Pub Date : 2023-05-26DOI: 10.1080/07366299.2023.2214589
Borhan Pourtalebi, Mohammad Valibeknejad, S. M. Abdoli, A. Akbari
ABSTRACT The current study is a new method for liquid–liquid extraction of copper (II) and zinc that was carried out using an efficient solvent called trifluoroacetylacetone in a hollow fiber membrane contactor (HFMC). To analyze the extraction process and understand its underlying mechanisms, computational fluid dynamics (CFD) was employed. The extraction was performed in three domains by coupling the mass and momentum equation to express the solute transport from the tube side to the shell side through the membrane in a hollow fiber membrane contactor. The finite element approach simulates the governing equation and validates the results. This work aims to obtain the distribution of copper (II) and zinc by performing a simulation. The effect of some crucial parameters was investigated. The results illustrate that the extraction efficiency increases by increasing the partition coefficient and decreasing the flow rate on the tube side. Also, the temperature significantly affects extraction, and by enhancing the temperature from 298 to 313 K, the efficiency increases by 12% for copper (II) and 6.6% for zinc. Furthermore, the membrane porosity was found to be another influential parameter. By increasing the membrane porosity of 25% to 90%, the efficiency increases to 95% for copper (II) and 98% for zinc.
{"title":"CFD Analysis of Simultaneous Removal of Copper (II) and Zinc from Aqueous Solution Using a Hollow Fiber Membrane Contactor","authors":"Borhan Pourtalebi, Mohammad Valibeknejad, S. M. Abdoli, A. Akbari","doi":"10.1080/07366299.2023.2214589","DOIUrl":"https://doi.org/10.1080/07366299.2023.2214589","url":null,"abstract":"ABSTRACT The current study is a new method for liquid–liquid extraction of copper (II) and zinc that was carried out using an efficient solvent called trifluoroacetylacetone in a hollow fiber membrane contactor (HFMC). To analyze the extraction process and understand its underlying mechanisms, computational fluid dynamics (CFD) was employed. The extraction was performed in three domains by coupling the mass and momentum equation to express the solute transport from the tube side to the shell side through the membrane in a hollow fiber membrane contactor. The finite element approach simulates the governing equation and validates the results. This work aims to obtain the distribution of copper (II) and zinc by performing a simulation. The effect of some crucial parameters was investigated. The results illustrate that the extraction efficiency increases by increasing the partition coefficient and decreasing the flow rate on the tube side. Also, the temperature significantly affects extraction, and by enhancing the temperature from 298 to 313 K, the efficiency increases by 12% for copper (II) and 6.6% for zinc. Furthermore, the membrane porosity was found to be another influential parameter. By increasing the membrane porosity of 25% to 90%, the efficiency increases to 95% for copper (II) and 98% for zinc.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42327857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-19DOI: 10.1080/07366299.2023.2214175
E. Konopkina, P. Matveev, A. Kharcheva, Tsagana B. Sumynova, A. Pozdeev, Daniil A. Novichkov, A. Trigub, P. Kalle, A. Kirsanova, S. Kalmykov, V. Petrov, N. Borisova
ABSTRACT In this work, we studied the complex formation (1H, 31P NMR-titration, UV–vis titration, luminescent titration) and solvent extraction of lanthanides with pyridine diphosphonates. The stoichiometry of the complexes was determined: ML and ML2 forms are present. This is confirmed by all of the above methods. It was found that the pyridine ring and P=O groups are involved in the coordination of the metal cation. The coordination environment of the Eu(III) cation was studied more thoroughly using the EXAFS method in solution. Coordination numbers and distances were determined for the complex in solution. The influence of the lanthanide radius on the value of the stability constant was shown. The change in extraction efficiency in the series of lanthanide is described. A new pattern, unusual for other phosphorus-containing ligands, was obtained. To explain the change in the parameters of complexation depending on the system, DFT calculations were carried out. The effect of various initial states of the extracted cations was shown. The initial state with a large amount of nitrates corresponds to a two-phase system during extraction, and with a smaller amount, to a single-phase system with acetonitrile. Additionally, the luminescent properties of the complexes were described in detail as one more applied aspect of the work. . GRAPHICAL ABSTRACT
