthanides), which conflicts with the lanthanide contraction. In this study, we explored the origin of the negative sequence by investigating the extraction of lanthanides from ethylammonium nitrate by [A336][NO3]. The extraction shows a positive sequence, which is converted to a negative sequence with the addition of water. The transformation from positive to negative sequences reveals that the negative sequence is caused by the hydration of lanthanide ions: hydration of lanthanide ions counteracts the extraction. Therefore, the use of solvents that have weak solvation with lanthanide ions might enhance the separation of the elements by solvent extraction.
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Affiliation(s)
- Zheng Li
- Department of ChemistryKU Leuven Heverlee Belgium
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18
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Deferm C, Onghena B, Nguyen VT, Banerjee D, Fransaer J, Binnemans K. Non-aqueous solvent extraction of indium from an ethylene glycol feed solution by the ionic liquid Cyphos IL 101: speciation study and continuous counter-current process in mixer-settlers. RSC Adv 2020; 10:24595-24612. [PMID: 35516195 PMCID: PMC9055152 DOI: 10.1039/d0ra04684a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 06/16/2020] [Indexed: 12/25/2022] Open
Abstract
A solvometallurgical process for the separation of indium(iii) and zinc(ii) from ethylene glycol solutions using the ionic liquid extractants Cyphos IL 101 and Aliquat 336 in an aromatic diluent has been investigated. The speciation of indium(iii) in the two immiscible organic phases was investigated by Raman spectroscopy, infrared spectroscopy, EXAFS and 115In NMR spectroscopy. At low LiCl concentrations in ethylene glycol, the bridging (InCl3)2(EG)3 or mononuclear (InCl3)(EG)2 complex is proposed. At higher lithium chloride concentrations, the first coordination sphere changes to two oxygen atoms from one bidentate ethylene glycol ligand and four chloride anions ([In(EG)Cl4]-). In the less polar phase, indium(iii) is present as a tetrahedral [InCl4]- complex independent of the LiCl concentration. After the number of theoretical stages had been determined using a McCabe-Thiele diagram for extraction by Cyphos IL 101, the extraction and scrubbing processes were performed in lab-scale mixer-settlers to test the feasibility of working in continuous mode. Indium(iii) was extracted quantitatively in four stages, with 19% co-extraction of zinc(ii). The co-extracted zinc(ii) was scrubbed selectively in six stages using an indium(iii) scrub solution. Indium(iii) was recovered from the loaded less polar organic phase as indium(iii) hydroxide (98.5%) by precipitation stripping with an aqueous NaOH solution.
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Affiliation(s)
- Clio Deferm
- KU Leuven, Department of Chemistry Celestijnenlaan 200F, P.O. box 2404 B-3001 Leuven Belgium
| | - Bieke Onghena
- KU Leuven, Department of Chemistry Celestijnenlaan 200F, P.O. box 2404 B-3001 Leuven Belgium
| | - Viet Tu Nguyen
- KU Leuven, Department of Chemistry Celestijnenlaan 200F, P.O. box 2404 B-3001 Leuven Belgium
| | - Dipanjan Banerjee
- KU Leuven, Department of Chemistry Celestijnenlaan 200F, P.O. box 2404 B-3001 Leuven Belgium
- Dutch-Belgian Beamline (DUBBLE), ESRF - The European Synchrotron CS 40220 F-38043 Grenoble Cedex 9 France
| | - Jan Fransaer
- KU Leuven, Department of Materials Engineering Kasteelpark Arenberg 44, bus 2450 B-3001 Heverlee Belgium
| | - Koen Binnemans
- KU Leuven, Department of Chemistry Celestijnenlaan 200F, P.O. box 2404 B-3001 Leuven Belgium
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