Pub Date : 2023-01-06DOI: 10.1080/07366299.2022.2160646
Marilú Pérez García, Andrés García Alejo, N. D. De Silva, Yichen Liu, T. Windus
ABSTRACT Stability constants provide insight into ion complexation in water. While computational studies have been shown to model the energy of the complexation successfully using a thermodynamic cycle approach, it does not extend to calculating the stability constants for 1:1 lanthanide to ligand complexes in solution. Using B3LYP and 6-31+G* Pople basis with small core effective core potential (ECP) on the lanthanum ion, and a solvent model based on the full solute electron density (SMD) solvation model we computed and compared with previously published stability constants of the ligands: acetate, acetohydroximate, acetylacetonate, methanoate, tropolonate, hydroxide, catecholate, malonate, oxalate, phthalate, and sulfate. The best R2 values for the thermodynamic cycle can only be determined by separating the mono and divalent ions to achieve an R2 value of 0.86 and 0.74 for mono and divalent ions, respectively. We show that by optimizing the lanthanide-ligand structures in implicit solvent, we achieve an improved correlation between experimental and computed stability constants of R2 value of 0.89 for the combined mono and divalent ions.
{"title":"Solvent Phase Optimizations Improve Correlations with Experimental Stability Constants for Aqueous Lanthanide Complexes","authors":"Marilú Pérez García, Andrés García Alejo, N. D. De Silva, Yichen Liu, T. Windus","doi":"10.1080/07366299.2022.2160646","DOIUrl":"https://doi.org/10.1080/07366299.2022.2160646","url":null,"abstract":"ABSTRACT Stability constants provide insight into ion complexation in water. While computational studies have been shown to model the energy of the complexation successfully using a thermodynamic cycle approach, it does not extend to calculating the stability constants for 1:1 lanthanide to ligand complexes in solution. Using B3LYP and 6-31+G* Pople basis with small core effective core potential (ECP) on the lanthanum ion, and a solvent model based on the full solute electron density (SMD) solvation model we computed and compared with previously published stability constants of the ligands: acetate, acetohydroximate, acetylacetonate, methanoate, tropolonate, hydroxide, catecholate, malonate, oxalate, phthalate, and sulfate. The best R2 values for the thermodynamic cycle can only be determined by separating the mono and divalent ions to achieve an R2 value of 0.86 and 0.74 for mono and divalent ions, respectively. We show that by optimizing the lanthanide-ligand structures in implicit solvent, we achieve an improved correlation between experimental and computed stability constants of R2 value of 0.89 for the combined mono and divalent ions.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"241 - 251"},"PeriodicalIF":2.0,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44397470","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 : 2022-11-23DOI: 10.1080/07366299.2022.2136488
M. Carrott, C. Maher, C. Mason, M. Sarsfield, D. Whittaker, R. J. Taylor
ABSTRACT EURO-GANEX is an innovative hydrometallurgical process for the group separation of transuranic actinides from future spent nuclear fuels. A flowsheet test of a process upset (or ‘maloperation’) has been carried out involving the reduction in the concentration of the scrub acid feed to the extract-scrub contactors. The experimental test was completed in two stages. First, the extract-scrub contactors were run under normal flowsheet conditions before initiating the process upset by reducing the scrub acidity from 0.5 to 0.05 mol/L HNO3. At low acidity, a change in the online UV-Vis spectra of the solvent phase indicated the formation of hydrolyzed plutonium species or plutonium colloid formation. Surprisingly, however, this did not lead to the recycle and accumulation of plutonium in the extract-scrub contactors as expected indicating that the EURO-GANEX process is quite robust towards this process upset. Further spectroscopic investigations of the organic-phase species were also performed to characterize the conditions under which the hydrolyzed plutonium species form in the EURO-GANEX solvent as well as separate TODGA and DMDOHEMA phases. The spectroscopic studies supported the view that Pu(IV) hydrolyses at low acidity but the hydrolysis is limited by the organic ligands and is consequently reversible on raising the acidity again. The hydrolysis was also observed in separate TODGA and DMDOHEMA phases.