{"title":"Solvent Extraction and Complexation Studies of Pyridine-di-Phosphonates with Lanthanides(III) in Solutions","authors":"E. Konopkina, P. Matveev, A. Kharcheva, Tsagana B. Sumynova, A. Pozdeev, Daniil A. Novichkov, A. Trigub, P. Kalle, A. Kirsanova, S. Kalmykov, V. Petrov, N. Borisova","doi":"10.1080/07366299.2023.2214175","DOIUrl":"https://doi.org/10.1080/07366299.2023.2214175","url":null,"abstract":"ABSTRACT In this work, we studied the complex formation (1H, 31P NMR-titration, UV–vis titration, luminescent titration) and solvent extraction of lanthanides with pyridine diphosphonates. The stoichiometry of the complexes was determined: ML and ML2 forms are present. This is confirmed by all of the above methods. It was found that the pyridine ring and P=O groups are involved in the coordination of the metal cation. The coordination environment of the Eu(III) cation was studied more thoroughly using the EXAFS method in solution. Coordination numbers and distances were determined for the complex in solution. The influence of the lanthanide radius on the value of the stability constant was shown. The change in extraction efficiency in the series of lanthanide is described. A new pattern, unusual for other phosphorus-containing ligands, was obtained. To explain the change in the parameters of complexation depending on the system, DFT calculations were carried out. The effect of various initial states of the extracted cations was shown. The initial state with a large amount of nitrates corresponds to a two-phase system during extraction, and with a smaller amount, to a single-phase system with acetonitrile. Additionally, the luminescent properties of the complexes were described in detail as one more applied aspect of the work. . GRAPHICAL ABSTRACT","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44170732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-16DOI: 10.1080/07366299.2023.2211631
C. Sharma, R. Patadia, Y. Agrawal
ABSTRACT A novel reagent 2,14-bis[m-nitrophenyl]-calix[4]resorcinarene-8,20-bis[N-phenylbenzo]-dihydroxamic acid (NPC4RADHA) is reported for the liquid-liquid extraction, separation, and simultaneous trace determination of La(III), Ce(III), Nd(III), and Gd(III). The method involves optimizing various parameters such as the concentration of NPC4RADHA, pH, solvent, and extraction time to achieve maximum purity (99.98%) extraction of these rare earths. The stability constant, molar absorptivity, and Beer’s law have been studied. The extracted samples were directly analyzed by ICP-AES, which improves sensitivity with determination limits of 0.020 ng/mL, 0.028 ng/mL, 0.018 ng/mL and 0.025 ng/mL for La, Ce, Nd, and Gd, respectively. The method has been applied to the determination of these elements in monazite sand and standard geological samples. The separation and determination mixture of a Ce(III) and Ce(IV) has been reported.
{"title":"Solvent Extraction, Sequential Separation and Trace Determination of La (III), Ce (III), Nd (III) and Gd (III) with 2, 14-bis[m-nitrophenyl]-Calix[4]Resorcinarene-8, 20-bis[N- phenylbenzo]-dihydroxamic Acid","authors":"C. Sharma, R. Patadia, Y. Agrawal","doi":"10.1080/07366299.2023.2211631","DOIUrl":"https://doi.org/10.1080/07366299.2023.2211631","url":null,"abstract":"ABSTRACT A novel reagent 2,14-bis[m-nitrophenyl]-calix[4]resorcinarene-8,20-bis[N-phenylbenzo]-dihydroxamic acid (NPC4RADHA) is reported for the liquid-liquid extraction, separation, and simultaneous trace determination of La(III), Ce(III), Nd(III), and Gd(III). The method involves optimizing various parameters such as the concentration of NPC4RADHA, pH, solvent, and extraction time to achieve maximum purity (99.98%) extraction of these rare earths. The stability constant, molar absorptivity, and Beer’s law have been studied. The extracted samples were directly analyzed by ICP-AES, which improves sensitivity with determination limits of 0.020 ng/mL, 0.028 ng/mL, 0.018 ng/mL and 0.025 ng/mL for La, Ce, Nd, and Gd, respectively. The method has been applied to the determination of these elements in monazite sand and standard geological samples. The separation and determination mixture of a Ce(III) and Ce(IV) has been reported.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48457751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-15DOI: 10.1080/07366299.2023.2206861
C. Pin, Jean-Luc Piro
ABSTRACT This article describes several extraction chromatographic materials aiming to offer improved potential for isolating trace elements with high charge/ionic radius ratio from accompanying matrix elements in natural samples. Starting with commercially available, field-proven, TRU- and RE-Spec materials (Eichrom Technologies), three resins containing less TBP in the CMPO-TBP mixtures, or even neat CMPO only, have been prepared and characterized through measurement of the distribution ratios of some fifty elements in HNO3 and HCl media of variable strength. These resins were further evaluated for analytical applications on geochemical samples. The results highlight a strong enhancement of weight distribution ratios of many elements of interest in geochemistry, cosmochemistry, and environmental sciences (Lanthanides, naturally occurring Actinides, High Field Strength Elements). Combined with good chromatographic characteristics, these high Dw’s make it possible to achieve excellent group separations by using very small columns operated at relatively high, gravity-driven flow rate. Moreover, in an attempt to further improve the selectivity against Fe(III) and Ti(IV), preliminary investigations were made on an additional pair of resin prototypes impregnated with a CMPO-substituted calixarene. Although promising distribution ratio data were obtained, these prototypes did not permit to prepare columns with satisfactory chromatographic characteristics, and this approach still waits for a better impregnation methodof the porous inert support.
