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1

A calculation model for liquid-liquid extraction of protactinium by 2,6-dimethyl-4-heptanol

100%

Knight A. W. , Eitrheim E. S. , Nelson A. W. , Schultz M. K.

Nukleonika

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2015

|

tom Vol. 60, No. 4, part 2

837--845

EN

Reprocessing of spent nuclear fuel usually employs the solvent extraction technique to recover fissile material, isolate other valuable radionuclides, recover precious metals, and remove contaminants. Effi cient recovery of these species from highly radioactive solutions requires a detailed understanding of reaction conditions and metal speciation that leads to their isolation in pure forms. Due to the complex nature of these systems, identification of ideal reaction conditions for the efficient extraction of specific metals can be challenging. Thus, the development of experimental approaches that have the potential to reduce the number of experiments required to identify ideal conditions are desirable. In this study, a full-factorial experimental design was used to identify the main effects and variable interactions of three chemical parameters on the extraction of protactinium (Pa). Specifi cally we investigated the main effects of the anion concentration (NO3 –, Cl–) extractant concentration, and solution acidity on the overall extraction of protactinium by 2,6-dimethyl-4-heptanol (diisobutylcarbinol; DIBC) from both HCl and HNO3 solutions. Our results indicate that in HCl, the extraction of protactinium was dominated by the solution acidity, while in nitric acid the extraction was strongly effected by the [DIBC]. Based on our results, a mathematical model was derived, that describes the relationship between concentrations of anions, extractant, and solution acidity and the expected values of Pa distribution coefficients in both HCl and HNO3. This study demonstrates the potential to predict the distribution coefficient values, based upon a mathematical model generated by a full-factorial experimental design.

2

A calculation model for liquid-liquid extraction of protactinium by 2,6-dimethyl-4-heptanol

100%

Knight A. W. , Eitrheim E. S. , Nelson A. W. , Schultz M. K.

Nukleonika

|

2015

|

tom 60

|

nr 4

837-845

EN

Reprocessing of spent nuclear fuel usually employs the solvent extraction technique to recover fissile material, isolate other valuable radionuclides, recover precious metals, and remove contaminants. Efficient recovery of these species from highly radioactive solutions requires a detailed understanding of reaction conditions and metal speciation that leads to their isolation in pure forms. Due to the complex nature of these systems, identification of ideal reaction conditions for the efficient extraction of specific metals can be challenging. Thus, the development of experimental approaches that have the potential to reduce the number of experiments required to identify ideal conditions are desirable. In this study, a full-factorial experimental design was used to identify the main effects and variable interactions of three chemical parameters on the extraction of protactinium (Pa). Specifically we investigated the main effects of the anion concentration (NO3-, Cl-) extractant concentration, and solution acidity on the overall extraction of protactinium by 2,6-dimethyl-4-heptanol (diisobutylcarbinol; DIBC) from both HCl and HNO3 solutions. Our results indicate that in HCl, the extraction of protactinium was dominated by the solution acidity, while in nitric acid the extraction was strongly effected by the [DIBC]. Based on our results, a mathematical model was derived, that describes the relationship between concentrations of anions, extractant, and solution acidity and the expected values of Pa distribution coefficients in both HCl and HNO3. This study demonstrates the potential to predict the distribution coefficient values, based upon a mathematical model generated by a full-factorial experimental design.

3

Parametric optimization of rice bran oil extraction using response surface methodology

100%

Ahmad S. W. , Javed F. , Ahmad S. , Akram M. , Rehman A.

Polish Journal of Chemical Technology

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2016

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tom Vol. 18, nr 3

103--109

EN

Use of bran oil in various edible and nonedible industries is very common. In this research work, efficient and optimized methodology for the recovery of rice bran oil has been investigated. The present statistical study includes parametric optimization, based on experimental results of rice bran oil extraction. In this study, three solvents, acetone, ethanol and solvent mixture (SM) [acetone: ethanol (1:1 v/v)] were employed in extraction investigations. Response surface methodology (RSM), an optimization technique, was exploited for this purpose. A five level central composite design (CCD) consisting four operating parameter, like temperature, stirring rate, solvent-bran ratio and contact time were examined to optimize rice bran oil extraction. Experimental results showed that oil recovery can be enhanced from 71% to 82% when temperature, solvent-bran ratio, stirring rate and contact time were kept at 55°C, 6:1, 180 rpm and 45 minutes, respectively while fixing the pH of the mixture at 7.1.