{"title":"Experimental Test of a Process Upset in the EURO-GANEX Process and Spectroscopic Study of the Product","authors":"M. Carrott, C. Maher, C. Mason, M. Sarsfield, D. Whittaker, R. J. Taylor","doi":"10.1080/07366299.2022.2136488","DOIUrl":"https://doi.org/10.1080/07366299.2022.2136488","url":null,"abstract":"ABSTRACT EURO-GANEX is an innovative hydrometallurgical process for the group separation of transuranic actinides from future spent nuclear fuels. A flowsheet test of a process upset (or ‘maloperation’) has been carried out involving the reduction in the concentration of the scrub acid feed to the extract-scrub contactors. The experimental test was completed in two stages. First, the extract-scrub contactors were run under normal flowsheet conditions before initiating the process upset by reducing the scrub acidity from 0.5 to 0.05 mol/L HNO3. At low acidity, a change in the online UV-Vis spectra of the solvent phase indicated the formation of hydrolyzed plutonium species or plutonium colloid formation. Surprisingly, however, this did not lead to the recycle and accumulation of plutonium in the extract-scrub contactors as expected indicating that the EURO-GANEX process is quite robust towards this process upset. Further spectroscopic investigations of the organic-phase species were also performed to characterize the conditions under which the hydrolyzed plutonium species form in the EURO-GANEX solvent as well as separate TODGA and DMDOHEMA phases. The spectroscopic studies supported the view that Pu(IV) hydrolyses at low acidity but the hydrolysis is limited by the organic ligands and is consequently reversible on raising the acidity again. The hydrolysis was also observed in separate TODGA and DMDOHEMA phases.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"88 - 117"},"PeriodicalIF":2.0,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43219616","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 : 2022-10-03DOI: 10.1080/07366299.2022.2125151
B. Verlinden, A. Wilden, K. Van Hecke, Richard J. M. Egberink, J. Huskens, W. Verboom, Michelle Hupert, P. Weßling, A. Geist, P. Panak, R. Hermans, M. Verwerft, G. Modolo, K. Binnemans, T. Cardinaels
ABSTRACT The diglycolamide 2,2’-oxybis(N,N-di-n-decylpropanamide) (mTDDGA) is being studied as an extractant for actinides and lanthanides in the European Grouped Actinide Extraction (EURO-GANEX) process. The aim is the development of a more simplified process using a single extractant instead of a mixture of extractants used in the current EURO-GANEX process. This work presents solvent optimization studies of mTDDGA, with regards to the extraction characteristics of the different diastereomers of mTDGA and of mixed diastereomer solutions. Also radiolysis behavior has been studied by irradiation of solvent extraction systems in a gamma irradiation facility using 60Co. The availability of irradiated organic solutions made it possible to gain valuable insights into the plutonium loading capacity after gamma-irradiation of the solvent up to 445 kGy and to quantify degradation compounds. Solvent extraction characteristic of the major degradation compounds themselves were determined. Like other methylated diglycolamides, we found a remarkable difference in extraction of up to two orders of magnitude between the two diastereomers. High plutonium loading (36 g L−1) is feasible using this single extractant, even after absorbing a dose of 445 kGy. This remarkable observation is possibly promoted by the presence of the main degradation compound which extracts plutonium verywell.