{"title":"Characterization of a Set of Improved, CMPO-Based, Extraction Chromatographic Resins: Applications to the Separation of Elements Important for Geochemical and Environmental Studies","authors":"C. Pin, Jean-Luc Piro","doi":"10.1080/07366299.2023.2206861","DOIUrl":"https://doi.org/10.1080/07366299.2023.2206861","url":null,"abstract":"ABSTRACT This article describes several extraction chromatographic materials aiming to offer improved potential for isolating trace elements with high charge/ionic radius ratio from accompanying matrix elements in natural samples. Starting with commercially available, field-proven, TRU- and RE-Spec materials (Eichrom Technologies), three resins containing less TBP in the CMPO-TBP mixtures, or even neat CMPO only, have been prepared and characterized through measurement of the distribution ratios of some fifty elements in HNO3 and HCl media of variable strength. These resins were further evaluated for analytical applications on geochemical samples. The results highlight a strong enhancement of weight distribution ratios of many elements of interest in geochemistry, cosmochemistry, and environmental sciences (Lanthanides, naturally occurring Actinides, High Field Strength Elements). Combined with good chromatographic characteristics, these high Dw’s make it possible to achieve excellent group separations by using very small columns operated at relatively high, gravity-driven flow rate. Moreover, in an attempt to further improve the selectivity against Fe(III) and Ti(IV), preliminary investigations were made on an additional pair of resin prototypes impregnated with a CMPO-substituted calixarene. Although promising distribution ratio data were obtained, these prototypes did not permit to prepare columns with satisfactory chromatographic characteristics, and this approach still waits for a better impregnation methodof the porous inert support.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42060949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-11DOI: 10.1080/07366299.2023.2206440
Stijn Raiguel, Viet Tu Nguyen, Isadora Reis Rodrigues, Clio Deferm, S. Riaño, K. Binnemans
ABSTRACT The world's seas and oceans contain vast amounts of lithium, but the low concentration hereof renders solvent extraction impractical for its recovery. By contrast, seawater desalination brine, after treatment by nanofiltration, contains a roughly tenfold greater concentration of lithium than raw seawater. Hence, lithium can be effectively recovered from such streams using solvent extaction. Compared with other techniques to sequester lithium from dilute solutions, solvent extraction offers the advantages of simple operations, robust and well-established technology and high recovery yields. Thus, we propose a solvent-extraction based process to recover lithium from seawater desalination brine, treated by nanofiltration. The first step comprises the removal of magnesium and calcium using methyltrioctylammonium neodecanoate in p-cymene. This is followed by a lithium extraction step using the extractants Mextral 54–100 and Cyanex 923 in Shellsol D70 diluent. The lithium extract is then scrubbed with water and stripped with hydrochloric acid. Subsequently, residual alkaline earth metals are removed with sodium hydroxide in ethanol and finally lithium is precipitated using sodium carbonate. The solvent extraction, scrubbing and stripping steps were demonstrated on mini-pilot scale in continuous countercurrent mode (in mixer-settlers), while the precipitation steps were demonstrated in batch. The process was found to have an overall yield of 74%, affording a lithium carbonate product with a purity of 97 wt%.
