Extraction of americium with benzyldibutylamine from nitrate solutions

1979 ◽  
Vol 44 (8) ◽  
pp. 2366-2372 ◽  
Author(s):  
Věra Jedináková ◽  
Jana Cibulková ◽  
Libor Kuča
Keyword(s):  
Nitric Acid ◽  
Chemical Analysis ◽  
Ir Spectra ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Nuclear Fission ◽  
Salting Out ◽  
Nitrate Medium ◽  
Separation Factors ◽  
Nitrate Solutions

The extraction of Am(III) with benzyldibutylamine from nitrate medium was examined in dependence on the concentration of nitric acid, kind and concentration of the salting-out agent in the aqueous phase, and on the solvent. Am(III) is extracted into the organic phase in the form of {(R3NH+)α, Am(NO3)52-}. The IR spectra of the organic phase are discussed and confronted with the results of the chemical analysis of the organic phase. The extraction of Am(III) and of lanthanoids was found to be considerably higher than that of some products of corrosion and nuclear fission (Cs, Sr, Zr, Fe), which is documented by the high values of the separation factors.

Extraction of Am(III) by benzyldibutylamine from nitrate solutions of lanthanides

1981 ◽  
Vol 46 (1) ◽  
pp. 194-200 ◽  
Author(s):  
Marta Vojtíšková ◽  
Věra Jedináková ◽  
Libor Kuča
Keyword(s):  
Nitric Acid ◽  
Nuclear Fuel ◽  
Organic Phase ◽  
Spent Nuclear Fuel ◽  
Optimum Conditions ◽  
Separation Factors ◽  
Nitrate Solutions

Benzyldibutylamine is a suitable extractant for the separation of Am(III) and Ln(III) from the acidic nitrate solutions. The effect of lanthanides and yttrium on the extraction of Am(III) has been followed under the conditions modelling the content of these components in the spent nuclear fuel. The separation factors αAm/Ln were evaluated for the optimum conditions found for the separation of Am(III) from the lanthanides. The coextraction of nitric acid and water into the organic phase is discussed.

Extraction of hafnium(IV) with organophosphorus reagents from solutions of mineral acids mixtures

1979 ◽  
Vol 44 (12) ◽  
pp. 3656-3664
Author(s):  
Oldřich Navrátil ◽  
Jiří Smola ◽  
Rostislav Kolouch
Keyword(s):  
Ionic Strength ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Synergic Effect ◽  
Salting Out ◽  
Initial Concentration ◽  
Mixed Complexes ◽  
Synergic Extraction ◽  
Mineral Acids

Extraction of hafnium(IV) was studied from solutions of mixtures of perchloric and nitric acids and of perchloric and hydrochloric acids for constant ionic strength, I = 2, 4, 6, or 8, and for cHf 4 . 10-4 mol l-1. The organic phase was constituted by solutions of some acidic or neutral organophosphorus reagents or of 2-thenoyltrifluoroacetone, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, or N-benzoyl-N-phenylhydroxylamine in benzene, chloroform, or n-octane. A pronounced synergic extraction of hafnium proceeds only on applying organophosphorus reagents from an aqueous phase whose acidity is not lower than 3M-(HClO4 + HNO3) or 5M-(HClO4 + HCl). The synergic effect was not affected markedly by a variation of the initial concentration of hafnium in the range 1 . 10-8 -4 .10-4 mol l-1, it lowered with increasing initial concentration of the organophosphorus reagent and decreasing concentration of the H+ ions. It is suggested that the hafnium passes into the organic phase in the form of mixed complexes, the salting-out effect of perchloric acid playing an appreciable part.

scholarly journals Separation of tungsten and rhenium on alumina

2004 ◽  
Vol 69 (8-9) ◽  
pp. 683-688 ◽  
Author(s):  
Jurij Vucina ◽  
Dagoljub Lukic ◽  
Milovan Stoiljkovic
Keyword(s):  
Nitric Acid ◽  
Sodium Chloride ◽  
Aqueous Phase ◽  
Aqueous Media ◽  
Distribution Coefficients ◽  
Experimental Conditions ◽  
Efficient Separation ◽  
Separation Factors ◽  
Ph Range

The conditions for the efficient separation of tungsten(VI) and rhenium (VII) on alumina were established. The distribution coefficients K d for tungstate and perrhenate anions, as well as the separation factors ?(? = KdWO42-/Kd ReO4-) were determined using hydrochloric or nitric acid as the aqueous media. Asolution of sodium chloride in the pH range 2?6 was also examined. Under all the tested experimental conditions, alumina is a much better adsorbent for tungsten than for rhenium. The obtained results indicated that the best separation of these two elements is achieved when 0.01? 0.1 mol dm-3HCl or 1.0mol dm-3 HNO3 are used as the aqueous media. If NaCl is used as the aqueous phase, the best separation is achieved with 0.20 mol dm-3 NaCl pH 4?6. Under these experimental conditions, the breakthrough and saturation capacities of alumina for tungsten at pH4 are 17 and 26 mg W/g Al2O3 respectively. With increasing pH, these values decrease. Thus, at pH 6 they are only 4 and 13 mg W/g Al2O3, respectively.