摘要在欧洲组分锕系元素萃取（EURO-GANEX）工艺中，研究了2,2'-氧基双（N，N-二正-癸基丙酰胺）二甘醇酰胺（mTDDGA）作为锕系和镧系元素的萃取剂。目的是开发一种更简单的工艺，使用单一的萃取剂，而不是目前EURO-GANEX工艺中使用的萃取剂混合物。本工作介绍了mTDGA的溶剂优化研究，涉及mTDGA不同非对映异构体和混合非对映体溶液的提取特性。此外，还通过在使用60Co的伽马辐照设备中对溶剂萃取系统进行辐照来研究辐解行为。辐照有机溶液的可用性使得有可能对高达445kGy的溶剂的伽马辐照后的钚负载能力获得有价值的见解，并量化降解化合物。测定了主要降解化合物本身的溶剂萃取特性。与其他甲基化二甘醇酰胺一样，我们发现两种非对映体在提取方面存在高达两个数量级的显著差异。钚装载量高（36 g L−1）使用这种单一提取剂是可行的，即使在吸收445kGy的剂量后也是如此。这种显著的观察结果可能是由于主要降解化合物的存在而促进的，该化合物能很好地提取钚。
{"title":"Solvent Optimization Studies for a New EURO-GANEX Process with 2,2’-Oxybis(N,N-di-n-decylpropanamide) (mTDDGA) and Its Radiolysis Products","authors":"B. Verlinden, A. Wilden, K. Van Hecke, Richard J. M. Egberink, J. Huskens, W. Verboom, Michelle Hupert, P. Weßling, A. Geist, P. Panak, R. Hermans, M. Verwerft, G. Modolo, K. Binnemans, T. Cardinaels","doi":"10.1080/07366299.2022.2125151","DOIUrl":"https://doi.org/10.1080/07366299.2022.2125151","url":null,"abstract":"ABSTRACT The diglycolamide 2,2’-oxybis(N,N-di-n-decylpropanamide) (mTDDGA) is being studied as an extractant for actinides and lanthanides in the European Grouped Actinide Extraction (EURO-GANEX) process. The aim is the development of a more simplified process using a single extractant instead of a mixture of extractants used in the current EURO-GANEX process. This work presents solvent optimization studies of mTDDGA, with regards to the extraction characteristics of the different diastereomers of mTDGA and of mixed diastereomer solutions. Also radiolysis behavior has been studied by irradiation of solvent extraction systems in a gamma irradiation facility using 60Co. The availability of irradiated organic solutions made it possible to gain valuable insights into the plutonium loading capacity after gamma-irradiation of the solvent up to 445 kGy and to quantify degradation compounds. Solvent extraction characteristic of the major degradation compounds themselves were determined. Like other methylated diglycolamides, we found a remarkable difference in extraction of up to two orders of magnitude between the two diastereomers. High plutonium loading (36 g L−1) is feasible using this single extractant, even after absorbing a dose of 445 kGy. This remarkable observation is possibly promoted by the presence of the main degradation compound which extracts plutonium verywell.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"59 - 87"},"PeriodicalIF":2.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42520195","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 : 2022-09-19DOI: 10.1080/07366299.2022.2120770
Yuehua Wu, J. Vovers, H. T. Lu, Wen Li, Geoffrey W. Stevens, K. Mumford
ABSTRACT Solvent extraction plays a vital role in manufacturing high purity alkaloids from natural poppies. Cyanex® 923, which has been widely used in hydrometallurgical processes, is shown to be an effective extractant for natural alkaloid extraction. In this work, 0.2 M Cyanex® 923 in xylene (dispersed phase) was used to investigate the equilibrium isotherm of morphine at pH 9 and morphine extraction in two different reciprocating Karr columns. Two sources of morphine solution (continuous phase), including technical morphine with few impurities and industrial upstream morphine rich extract containing more impurities and other alkaloids, were studied to investigate morphine mass transfer efficiencies in the Karr columns based on different dispersed phase velocities and reciprocating frequencies. The mass transfer coefficients of technical morphine solution were calculated using a backflow model associated with axial dispersion, and the mass transfer coefficients were further used to regress a mass transfer correlation. The regressed correlation was further validated, and the process model was shown to be reliable to predict the extraction efficiency, and outlet morphine concentration of both aqueous phase and organic phase. This work provides insights to scale-up the process design in a short time, bridging the gap between bench scale research and pilot industry scale testing using a simple correlation method.