{"title":"Recovery of Lithium from Simulated Nanofiltration-Treated Seawater Desalination Brine Using Solvent Extraction and Selective Precipitation","authors":"Stijn Raiguel, Viet Tu Nguyen, Isadora Reis Rodrigues, Clio Deferm, S. Riaño, K. Binnemans","doi":"10.1080/07366299.2023.2206440","DOIUrl":"https://doi.org/10.1080/07366299.2023.2206440","url":null,"abstract":"ABSTRACT The world's seas and oceans contain vast amounts of lithium, but the low concentration hereof renders solvent extraction impractical for its recovery. By contrast, seawater desalination brine, after treatment by nanofiltration, contains a roughly tenfold greater concentration of lithium than raw seawater. Hence, lithium can be effectively recovered from such streams using solvent extaction. Compared with other techniques to sequester lithium from dilute solutions, solvent extraction offers the advantages of simple operations, robust and well-established technology and high recovery yields. Thus, we propose a solvent-extraction based process to recover lithium from seawater desalination brine, treated by nanofiltration. The first step comprises the removal of magnesium and calcium using methyltrioctylammonium neodecanoate in p-cymene. This is followed by a lithium extraction step using the extractants Mextral 54–100 and Cyanex 923 in Shellsol D70 diluent. The lithium extract is then scrubbed with water and stripped with hydrochloric acid. Subsequently, residual alkaline earth metals are removed with sodium hydroxide in ethanol and finally lithium is precipitated using sodium carbonate. The solvent extraction, scrubbing and stripping steps were demonstrated on mini-pilot scale in continuous countercurrent mode (in mixer-settlers), while the precipitation steps were demonstrated in batch. The process was found to have an overall yield of 74%, affording a lithium carbonate product with a purity of 97 wt%.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42517617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-08DOI: 10.1080/07366299.2023.2205440
A. Westesen, E. Campbell, R. Peterson
ABSTRACT Crystalline silicotitanate (CST) ion exchanger is currently used to remove cesium (137Cs) from the aqueous phase of Hanford tank wastes in preparation for vitrification at the Waste Treatment and Immobilization Plant (WTP). The CST is a non-elutable inorganic ion exchanger targeted to maintain a decontamination factor of ≥1,000 prior to the column effluent reaching a waste acceptance criterion. In an effort to reduce costs generated by ion exchange processing, system optimization of the waste treatment has been conducted. Decreasing the tank waste supernate sodium molarity prior to processing through the ion exchange columns showed that it can significantly reduce the number of columns used while maintaining the necessary sodium throughput. Optimization of this process can result in significant cost savings and ultimately result in less waste production.
{"title":"Optimization of Cesium Ion Exchange Performance with Hanford Tank Waste Feed Dilution","authors":"A. Westesen, E. Campbell, R. Peterson","doi":"10.1080/07366299.2023.2205440","DOIUrl":"https://doi.org/10.1080/07366299.2023.2205440","url":null,"abstract":"ABSTRACT Crystalline silicotitanate (CST) ion exchanger is currently used to remove cesium (137Cs) from the aqueous phase of Hanford tank wastes in preparation for vitrification at the Waste Treatment and Immobilization Plant (WTP). The CST is a non-elutable inorganic ion exchanger targeted to maintain a decontamination factor of ≥1,000 prior to the column effluent reaching a waste acceptance criterion. In an effort to reduce costs generated by ion exchange processing, system optimization of the waste treatment has been conducted. Decreasing the tank waste supernate sodium molarity prior to processing through the ion exchange columns showed that it can significantly reduce the number of columns used while maintaining the necessary sodium throughput. Optimization of this process can result in significant cost savings and ultimately result in less waste production.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41734394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-08DOI: 10.1080/07366299.2023.2197969
A. Wilson, R. A. Grant, Ross J. Gordon, J. Love, C. Morrison, Kirstian J. Macruary, G. Nichol, P. Tasker
ABSTRACT New thioetheramide ligands (L, PhS(CH2)nCONRR’) co-extract Pd(II) and Pt(IV) from acidic chloride solutions. The Pd is transferred to a water-immiscible phase as a [Pd(L)2Cl2] complex with thioether groups in the inner sphere whilst Pt is extracted in an outer-sphere assembly, [(LH)2·PtCl6], containing protonated reagent molecules LH+ that charge-balance the chloridoplatinate dianion, [PtCl6]2-. The much higher kinetic and thermodynamic stability of the Pd(II) complex makes it possible to strip the Pt into a weakly acidic aqueous phase before recovering the Pd by back-extraction into aqueous ammonia to form [Pd(NH3)4]Cl2, thereby separating the two elements. An alkyl spacer group with two methylene units between the thioether (S) and amide (C) atoms is a stronger extractant for both metals than those with one or three methylene units. The extractants reject trianionic chloridometalates with higher hydration energies such as [IrCl6]3-. X-ray structures of two [Pd(L)2Cl2] complexes (L, PhSCH2CONH-n-C4H9 or PhS(CH2)2CONH-n-C4H9) have planar coordination with a transarrangement of the thioether groups and geometries very similar to those predicted by DFT calculations. These calculations show that addition of a proton to the proligands L generates a pseudochelate with the added H+ located between the S atom and the carbonyl O atom. In contrast to related ether- and amino-amide extractants, this pseudochelate ring is broken in the [(LH)2.PtCl6] assemblies formed by the thioetheramides and the OH+ and NH units make the close contacts to the PtCl6 2- ion.