4

Hydrometallurgical treatment of hazardous copper Cottrell dusts to recover copper

100%

Alguacil F. J. , Regel-Rosocka M.

Physicochemical Problems of Mineral Processing

|

2018

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tom Vol. 54, iss. 3

771--780

EN

Copper flue dusts, or copper Cottrell dusts, from three types of copper smelting furnaces were leached with different ammonia-based reagents (ammonium chloride, ammonium carbonate and aqueous ammonia solutions) to dissolve the oxidised copper species via the formation of copper-ammonia complexes, so that most of the copper-accompanying metals, especially iron, remained in the solid residue. Such copper-bearing dusts are not only valuable secondary source of copper but also are considered as hazardous materials and cannot be dumped as such. Therefore, two procedures for copper dust treatment are proposed, one of them includes ammonium-based leaching, liquid-liquid extraction with LIX 860 (aldoxime), LIX 84 (ketoxime) or LIX 54 (β-diketone) and electrowinning to grade A copper cathode. The other one covers also ammonium-based leaching followed by cementation with zinc to copper cement as a final product.

5

Extraction of rubidium ion from brine solutions by dicyclohexano-18-crown-6 / ionic liquid system

100%

Huang D. , Ma G. , Lv P. , Zhou Q.

Polish Journal of Chemical Technology

|

2023

|

tom Vol. 25, nr 1

61--68

EN

Separation among rubidium and potassium ions from salt lake brines remains challenging. In this work, a typical room temperature ionic liquid 1-ethyl-3-metyhlimidazaolium bis(trifluoromethylsulfonyl)imide ([C2mim+][NTf2-]) was used as diluent and synergistic extractant, dicyclohexano-18-crown-6 (DCH18C6) was used as extractant to extract rubidium ions from brine solutions which contain high concentrations of potassium ions was investigated. Under the optimal conditions, the single extraction efficiency of rubidium ions was up 93.63%. The thermodynamic parameters of the rubidium ion extraction were obtained. Based on the slope analysis method, the extracted species in the organic phase were ascertained as 1:1 complex. UV-visible has been performed to investigate the ion concentration of ionic liquid before and after the interaction of metal ions and ligands. Rubidium ions in [Rb · DCH18C6]+ complex were stripped by 2.5 mol · L-1 NH4NO3. The extraction system offers high efficiency, simplicity and environmentally friendly application prospect to separate rubidium from brine solutions.

6

Hydrometallurgical recovery of copper from leach liquor of polymetallic nodules in solvent extraction process

100%

Pospiech B.

Journal of Achievements in Materials and Manufacturing Engineering

|

2012

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tom Vol. 55, nr 2

777--781

EN

Purpose: Purpose of this paper is to present the possibilities of copper(II) recovery from the synthetic sulphate leach liquor containing cobalt(II), nickel(II) and manganese(II). Design/methodology/approach: The investigations have been undertaken in order to determine the influence of major parameters on the extraction process of copper(II) from the leach liquor of polymetallic manganese nodules. Copper(II) ions were extracted with Kelex 100 and LIX 70 in kerosene. The effect of different parameters such as pH of aqueous phase, extractants concentration in the organic phase, concentration of sulphuric acid as the stripping reagent were investigated. Findings: The optimal conditions of metal ions selectivity extraction have been determined. Over 99% of Cu(II) can be effectively extracted with 5% Kelex 100 and 10% LIX 70 at pH of 2.0 from model leach liquor in the presence of Co(II), Ni(II) and Mn(II), while less than 10% of the other metals is transported to the organic phase. The selectivity of Cu(II) extraction over Co(II), Ni(II) and Mn(II) with Kelex 100 depended upon the acidity of aqueous solution and the selectivity increased with decreasing of pH in the feed solution. Separation of Cu(II) from these metal ions is very effective. Cu(II) can be recovered successfully from the loaded organic phase with Kelex 100 through stripping with 2.0 M H2SO4. Practical implications: The results can be used during the hydrometallurgical recovery of metals from nodules on the industrial scale. Originality/value: The study on the solvent extraction of Cu(II) using LIX 70 and Kelex 100 from leach liquor of polymetallic manganese nodules has not been reported yet. Conducting this research is therefore the most reasonable and necessary.