溶剂萃取法在从天然罂粟中提取高纯度生物碱中起着至关重要的作用。Cyanex®923已广泛应用于湿法冶金工艺，是一种有效的天然生物碱提取剂。在这项工作中，0.2 M Cyanex®923在二甲苯(分散相)中用于研究吗啡在pH值为9时的平衡等温线和吗啡在两种不同的循环Karr柱上的提取。研究了两种来源的吗啡溶液(连续相)，包括杂质较少的技术吗啡和含有较多杂质和其他生物碱的工业上游富吗啡提取物，基于不同的分散相速度和往复频率，研究了吗啡在Karr柱中的传质效率。采用与轴向弥散相关的回流模型计算技术吗啡溶液的传质系数，并利用传质系数回归传质相关性。进一步验证了回归相关性，结果表明，该过程模型能够较好地预测提取效率以及水相和有机相出口吗啡浓度。这项工作为在短时间内扩大工艺设计提供了见解，利用简单的相关方法弥合了实验规模研究和试点工业规模测试之间的差距。
{"title":"Investigation of the Extraction of Natural Alkaloids in Karr Reciprocating Plate Columns: Mass Transfer Study","authors":"Yuehua Wu, J. Vovers, H. T. Lu, Wen Li, Geoffrey W. Stevens, K. Mumford","doi":"10.1080/07366299.2022.2120770","DOIUrl":"https://doi.org/10.1080/07366299.2022.2120770","url":null,"abstract":"ABSTRACT Solvent extraction plays a vital role in manufacturing high purity alkaloids from natural poppies. Cyanex® 923, which has been widely used in hydrometallurgical processes, is shown to be an effective extractant for natural alkaloid extraction. In this work, 0.2 M Cyanex® 923 in xylene (dispersed phase) was used to investigate the equilibrium isotherm of morphine at pH 9 and morphine extraction in two different reciprocating Karr columns. Two sources of morphine solution (continuous phase), including technical morphine with few impurities and industrial upstream morphine rich extract containing more impurities and other alkaloids, were studied to investigate morphine mass transfer efficiencies in the Karr columns based on different dispersed phase velocities and reciprocating frequencies. The mass transfer coefficients of technical morphine solution were calculated using a backflow model associated with axial dispersion, and the mass transfer coefficients were further used to regress a mass transfer correlation. The regressed correlation was further validated, and the process model was shown to be reliable to predict the extraction efficiency, and outlet morphine concentration of both aqueous phase and organic phase. This work provides insights to scale-up the process design in a short time, bridging the gap between bench scale research and pilot industry scale testing using a simple correlation method.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"36 - 58"},"PeriodicalIF":2.0,"publicationDate":"2022-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46591946","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 : 2022-09-07DOI: 10.1080/07366299.2022.2110686
I. Smirnov, M. Karavan, E. Kenf, L. Tkachenko, V. V. Timoshenko, A. Brechalov, T. Maltseva, Y. Ermolenko
ABSTRACT The extraction of cesium, strontium, and a number of stable components of simulated high-level waste solutions from nitric acid media with solutions of crown ether derivatives in new fluorinated diluents was studied. Based on the data on the solubility of the extractants into the aqueous phase and the physicochemical properties of the diluents used, the most promising extraction systems were chosen: crown ethers 4,4‘(5’)-di-tert-butyldibenzo-18-crown-6 (L1) and 4,4‘(5’)-di-tert-butyldicyclohexyl-18-crown-6 (L2) in bis(2,2,3,3-tetrafluoropropyl) carbonate (BK-1) and bis(2,2,3,3-tetrafluoropropoxy)methane (FN-1). For these systems, the extraction of a number of stable components and their subsequent stripping with water and solutions of chelating agents were studied. Lead was found to be co-extracted to the greatest extent. To a lesser extent, barium and calcium cations are co-extracted with strontium, and rubidium and potassium cations with cesium. Lead, barium, and silver are the most difficult to strip; however, the problem of lead stripping can be solved by using DTPA or citric acid solutions neutralized with ammonia to weakly alkaline (pH 8) media.