{"title":"Ditopic Extractants to Separate Palladium(II) and Platinum(IV) Chloridometalates via Inner or Outer Sphere Binding","authors":"A. Wilson, R. A. Grant, Ross J. Gordon, J. Love, C. Morrison, Kirstian J. Macruary, G. Nichol, P. Tasker","doi":"10.1080/07366299.2023.2197969","DOIUrl":"https://doi.org/10.1080/07366299.2023.2197969","url":null,"abstract":"ABSTRACT New thioetheramide ligands (L, PhS(CH2)nCONRR’) co-extract Pd(II) and Pt(IV) from acidic chloride solutions. The Pd is transferred to a water-immiscible phase as a [Pd(L)2Cl2] complex with thioether groups in the inner sphere whilst Pt is extracted in an outer-sphere assembly, [(LH)2·PtCl6], containing protonated reagent molecules LH+ that charge-balance the chloridoplatinate dianion, [PtCl6]2-. The much higher kinetic and thermodynamic stability of the Pd(II) complex makes it possible to strip the Pt into a weakly acidic aqueous phase before recovering the Pd by back-extraction into aqueous ammonia to form [Pd(NH3)4]Cl2, thereby separating the two elements. An alkyl spacer group with two methylene units between the thioether (S) and amide (C) atoms is a stronger extractant for both metals than those with one or three methylene units. The extractants reject trianionic chloridometalates with higher hydration energies such as [IrCl6]3-. X-ray structures of two [Pd(L)2Cl2] complexes (L, PhSCH2CONH-n-C4H9 or PhS(CH2)2CONH-n-C4H9) have planar coordination with a transarrangement of the thioether groups and geometries very similar to those predicted by DFT calculations. These calculations show that addition of a proton to the proligands L generates a pseudochelate with the added H+ located between the S atom and the carbonyl O atom. In contrast to related ether- and amino-amide extractants, this pseudochelate ring is broken in the [(LH)2.PtCl6] assemblies formed by the thioetheramides and the OH+ and NH units make the close contacts to the PtCl6 2- ion.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48977287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-26DOI: 10.1080/07366299.2023.2202224
Christian G. Bustillos, Randy Ngelale, Mikael G. Nilsson
ABSTRACT Organic solutions comprising the Actinide Lanthanide Separation Process (ALSEP) solvent consisting of 0.5 M 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) and 0.05 M N,N,N’,N’-tetra(2-ethylhexyl)diglycolamide (T2EHDGA) in n-dodecane were subjected to low LET and high LET irradiation before and after equilibration with an aqueous phase of 3 M HNO3. Degradation dose constants revealed greater ligand degradation due to gamma irradiation than alpha irradiation for both ligands. Furthermore, equilibration with nitric acid did not have a significant impact on ligand degradation for either irradiation source. Identified degradation products were similar for both gamma and alpha irradiation and occurred mostly through the rupture of the N–Ccarbonyl and C–Oether bonds for T2EHDGA and the C–Oether bond in HEH[EHP]. Acid contact appears to alter the degradation pathway by favoring the formation of higher molecular weight recombination products. Mixed T2EHDGA-HEH[EHP]-NO3 complexes were formed with Nd(III) after extraction from 3 M HNO3, and low LET gamma irradiation of the Nd(III) loaded organic solution produced similar degradation products as the organic solution absent of Nd(III). Interestingly, and likely due to the greater radiolytic susceptibility of T2EHDGA than HEH[EHP], a HEH[EHP]-Nd(III) complex appears to form as the T2EHDGA degrades with increasing absorbed dose.