7

Preparation of Nickel Nanoparticles Using Nickel Raffinate Separated by Solvent Extraction from The Spent FeCl3 Etching Solution

100%

Park I.-J. , Swain B. , Kim D.-W. , Kim G.-H. , Han D.-H. , Jung H.-C.

Archives of Metallurgy and Materials

|

2019

|

tom Vol. 64, iss. 2

531--534

EN

FeCl3 bearing etching solution is mainly used for etching of metals used in shadow masks, PCBs and so on. Due course of Invar alloy etching process the FeCl3 bearing etching solution get contaminated with Ni2+ which affect adversely the etching efficiency. Hence, FeCl3 bearing etching solution discarded after several cycle of operation causes an environmental and economic problem. To address both the issues the etching solution was purified through solvent extraction and remained Ni2+ recovered by wet chemical reduction using hydrazine. For optimum Fe3+ extraction efficiency, various extraction parameter were optimized and size and morphology of the recovered pure Ni powder was analyzed. The reported process is a simple process to purify and recover Ni from industry etching solution.

8

The Influence of Steric Effect and Alkyl Chain Length on Extraction of the Complexes of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with 1-Alkyl-2-methylimidazoles

100%

Lenarcik B. , Adach A. , Radzymińska-Lenarcik E.

Polish Journal of Chemistry

|

1999

|

tom Vol. 73, nr 8

1273-1281

EN

Extraction of complexes of 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-propyl-2-methylimidazole and 1-butyl-2-methylimidazole with Co(II), Ni(ii0, Cu(II), Zn(II) and Cd(II) from aqueous solutions (I=0.5 at 298 K) with benzyl alcohol was investigated. For each system, the composition of the extracted species, their partition constans and the pH1/2 were determined.

9

Recovery of zinc from arduous wastes using solvent extraction technique. Part II, Pilot plant tests

100%

Gotfryd L. , Chmielarz A. , Szołomicki Z.

Physicochemical Problems of Mineral Processing

|

2011

|

tom Vol. 47

249-258

EN

Solvent extraction technique using 40 vol. % bis(2-ethylhexyl)phosphoric acid as an extractant was applied for recovery of zinc from technological solutions. Crude zinc oxides from Waelz processing of electric arc furnace dusts or ferrous waste of zinc hydrometallurgy were used for preparation of feed solutions by leaching them with diluted sulfuric acid and by pre-liminary hydrometallurgical purification. The studies were conducted step by step from labor-atory to advanced pilot plant tests in continuously operating installation. Part II describes preparations and results of pilot plant counter-current experiments performed using laboratory extractive system, built from a train of mixer-settler type extractors, set in changeable countercurrent manner, necessary pumps and automation systems, coupling pH measurements with neutralization agent supply. Excellent results in a form of very pure zinc sulfate solutions were obtained. ZnSO4 concentrations are appropriate and the purity of the strip solutions very good. Comparison of natural and accelerated method of zinc extraction is done.

10

Recovery of zinc from arduous wastes using solvent extraction technique. Part I. Preliminary laboratory studies

100%

Gotfryd L. , Chmielarz A. , Szołomicki Z.