{"title":"Extraction of Cesium, Strontium, and Stable Simulated HLW Components with Substituted Crown Ethers in New Fluorinated Diluents","authors":"I. Smirnov, M. Karavan, E. Kenf, L. Tkachenko, V. V. Timoshenko, A. Brechalov, T. Maltseva, Y. Ermolenko","doi":"10.1080/07366299.2022.2110686","DOIUrl":"https://doi.org/10.1080/07366299.2022.2110686","url":null,"abstract":"ABSTRACT The extraction of cesium, strontium, and a number of stable components of simulated high-level waste solutions from nitric acid media with solutions of crown ether derivatives in new fluorinated diluents was studied. Based on the data on the solubility of the extractants into the aqueous phase and the physicochemical properties of the diluents used, the most promising extraction systems were chosen: crown ethers 4,4‘(5’)-di-tert-butyldibenzo-18-crown-6 (L1) and 4,4‘(5’)-di-tert-butyldicyclohexyl-18-crown-6 (L2) in bis(2,2,3,3-tetrafluoropropyl) carbonate (BK-1) and bis(2,2,3,3-tetrafluoropropoxy)methane (FN-1). For these systems, the extraction of a number of stable components and their subsequent stripping with water and solutions of chelating agents were studied. Lead was found to be co-extracted to the greatest extent. To a lesser extent, barium and calcium cations are co-extracted with strontium, and rubidium and potassium cations with cesium. Lead, barium, and silver are the most difficult to strip; however, the problem of lead stripping can be solved by using DTPA or citric acid solutions neutralized with ammonia to weakly alkaline (pH 8) media.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"40 1","pages":"756 - 776"},"PeriodicalIF":2.0,"publicationDate":"2022-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59691399","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 : 2022-09-05DOI: 10.1080/07366299.2022.2116280
Takanori Hidane, T. Fukui, M. Demura, Shintaro Morisada, K. Ohto, H. Kawakita
ABSTRACT Phycobiliprotein (PB), which is produced by cyanobacteria, has potential applications as a valuable pharmaceutical product. In this study, PB was separated by using a nonwoven-fabric membrane (Rx-1) that contained quaternary amino groups. PB was extracted from a Nostoc commune, which is a type of microalga, by disrupting the cell walls by a freeze–thaw method. Two types of biomolecules, namely PB and other biomolecules X, were identified by gel permeation chromatography. Permeation of the PB-containing solution through Rx-1 increased the purity of the PB in the filtrate from 0.25 to 0.45. The adsorption constant (K p) and maximum adsorbed amount of each protein on Rx-1 (q max) were determined by fitting the experimental data to a mathematical model. The obtained values for K p and q max were used to simulate scaled-up treatment of a PB-containing solution. Permeation of a PB-containing solution (3.0 L at 1.2 × 10−3 m3/h) through Rx-1 (volume of scale-up membrane, 8.0 × 10−4 m3) enabled PB separation for 26 h. Further PB purification could be achieved by using the Rx-1 membrane in combination with precipitation with ammonium sulfate solution and an ultrafiltration membrane.
{"title":"Separation of Phycobiliprotein from Nostoc Commune by Using Ion-Exchange Membrane with Quaternary Amine","authors":"Takanori Hidane, T. Fukui, M. Demura, Shintaro Morisada, K. Ohto, H. Kawakita","doi":"10.1080/07366299.2022.2116280","DOIUrl":"https://doi.org/10.1080/07366299.2022.2116280","url":null,"abstract":"ABSTRACT Phycobiliprotein (PB), which is produced by cyanobacteria, has potential applications as a valuable pharmaceutical product. In this study, PB was separated by using a nonwoven-fabric membrane (Rx-1) that contained quaternary amino groups. PB was extracted from a Nostoc commune, which is a type of microalga, by disrupting the cell walls by a freeze–thaw method. Two types of biomolecules, namely PB and other biomolecules X, were identified by gel permeation chromatography. Permeation of the PB-containing solution through Rx-1 increased the purity of the PB in the filtrate from 0.25 to 0.45. The adsorption constant (K p) and maximum adsorbed amount of each protein on Rx-1 (q max) were determined by fitting the experimental data to a mathematical model. The obtained values for K p and q max were used to simulate scaled-up treatment of a PB-containing solution. Permeation of a PB-containing solution (3.0 L at 1.2 × 10−3 m3/h) through Rx-1 (volume of scale-up membrane, 8.0 × 10−4 m3) enabled PB separation for 26 h. Further PB purification could be achieved by using the Rx-1 membrane in combination with precipitation with ammonium sulfate solution and an ultrafiltration membrane.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"20 - 35"},"PeriodicalIF":2.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48580882","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}
ABSTRACT Extraction of gold by adsorption is being concerned because of easy operation, low cost and non-pollution for the present. Lignin and its derivatives are considered to be the most promising adsorbent due to abundance and environmental friendliness. In this work, gold was extracted from the leachate of copper anode slime by quaternary ammonium rice husk lignin (QARHL). QARHL was synthesized and characterized by Fourier Transform Infrared Spectrometry (FTIR), Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS) and Thermogravimetric Analysis and Differential Scanning Calorimetry (TG-DSC). The influence of adsorption time, dosage of adsorbent and temperature on adsorption were investigated. The adsorption mechanism of QARHL for gold was explored by Scanning Electron Microscope (SEM), FTIR and X-ray Diffractometry (XRD). The results showed that QARHL had excellent thermostability and contained a large number of quaternary ammonium groups and hydroxyl groups. The saturated adsorption capacity reached 220.70 mg•g-1 and the time of equilibrium was 120 min. The adsorption was easy to occur spontaneously and obeyed the models of pseudo-second order and Langmuir. AuCl4- was reduced to Au(0) by phenolic hydroxyl after ion exchange. The new process could be used to recovery gold from gold-containing raw materials without pretreatment. It is possible to extract gold effectively, economically and environmentally friendly.