摘要包含锕系元素-镧系元素分离工艺（ALSEP）溶剂的有机溶液，该溶剂由0.5 M-2-乙基己基膦酸单-2-乙基己基酯（HEH[EHP]）和0.05 在用3 M HNO3。降解剂量常数显示，对于两种配体，由于γ辐射而导致的配体降解大于α辐射。此外，用硝酸平衡对两种辐射源的配体降解都没有显著影响。已鉴定的降解产物在γ和α辐照下相似，主要通过T2EHDGA的N–C羰基和C–Oether键以及HEH[EHP]的C–Oether键断裂发生。酸接触似乎通过有利于形成更高分子量的重组产物来改变降解途径。Nd（III）从3 M HNO3和负载Nd（III）的有机溶液的低LET伽马辐射产生与不存在Nd（Ⅲ）的有机溶剂类似的降解产物。有趣的是，很可能是由于T2EHDGA比HEH[EHP]更大的放射分解敏感性，随着T2EHDGA随着吸收剂量的增加而降解，似乎形成了HEH[EHP]-Nd（III）复合物。
{"title":"Low and High LET Degradation Studies of Metal-Loaded Organic Phase Ligands in the ALSEP Process","authors":"Christian G. Bustillos, Randy Ngelale, Mikael G. Nilsson","doi":"10.1080/07366299.2023.2202224","DOIUrl":"https://doi.org/10.1080/07366299.2023.2202224","url":null,"abstract":"ABSTRACT Organic solutions comprising the Actinide Lanthanide Separation Process (ALSEP) solvent consisting of 0.5 M 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) and 0.05 M N,N,N’,N’-tetra(2-ethylhexyl)diglycolamide (T2EHDGA) in n-dodecane were subjected to low LET and high LET irradiation before and after equilibration with an aqueous phase of 3 M HNO3. Degradation dose constants revealed greater ligand degradation due to gamma irradiation than alpha irradiation for both ligands. Furthermore, equilibration with nitric acid did not have a significant impact on ligand degradation for either irradiation source. Identified degradation products were similar for both gamma and alpha irradiation and occurred mostly through the rupture of the N–Ccarbonyl and C–Oether bonds for T2EHDGA and the C–Oether bond in HEH[EHP]. Acid contact appears to alter the degradation pathway by favoring the formation of higher molecular weight recombination products. Mixed T2EHDGA-HEH[EHP]-NO3 complexes were formed with Nd(III) after extraction from 3 M HNO3, and low LET gamma irradiation of the Nd(III) loaded organic solution produced similar degradation products as the organic solution absent of Nd(III). Interestingly, and likely due to the greater radiolytic susceptibility of T2EHDGA than HEH[EHP], a HEH[EHP]-Nd(III) complex appears to form as the T2EHDGA degrades with increasing absorbed dose.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41958172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-10DOI: 10.1080/07366299.2023.2197016
I. Fleitlikh, N. Grigorieva, A. Tikhonov, V. Krasnov, Elena Karpova, O. Logutenko
ABSTRACT In this work, solvent extraction of In(III) from sulfate solutions by using mixtures of D2EHPA with octyl alcohol and octanoic acid was investigated. The introduction of the additives into the organic phase was shown to lead to an antagonistic effect thus facilitating efficient indium stripping from the loaded organic phase. The antagonistic effect is significantly higher in the D2EHPA (HR) and octyl alcohol (HA) mixtures. The formation of stable associates between D2EHPA and HA leads to a decrease in the extraction efficiency of indium. In the presence of alcohol, almost complete stripping of indium from a D2EHPA loaded phase can be achieved to produce a strip liquor containing>33.0 g/L In. Based on the analysis of the extraction data and by using nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy of the organic phases, it was concluded that indium extraction with D2EHPA in octyl alcohol is due to the formation of the extracted compound InR3. The equilibrium constant (logK) for indium extraction with solutions of D2EHPA in octyl alcohol was found to be − 0.12 ± 0.05. Extraction systems containing D2EHPA and octyl alcohol can be used to recover indium from various industrial solutions, in particular from the solutions derived from lead-zinc production and from liquid crystal display panel wastes.