Physicochemical Problems of Mineral Processing

|

2011

|

tom Vol. 47

149-158

EN

Solvent extraction technique with 40 volume percent of bis(2-ethylhexyl)phosphoric acid as an extractant was applied for recovery of zinc from technological solutions. Crude zinc oxides from Waelz processing of electric arc furnace dusts or ferrous waste of zinc hydrometallurgy were used for preparation of feed solutions by leaching them with diluted sulfuric acid and by preliminary hydrometallurgical purification. The studies were conducted step by step from elementary laboratory experiment to advanced level of pilot plant tests in a continuously operating installation consisting of a counter-current set of mixer-settler type extractors and necessary equipment. The paper describes the course and results of initial laboratory works undertaken to choose proper extractant and establish conditions for further successful zinc extraction in the pilot plant installation.

11

Studies on platinum recovery from solutions after leaching of spent catalysts by solvent extraction

100%

Pośpiech B.

Physicochemical Problems of Mineral Processing

|

2012

|

tom Vol. 48, iss. 1

239-246

EN

The results of studies on the separation of platinum(IV) ions by solvent extraction from aqueous solutions after leaching of spent catalysts have been reviewed. The following processes have been discussed: acid leaching of spent catalysts and solvent extraction of platinum(IV) ions by using organophosphorous acids, amines and oximes as the extractants. In hydrometallurgical leaching of spent automobile catalysts many reagents such as aqua regia solutions, aluminum chloride solutions with low concentrations of nitric acid as an oxidant, and sodium cyanide solutions were tested. After leaching, the metal ions in leach solutions have to be separated and purified by solvent extraction. Typical leach liquor contains economically valuable metal ions such as platinum(IV), palladium(II), rhodium(III) nickel(II) and manganese(II). The influence of several factors on the efficiency and selectivity of platinum(IV) ions extraction from leach solutions was shown. The optimum conditions of these processes were also reported on the ground of literature survey.

12

Nowe rozwiązania w rafinacji rozpuszczalnikowej destylatorów olejowych

100%

Szeja W. , Hehlmann J. , Specjał W. , Markiewicz M. , Stokłosa T. , Zbierzchowski L. , Żylik W.

Przemysł Chemiczny

|

2003

|

tom T. 82, nr 8-9

586-589

13

Effect of coexisting sodium ion extractive separation of metal ions with calix[4]arene tetracarboxylic acid

100%

Ohto K. , Shioya A. , Higuchi H. , Oshima T. , Inoue K.

Ars Separatoria Acta

|

2002

|

tom No. 1

61-70

EN

Solvent extraction of metal ions with calix[4]arene tetracarboxylic acid has been carried out to elucidate effect of coexisting sodium ion. Extraction of metal ions examined, Pb(II), Fe(III), Cu(II), Zn(II), Ni(II), and Co(II), is enhanced by the addition of sodium ion. The enhancement degree of the metal extraction is not necessarily in proportion to the added sodium concentration. The addition of trace amount of sodium ion is necessary to specifically complex for calix[4]arene tetracarboxylic acid and to enhance the extraction ability. However, the addition of excessive amounts of sodium suppresses the extraction of other metal ions, since they act as a competitive ion with other metal ions; The relation between extractive pH1/2 of metal ions and sodium concentration is shown. Mutual separation of metal ions by using additional sodium ion is also investigated. Although complete mutual separation of three metal ions, Pb(II), Cu(II), and Zn(II), has not been achieved, the possibility that the sodium addition will enhance not only the extraction ability but also the separation efficiency is suggested.

14

Separation of Co(II), Cu(II), Ni(II) and Mn(II) from synthetic hydrochloric acid leaching solution of spent lithium ion batteries by solvent extraction

100%

Nguyen V. N. H. , Lee M. S.