{"title":"Extraction of Gold from the Leachate of Copper Anode Slime by Quaternary Ammonium Rice Husk Lignin","authors":"Bao-ping Zhang, Yin Wang, Guo-dong Lin, Heng Zhang","doi":"10.1080/07366299.2022.2115845","DOIUrl":"https://doi.org/10.1080/07366299.2022.2115845","url":null,"abstract":"ABSTRACT Extraction of gold by adsorption is being concerned because of easy operation, low cost and non-pollution for the present. Lignin and its derivatives are considered to be the most promising adsorbent due to abundance and environmental friendliness. In this work, gold was extracted from the leachate of copper anode slime by quaternary ammonium rice husk lignin (QARHL). QARHL was synthesized and characterized by Fourier Transform Infrared Spectrometry (FTIR), Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS) and Thermogravimetric Analysis and Differential Scanning Calorimetry (TG-DSC). The influence of adsorption time, dosage of adsorbent and temperature on adsorption were investigated. The adsorption mechanism of QARHL for gold was explored by Scanning Electron Microscope (SEM), FTIR and X-ray Diffractometry (XRD). The results showed that QARHL had excellent thermostability and contained a large number of quaternary ammonium groups and hydroxyl groups. The saturated adsorption capacity reached 220.70 mg•g-1 and the time of equilibrium was 120 min. The adsorption was easy to occur spontaneously and obeyed the models of pseudo-second order and Langmuir. AuCl4- was reduced to Au(0) by phenolic hydroxyl after ion exchange. The new process could be used to recovery gold from gold-containing raw materials without pretreatment. It is possible to extract gold effectively, economically and environmentally friendly. ","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"41 1","pages":"1 - 19"},"PeriodicalIF":2.0,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47136035","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 : 2022-06-21DOI: 10.1080/07366299.2022.2079502
K. N. Kmak, J. Despotopulos, N. Scielzo
ABSTRACT The separation of trace hafnium from bulk tungsten alloys is of interest for isotope harvesting at the National Superconducting Cyclotron Laboratory and the Facility for Rare Ion Beams because 172Hf, the parent of 172Lu, accumulates in tungsten alloy beam blockers at these facilities. In this work, a procedure for the separation of trace hafnium from a bulk tungsten alloy (454 g) was established using tracer isotopes (175Hf, 88Zr, 173Lu, and 88Y). The procedure employed dissolution in an HF–HNO3 solution followed by a calcium fluoride precipitation, and then extraction chromatography was used for more selective separation steps. Two stages of column separations using LN resin (HDEHP based) and TRU resin (CMPO based) were performed. Gamma-ray spectroscopy and mass spectrometry were used to analyze the final hafnium sample and follow the steps in the chemical processing. The final recovery of hafnium was high (90 ± 8)%, and the mass of tungsten and other transition metals was reduced to near background levels (as determined by ICP-MS of the blank acid solutions). Zirconium follows hafnium quantitatively in this procedure; there was no detectable 173Lu in the final hafnium sample.