{"title":"Indium Extraction from Sulfate Solutions with a Mixture of Di(2-Ethylhexyl)Phosphoric Acid and Octyl Alcohol","authors":"I. Fleitlikh, N. Grigorieva, A. Tikhonov, V. Krasnov, Elena Karpova, O. Logutenko","doi":"10.1080/07366299.2023.2197016","DOIUrl":"https://doi.org/10.1080/07366299.2023.2197016","url":null,"abstract":"ABSTRACT In this work, solvent extraction of In(III) from sulfate solutions by using mixtures of D2EHPA with octyl alcohol and octanoic acid was investigated. The introduction of the additives into the organic phase was shown to lead to an antagonistic effect thus facilitating efficient indium stripping from the loaded organic phase. The antagonistic effect is significantly higher in the D2EHPA (HR) and octyl alcohol (HA) mixtures. The formation of stable associates between D2EHPA and HA leads to a decrease in the extraction efficiency of indium. In the presence of alcohol, almost complete stripping of indium from a D2EHPA loaded phase can be achieved to produce a strip liquor containing>33.0 g/L In. Based on the analysis of the extraction data and by using nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy of the organic phases, it was concluded that indium extraction with D2EHPA in octyl alcohol is due to the formation of the extracted compound InR3. The equilibrium constant (logK) for indium extraction with solutions of D2EHPA in octyl alcohol was found to be − 0.12 ± 0.05. Extraction systems containing D2EHPA and octyl alcohol can be used to recover indium from various industrial solutions, in particular from the solutions derived from lead-zinc production and from liquid crystal display panel wastes.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45553616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-09DOI: 10.1080/07366299.2023.2187700
S. Bondareva, Y. Murinov
ABSTRACT The solvent extraction of erbium(III), representing heavy lanthanides, from nitrate solutions has been studied using a novel mixture of neodecanoic acid (HA) with 1-(2-neononylamidoethyl)-2-neononyl-2-imidazoline (L) in toluene with 15 % (v/v) of n-decanol. The synergistic extraction of erbium(III) has been found in the equilibrium pH range from 6.0 to 6.5. The effects of the equilibration time, the temperature, the nature of diluent, the aqueous phase acidity, and variation of one extractant at a fixed concentration of the other extractant have been investigated. The temperature had no effect on the extraction process in the range of 0–45°C. FT-IR spectra of the mixed extractant before and after extraction of erbium were examined, and the loading capacity of the mixed extractant for Er(III) was determined. The experimental data indicated that the erbium ion is not directly coordinated by L, and the nitrate ions are not involved in the extraction of erbium(III). In the equilibrium pH range between 5.0 and 6.0, the extracted species were determined to be [Er(OH)A2·L] by the slope analysis method. The increase in the pH leads to the dominance of [Er(OH)2A·L] as the main extracted species. The extraction mechanism is discussed. The Nd/Pr, Y/Pr, Dy/Y, Ho/Y, and Er/Y separation factors were calculated, and the possibility of the separation of the Er–Y pair was demonstrated.
{"title":"Synergistic Solvent Extraction of Erbium(III) using a Mixture of Neodecanoic Acid with 1-(2-Neononylamidoethyl)-2-Neononyl-2-Imidazoline","authors":"S. Bondareva, Y. Murinov","doi":"10.1080/07366299.2023.2187700","DOIUrl":"https://doi.org/10.1080/07366299.2023.2187700","url":null,"abstract":"ABSTRACT The solvent extraction of erbium(III), representing heavy lanthanides, from nitrate solutions has been studied using a novel mixture of neodecanoic acid (HA) with 1-(2-neononylamidoethyl)-2-neononyl-2-imidazoline (L) in toluene with 15 % (v/v) of n-decanol. The synergistic extraction of erbium(III) has been found in the equilibrium pH range from 6.0 to 6.5. The effects of the equilibration time, the temperature, the nature of diluent, the aqueous phase acidity, and variation of one extractant at a fixed concentration of the other extractant have been investigated. The temperature had no effect on the extraction process in the range of 0–45°C. FT-IR spectra of the mixed extractant before and after extraction of erbium were examined, and the loading capacity of the mixed extractant for Er(III) was determined. The experimental data indicated that the erbium ion is not directly coordinated by L, and the nitrate ions are not involved in the extraction of erbium(III). In the equilibrium pH range between 5.0 and 6.0, the extracted species were determined to be [Er(OH)A2·L] by the slope analysis method. The increase in the pH leads to the dominance of [Er(OH)2A·L] as the main extracted species. The extraction mechanism is discussed. The Nd/Pr, Y/Pr, Dy/Y, Ho/Y, and Er/Y separation factors were calculated, and the possibility of the separation of the Er–Y pair was demonstrated.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41846128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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