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Date submitted2018-05-16
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Date accepted2018-07-22
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Date published2018-10-24
Extraction of copper, cobalt and nickel ions from aqueous solutions by extractant CYANEX 272
- Authors:
- L. A. Voropanova
- V. P. Pukhova
The extractant CYANEX 272, which active component is di(2,4,4-trimethylpentyl)-phosphinic acid (C 8 H 17 ) 2 POOH, is effective for extraction of copper (II), cobalt (II) and nickel (II) ions. The extraction of metal ions using di(2,4,4-trimethylpentyl)-phosphinic acid as an extractant is carried out due to the formation of an organophosphorus complex with wide pH range: copper at pH > 2, cobalt at pH > 3, and nickel at pH > 5. They are extracted with an organic phase: copper at pH = 3-7, cobalt at pH = 4-7, and nickel at pH = 6-9, and precipitate in the organophosphorus compound: copper at pH > 7, cobalt at pH ≥ 8, and nickel at pH ≥ 10. The possibility of separation of copper (II) and cobalt (II) is insignificant, the stripping of copper (II) and nickel (II) happens at pH = 4-6, and the stripping of cobalt (II) and any of nickel (II) – at pH = 5-6. The obtained results of ion extraction of the investigated metals can be used not only for processing of technological solutions, but also for purification of effluents from industrial enterprises and mine waters, heap and underground leaching solutions, etc. from the ions of studied metal ions.
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Date submitted2015-12-19
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Date accepted2016-02-08
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Date published2016-12-23
A technique for selective extraction of ions of gold and silver from hydrochloric solutions with tributylphosphate
- Authors:
- L. A. Voropanova
- N. B. Kokoeva
Extraction is studied by tributylphosphate (TBP) of ions of gold and silver from hydrochloric solutions during the portional and single time feed of extractant in dependence of the initial concentration of metal ions, temperature, concentration of hydrochloric acid, the ratio of organic (О) and water W phases О:W. The initial solutions contained soluble complex chlorides of gold and silver. When dissolving metal chlorides in the solution of common salt and hydrochloric acid, water soluble coordinate compound are formed that contain complex anions [AuCl 2 ] – , [AuCl 4 ] – , [AgCl 2 ] – , [AgCl 3 ] 2– , [AgCl 4 ] 3– , et al. As an extractant we used the tri-butyl ether of phosphoric acid (С 4 Н 9 О) 3 РО hat belongs to oxygen containing neutral extractants. The formation of coordinate (complex) compounds of TBP and metal polychlorides may be treated as the process of solvation of the extracted metal salt by the extractant. For selective extraction of ions of gold and silver from their hydrochloric solutions by tributylphosphate it is run feeding the extractant portionally to the solution at the minimal time of contact between the solution and the extractant; it helps extracting gold almost completely with the few first portions of the extractant at concentrations of 2n HCl 240 g/dm 3 NaCl and the temperature t = 60°С. Meanwhile the extraction of silver is kept to a minimum. Silver is extracted almost completely after the extraction of gold is over; it is done with tributylphosphate as well at concentrations of 3n HCl, 240 g/dm 3 NaCl and the temperature t = 20°С.
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Date submitted2015-08-14
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Date accepted2015-10-07
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Date published2016-04-22
Extraction of ions of silver from hydrochloric acid solutions by tributylphosphate
- Authors:
- L. A. Voropanova
- N. B. Kokoeva
The high results of the silver ions extraction from the hydrochloric acid solutions of tributylphosphate during extractant portional introduction were obtained. The extractant batch inclusion increases silver extraction process and reduces the extractant expenditure. The best extraction results were obtained for the solutions with concentration 3N HCl, 240 NaCl g/dm 3 and temperature t = 20 °C. The principal technological scheme of the silver ions extraction from the hydrochloric acid solutions is presented.
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Date submitted2015-07-27
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Date accepted2015-09-17
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Date published2016-02-24
Electroextraction of cobalt from sulfate-chloride and sulfate solutions of cobalt and manganese in static conditions
- Authors:
- L. P. Khomenko
- L. A. Voropanova
The dependence of the results of electroextraction cobalt and manganese from aqueous solutions of their sulphate and chloride-sulfate solutions under static conditions was investigated. According to the results of current efficiency and specific energy consumption it has been found that the electrowinning of cobalt from aqueous solutions of cobalt and manganese in static conditions using a titanium cathode should be carried out at low concentration of manganese from sulphate-chloride solution without partitions and from sulphate solutions both without and with the perforated partitions separating the electrolytic cell into cathode and anode space.
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Date submitted2014-11-01
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Date accepted2015-01-02
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Date published2015-10-26
Development of an environmentally safe gold extraction method from refractory ores using sodium thiosulfate as an extractant
- Authors:
- Yu. V. Sharikov
- Ilkka Turunen
The article presents the results of a mathematical model development for the process of gold leaching from gold-containing ores and concentrates. A mathematical model has been developed by analyzing the chemistry of reactions and mass transfer processes. On the base of a kinetic extraction model and a hydrodynamic complete mixing model a mathematical model of thiosulfate leaching process in various types batch reactors, complete mixing flow process vessels and complete mixing reactor columns with different numbers of vessels in a column has been developed. The effect of the number of reactors in a column has been investigated and optimal segmentation conditions have been found. Based on the investigation of the process using the mathematical model a control system structure has been designed to provide maximum conversion at the exit area of a reactor column.
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Date submitted2014-10-27
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Date accepted2014-12-28
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Date published2015-08-25
Extraction of rare earth metals of di-2-ethylhexyl phosphoric acid from phosphoric solutions
- Authors:
- O. V. Cheremisina
The paper is devoted to solvent extraction of rare earth metals exemplified by Сe, Y from standard test and industrial solutions of wet-process phosphoric acid with di-2-ethylhexyl phosphoric acid used as extractant. The mechanism of rare earth metals extraction with di-2-ethylhexyl phosphoric acid was determined and studied on the basis of calculated thermodynamic characteristics. The paper considers the influence of impurity ions (Fe 3+ , Mg 2+ , ) on extraction of rare earth metals using industrial solutions. It has also been determined that for a stripping process the use of sulfuric acid solutions in concentration of 2 mol/l is the most preferable.
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Date submitted2014-10-15
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Date accepted2014-12-23
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Date published2015-08-25
Nickel electrolyte purification from ferrum (III) and copper (II) impurities by extraction using a mixture of oleic acid and triethanolamine
- Authors:
- L. A. Voropanova
- N. T. Kisiev
The conditions of the selective and joint extraction of copper and ferrum impurities from a nickel electrolyte by extraction using a mixture of oleic acid and trietanolamine in kerosene were determined: extraction Fe (III) at 3 < рН ≤ 4, 1 ≤ В:О ≤ 4 and t = 40 °C; extraction Cu (II) at 5 ≤ рН ≤ 6, 1 < В:О ≤ 4 and t = 40 °C; joint extraction of copper and ferrum at рН = 5-6, 1 ≤ В:О ≤ 4 and t = 40 °C. The process flow sheet of selective extraction of ferrum and copper from a nickel electrolyte by extraction using a mixture of oleic acid and triethanolamine in kerosene is given.