{"title":"Development of Chemical Procedures for Isotope Harvesting: Separation of Trace Hafnium from Tungsten","authors":"K. N. Kmak, J. Despotopulos, N. Scielzo","doi":"10.1080/07366299.2022.2079502","DOIUrl":"https://doi.org/10.1080/07366299.2022.2079502","url":null,"abstract":"ABSTRACT The separation of trace hafnium from bulk tungsten alloys is of interest for isotope harvesting at the National Superconducting Cyclotron Laboratory and the Facility for Rare Ion Beams because 172Hf, the parent of 172Lu, accumulates in tungsten alloy beam blockers at these facilities. In this work, a procedure for the separation of trace hafnium from a bulk tungsten alloy (454 g) was established using tracer isotopes (175Hf, 88Zr, 173Lu, and 88Y). The procedure employed dissolution in an HF–HNO3 solution followed by a calcium fluoride precipitation, and then extraction chromatography was used for more selective separation steps. Two stages of column separations using LN resin (HDEHP based) and TRU resin (CMPO based) were performed. Gamma-ray spectroscopy and mass spectrometry were used to analyze the final hafnium sample and follow the steps in the chemical processing. The final recovery of hafnium was high (90 ± 8)%, and the mass of tungsten and other transition metals was reduced to near background levels (as determined by ICP-MS of the blank acid solutions). Zirconium follows hafnium quantitatively in this procedure; there was no detectable 173Lu in the final hafnium sample.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"40 1","pages":"718 - 734"},"PeriodicalIF":2.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49538109","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 : 2022-05-29DOI: 10.1080/07366299.2022.2074501
B. Mahanty, P. Mohapatra, A. Leoncini, J. Huskens, W. Verboom
ABSTRACT Liquid–liquid extraction and liquid membrane transport behavior of tetravalent actinide ions viz. Th(IV), Np(IV), and Pu(IV) were investigated for the first time using a diglycolamide (DGA) based dendrimer with a tris(2-aminoethyl)amine (TREN) scaffold as the organic extractant. The generation of 1 dendrimer with six DGA pendent moieties (termed as TREN-G1-DenDGA) extracted Np(IV) more effectively than the other two ions, the trend being Np(IV) > Pu(IV) > Th(IV). The extraction studies of Np(IV) from 3 M HNO3 indicated a 1:1 (metal:ligand) species and the extraction efficiency increased with increasing nitric acid concentration (1–6 M). The transport efficiency of Np(IV) increased with the nitric acid concentration (1–6 M) as well as with the ligand concentration. A very low concentration of 5.75 × 10−4 M ligand, when used as the carrier, resulted in the transport of ca. 25% metal ion transport in 5 h, which increased to >85% with 4.4 × 10−3 M ligand. The transport efficiency of the metal ion across the SLM followed the trend Np(IV) > Th(IV) > Pu(IV). The membrane stability was not satisfactory as seen over a period of 5 days suggesting long-term use may require regular replenishment of the carrier solvent. The effective diffusion coefficient (D eff) of Np(IV)-TREN-G1-DenDGA were determined by the lag-time method and was found to be 5.1 × 10−8 cm2/s.
{"title":"Liquid–Liquid Extraction and Supported Liquid Membrane Transport of Neptunium(IV) Across a Flat-Sheet Supported Liquid Membrane Containing a TREN-DGA Derivative","authors":"B. Mahanty, P. Mohapatra, A. Leoncini, J. Huskens, W. Verboom","doi":"10.1080/07366299.2022.2074501","DOIUrl":"https://doi.org/10.1080/07366299.2022.2074501","url":null,"abstract":"ABSTRACT Liquid–liquid extraction and liquid membrane transport behavior of tetravalent actinide ions viz. Th(IV), Np(IV), and Pu(IV) were investigated for the first time using a diglycolamide (DGA) based dendrimer with a tris(2-aminoethyl)amine (TREN) scaffold as the organic extractant. The generation of 1 dendrimer with six DGA pendent moieties (termed as TREN-G1-DenDGA) extracted Np(IV) more effectively than the other two ions, the trend being Np(IV) > Pu(IV) > Th(IV). The extraction studies of Np(IV) from 3 M HNO3 indicated a 1:1 (metal:ligand) species and the extraction efficiency increased with increasing nitric acid concentration (1–6 M). The transport efficiency of Np(IV) increased with the nitric acid concentration (1–6 M) as well as with the ligand concentration. A very low concentration of 5.75 × 10−4 M ligand, when used as the carrier, resulted in the transport of ca. 25% metal ion transport in 5 h, which increased to >85% with 4.4 × 10−3 M ligand. The transport efficiency of the metal ion across the SLM followed the trend Np(IV) > Th(IV) > Pu(IV). The membrane stability was not satisfactory as seen over a period of 5 days suggesting long-term use may require regular replenishment of the carrier solvent. The effective diffusion coefficient (D eff) of Np(IV)-TREN-G1-DenDGA were determined by the lag-time method and was found to be 5.1 × 10−8 cm2/s.