Physicochemical Problems of Mineral Processing

|

2020

|

tom Vol. 56, iss. 4

699--610

EN

Spent lithium ion batteries contain valuable critical metals such as cobalt, copper, lithium and nickel. In order to develop a process for the separation of the divalent metal ions from spent lithium ion batteries, solvent extraction experiments were performed by employing synthetic hydrochloric acid leaching solution. The synthetic solution contained Cu(II), Co(II), Mn(II) and Ni(II) and its acidity was 3 M HCl. Extraction with Aliquat 336 led to selective extraction of Cu(II) with a small amount of Co(II). After adding NaCl to the Cu(II) free raffinate to enhance the complex formation of Co(II), Co(II) was selectively extracted into Aliquat 336 together with Mn(II). The small amount of Mn(II) in the loaded Aliquat 336 was scrubbed by pure Co(II) solution. After adjusting the pH of the raffinate to 3, 91,3% of Mn(II) was selectively extracted over Ni(II) by the mixture of D2EHPA and Alamine 336. In this extraction, the mole fraction of D2EHPA in the mixture affected the extraction of Mn(II). McCabe-Thiele diagrams for the extraction of Cu(II) and Co(II) were constructed. Batch simulation experiments for the three stage counter-current extraction verified the selective extraction of the target metal ions in each extraction step. Namely, the total extraction percentage of Cu(II) and Co(II) was 71.6% and 98.8% respectively. Most metals in the loaded organic phase were stripped completely with the appropriate agents (1.0 M H2SO4 for Cu(II), 0.1 M H2SO4 for Co(II) and 0.3 M HCl for Mn(II) stripping). A process was proposed to separate the metal ions by solvent extraction.

15

Improvement of metal separation process from synthetic hydrochloric acid leaching solution of spent lithium ion batteries by solvent extraction and ion exchange

100%

Nguyen V. N. H. , Lee M. S.

Physicochemical Problems of Mineral Processing

|

2021

|

tom Vol. 57, iss. 4

1--17

EN

Spent lithium-ion batteries (LIBs) are good secondary resources for recycle and reuse. To develop a process for the separation of Cu(II), Co(II), Mn(II), Ni(II) and Li(I) with high purity from spent LIBs and circumvent some drawbacks of the previous work, solvent extraction and ion exchange experiments were done in this work. The synthetic hydrochloric acid leaching solution of 3 M was employed. Compared to Aliquat 336 (N-Methyl- N, N, N-trioctyl ammonium chloride), extraction with Cyanex 301 (bis(2,4,4-trimethylpentyl) dithiophosphinic acid) led to selective extraction of Cu(II) over other metal ions. Employing ion exchange with TEVA-SCN resin can completely separate Co(II) over Mn(II). After adjusting the pH of Co(II) free raffinate to 3, Mn(II) was quantitatively extracted by the mixture of Alamine 336 (mixture of tri-octyl/decyl amine) and PC 88A (2-ethylhexyl hydrogen-2-ethylhexylphosphonate) with two stage cross-current extraction. The synthesized ionic liquid (ALi-CY) was used for complete extraction of Ni(II), whereas Li(I) remained in final raffinate. The metal ions in the loaded organic phase were completely stripped with the proper agents (5% aqua regia for Cu(II), 5% NH3 for Co(II), weak H2SO4 solution for Mn(II) and Ni(II) stripping, respectively). The experimental results revealed that purity of the metal ions in stripping solution was higher than 99.9%. A flowsheet was suggested to separate metal ions from the HCl leaching solutions of spent LIBs.

16

Direct measurements of reaction time for extractive processes

88%

Gotfryd L. , Becker K. , Pietek G. , Szołomicki Z. , Piwowonska J.

Physicochemical Problems of Mineral Processing

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2016

|

tom Vol. 52, iss. 2

909--919

EN

Extraction times for selected metal cations (Mg2+, Al3+, Zn2+, Cd2+, Cu2+, Ni2+, Co2+, Mn2+, Fe2+ and Fe3+) have been measured using cation-exchanging extractants - Versatic 10 (neodecanoic acid), DEHPA (bis(2-ethylhexyl)phosphoric acid) and Cyanex 272 (bis(2,4,4-trimetylpentyl)phosphinic acid). Data was collected directly by measuring and recording pH of the two phase reaction mixture with maintaining continuity of the aqueous phase. Similarly, the stripping rate of selected cations (Mg2+, Al3+, Zn2+, Cu2+, Ni2+, Co2+) in a sulphuric acid solution was measured. Viscosities of organic phases, saturated with cations, were measured before their stripping. Additionally, the extraction dependence of Mg2+, Al3+, Fe2+ and Fe3+ on pH was measured using Versatic 10 at various concentrations (7.5, 15 and 30 %).