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"40 1","pages":"693 - 717"},"PeriodicalIF":2.0,"publicationDate":"2022-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59691792","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 : 2022-04-20DOI: 10.1080/07366299.2022.2052420
Quanduo Miao, T. Sun, Honglin Chen, Qiang Zheng, W. Duan, Jianchen Wang, Jing Chen
ABSTRACT The crown ether strontium extraction (CESE) process has been developed for the recovery or removal of Sr from acidic high-level liquid waste (HLLW) in China, where the extractant is 4’,4”(5”)-di-(tert-butyldicyclohexano)-18-crown-6 (DtBuCH18C6) and the diluent is n-octanol. When the CESE process was operated in annular centrifugal extractors (ACEs) for demonstration by cold and hot tests, it was found that the outlet aqueous phases had organic-phase entrainment even though ACEs operated at a low rotor speed. For the successful operation of the CESE process in ACEs, effects of the operating and geometrical parameters on the liquid hold-up volume and phase ratio (aqueous phase/organic phase, A/O) of the HNO3 –DtBuCH18C6/n-octanol system in a ϕ20 ACE were systematically investigated to find the cause of the above-mentioned hydrodynamic performance problem of the CESE process using the liquid-fast-separation method. It is shown that the operating and geometrical parameters have effects on the liquid hold-up volume and phase ratio (A/O). Moreover, the phase ratio (A/O) in the separation zone of the rotor is less than 1.5 under most of the present experimental conditions, which shows organic-phase entrainment may easily occur in the outlet aqueous phase. The cause can be that the density difference of two phases is small, viscosity of the organic phase is large, and interfacial tension of the extraction system is low.
{"title":"Liquid Hold-up Volume and Phase Ratio (A/O) of HNO3–DtBuCH18C6/n-Octanol System in an Annular Centrifugal Extractor","authors":"Quanduo Miao, T. Sun, Honglin Chen, Qiang Zheng, W. Duan, Jianchen Wang, Jing Chen","doi":"10.1080/07366299.2022.2052420","DOIUrl":"https://doi.org/10.1080/07366299.2022.2052420","url":null,"abstract":"ABSTRACT The crown ether strontium extraction (CESE) process has been developed for the recovery or removal of Sr from acidic high-level liquid waste (HLLW) in China, where the extractant is 4’,4”(5”)-di-(tert-butyldicyclohexano)-18-crown-6 (DtBuCH18C6) and the diluent is n-octanol. When the CESE process was operated in annular centrifugal extractors (ACEs) for demonstration by cold and hot tests, it was found that the outlet aqueous phases had organic-phase entrainment even though ACEs operated at a low rotor speed. For the successful operation of the CESE process in ACEs, effects of the operating and geometrical parameters on the liquid hold-up volume and phase ratio (aqueous phase/organic phase, A/O) of the HNO3 –DtBuCH18C6/n-octanol system in a ϕ20 ACE were systematically investigated to find the cause of the above-mentioned hydrodynamic performance problem of the CESE process using the liquid-fast-separation method. It is shown that the operating and geometrical parameters have effects on the liquid hold-up volume and phase ratio (A/O). Moreover, the phase ratio (A/O) in the separation zone of the rotor is less than 1.5 under most of the present experimental conditions, which shows organic-phase entrainment may easily occur in the outlet aqueous phase. The cause can be that the density difference of two phases is small, viscosity of the organic phase is large, and interfacial tension of the extraction system is low.","PeriodicalId":22002,"journal":{"name":"Solvent Extraction and Ion Exchange","volume":"40 1","pages":"777 - 799"},"PeriodicalIF":2.0,"publicationDate":"2022-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46531850","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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