17

Characterization of solvents containing CyMe4-BTPhen in selected cyclohexanone-based diluents after irradiation by accelerated electrons

88%

Distler P. , Kondé J. , John J. , Hájková Z. , Švehla J. , Grüner B.

Nukleonika

|

2015

|

tom 60

|

nr 4

885-891

EN

Radiation stability of CyMe4-BTPhen was examined in systems with three selected cyclohexanone-based diluents. Accelerated electrons were used as a source of ionizing radiation. The CyMe4-BTPhen radiation degradation identification and characterization of the degradation products were performed by high performance liquid chromatography (HPLC) and mass spectrometry (MS) analyses. Residual concentrations of tested ligand were determined. Moreover, extraction properties of the solvents irradiated at two different doses were compared with the extraction properties of non-irradiated solvents to estimate the influence of the presence of degradation products in the organic phase.

18

New approach for third phase investigation in solvent extraction system

88%

Borkowski M.

Ars Separatoria Acta

|

2008

|

tom No. 6

31-40

EN

The phenomenon of third phase formation in different liquid extraction systems is well known for more than 50 years but until now a good mathematical model that could predict the third phase formation has not been developed. The third phase is unwanted in extraction systems because, for example, in nuclear fuel reprocessing it can cause criticality problems. However, the third phase may be a useful tool in other technologies. In this paper a new approach to third phase investigation is proposed. This new approach eliminates the aqueous phase, simplifies the system and gives new insight in the nature the third phase. It is a step forward in understanding of the mechanism governing the formation of third phase. This new approach could quickly provide sufficient data to develop a comprehensive model.

19

Characterization of solvents containing CyMe4-BTPhen in selected cyclohexanone-based diluents after irradiation by accelerated electrons

88%

Distler P. , Kondé J. , John J. , Hájková Z. , Švehla J. , Grüner B.

Nukleonika

|

2015

|

tom Vol. 60, No. 4, part 2

885--891

EN

Radiation stability of CyMe4-BTPhen was examined in systems with three selected cyclohexanone-based diluents. Accelerated electrons were used as a source of ionizing radiation. The CyMe4-BTPhen radiation degradation identifi cation and characterization of the degradation products were performed by high performance liquid chromatography (HPLC) and mass spectrometry (MS) analyses. Residual concentrations of tested ligand were determined. Moreover, extraction properties of the solvents irradiated at two different doses were compared with the extraction properties of non-irradiated solvents to estimate the influence of the presence of degradation products in the organic phase.

20

Solvent extraction of copper(II) from chloride solutions using 1,1′-dialkyl-2,2′ bibenzimidazoles as extractants

88%

Mądrzak-Litwa I. , Borowiak-Resterna A.

Physicochemical Problems of Mineral Processing

|

2019

|

tom Vol. 55, iss. 5

1165--1178

EN

The solvent extraction ability of 1,1′-dialkyl-2,2′-bibenzimidazoles (L) for the recovery of copper(II) ions from aqueous chloride solutions has been investigated. It was found that 1,1′-didecyl- 2,2′-bibenzimidazole is a useful extractant for the separation of copper(II) ions from both weakly and strongly acidic solutions. Copper(II) can be effectively stripped of organic solutions by a water or ammonia solution in a one-stage process. In low acidity media (pH feed > 1), the extraction percentage of Cu(II) increases with an increase in metal ions and chloride concentrations. Copper(II) ions are extracted as binuclear complexes (CuCl2) 2L2 (L = extractant). The constructed McCabe−Thiele diagram shows that the reduction of copper(II) ions concentration from 25 to approximately 5 g/dm3 in an aqueous feed is possible in two extraction stages. When [HCl] feed ≥ 1 M, (LH+)2(CuCl 4 2)L complex is formed. From the strongly acidic solutions ([HCl] = [LiCl] = 4 M), almost 100% of copper(II) ions can be removed by 1,1′-didecyl-2,2′-bibenzimidazole. Benzyl alcohol, used as an organic phase modifier, enables the selective extraction of copper(II) over zinc(II) ions from a weakly acidic chloride solution.