The composition of complexes in the organic phase during the extraction of Eu(III) and Am(III) by benzyldibutylamine and benzyltrialkylammonium nitrates

1986 ◽  
Vol 51 (4) ◽  
pp. 791-800
Author(s):  
Libor Kuča ◽  
Věra Jedináková ◽  
Lubomír Daňo
Keyword(s):  
Metal Complex ◽  
Organic Phase ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Phase Extraction ◽  
Salting Out ◽  
Nitrate Ions ◽  
Nitrate Complexes ◽  
Composition Of Complexes ◽  
Nitrate Solutions

The extraction of americium and europium from acid nitrate solutions by benzene solutions of benzyldibutylamine nitrate (I) and quaternary ammonium salts benzyllauryldimethylammonium nitrate (II) and benzyltrioctylammonium nitrate (III) has been studied. During extraction with I, {(R3NH+)2, Me(NO3)2-5} is formed in the organic phase, extraction with II yields {(R4N+), Me(NO3)-4} and {(R4N+)2, Me(NO3)2-5} is formed during extraction with III. The concentration of nitrate ions does not have an unambiguous effect on the stoichiometry of the extraction. In addition to favouring the formation of the nitrate complexes of Am3+ and Eu3+, which are extracted by amines, nitrate ions also have a nonspecific salting out effect. The changes in the water content in the organic phase in dependence on the concentration of the metal complex suggests that the complex of Eu with II is not hydrated in the organic phase.

scholarly journals DISTRIBUTION OF THORIUM (IV) IONS IN AQUEOUS EXFOLIATING SYSTEM CONTAINING ANTIPYRINE AND SULFOSALICYLIC ACID

2021 ◽  
Vol 64 (5) ◽  
pp. 19-23
Author(s):  
Mikhail I. Degtev ◽  
Aleksandra A. Yuminova
Keyword(s):  
Aqueous Phase ◽  
Room Temperature ◽  
Photometric Determination ◽  
Sulfosalicylic Acid ◽  
Salting Out ◽  
Maximum Extraction ◽  
Instrumental Methods ◽  
Toxic Organic Solvents ◽  
Nitrate Solutions

The possibilities of an aqueous delaminating system containing antipyrine (AP) and sulfosalicylic acid (SSA) for extracting macro - and microamounts of thorium (IV) were studied. The proposed extraction system eliminates the use of toxic organic solvents. The dependences of the distribution of metal from nitrate solutions between phases on the concentration of reagents, acidity of the medium, the amount of inorganic salting-out agent (NaNO3, NH4NO3, Na2SO4) and the volume of the aqueous phase are determined, and optimal conditions for extraction are found. It is shown that in the organic phase with a volume of 1.6 ml at room temperature, macro-and microamounts of thorium (IV) are extracted by 88 and 90%, respectively. The maximum extraction of the cation is achieved at the ratio of AP: SSA = 2.0 : 1.0 and their concentration, mol/l: 0.6: 0.3, while the acidity of the medium created by nitric acid should be equal to 0.015 mol/l (pHequ. = 1.8-1.9). The extraction of thorium (IV) becomes quantitative if inorganic salts (sodium sulfate, sodium nitrate) are introduced into the AP – SSA – 0,015 mol/l HNO3 – H2O system, which, by reducing the activity of water, increase the concentration of reagents in the aqueous phase. The concentration of salting-out agents should correspond to 1.0 and 2.5 mol/l. A mechanism for the distribution of a mixed thorium (IV) complex containing AP, SSA, nitrate ions, solvated with a salt of antipyrinium sulfosalicylate is proposed. The extract is mixed in any relationship with distilled water, providing the use of various instrumental methods of analysis. A method for extraction-photometric determination of thorium (IV) with a toron indicator has been developed. The limit for the fulfillment of the Bouguer-Lambert-Beer law is established. The apparent coefficient of light absorption is calculated (ε = 1.7∙104).

scholarly journals Extraction of macro quantities of scandium (III) in antipyrine-benzoic acid-water segregate system without the use of organic solvents

2021 ◽  
Vol 11 (2) ◽  
pp. 126-138
Author(s):  
Irina A. Starichenko ◽  
◽  
Mikhail I. Degtev ◽  
Yulia B. Elchischeva ◽  
Pavel V. Melnikov ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Benzoic Acid ◽  
Organic Solvents ◽  
Organic Phase ◽  
Aqueous System ◽  
Optimal Conditions ◽  
Salting Out ◽  
Extraction Capacity ◽  
Maximum Extraction ◽  
Degree Of Extraction

The optimal conditions of separation of aqueous system containing antipyrine, benzoic acid, hydrochloric or nitric acids, inorganic salting-out agents, and water at 85 ° C have been determined. The resulting organic phase contains the antipyrinium benzoate salt, which is a phase former. It is shown that the concentration of hydrochloric and nitric acids in the range of 0,01–0,20 mol/l promotes the stratification of the system, and above 0.4 mol l leads to homogenization. The conditions for the quantitative or maximum extraction of macroquantities of scandium (III) in the studied systems were found and their extraction capacity was determined. Inorganic salting-out agents provide separation even in the presence of 0,5 mol/l hydrochloric or nitric acid, while the degree of extraction of scandium (III) ions is significantly increased.

Extraction of americium with benzyldimethyllaurylammonium nitrate from aqueous nitrate solutions

1979 ◽  
Vol 44 (6) ◽  
pp. 1900-1907 ◽  
Author(s):  
Věra Jedináková ◽  
Jana Cibulková ◽  
Libor Kuča
Keyword(s):  
Organic Solvents ◽  
Organic Phase ◽  
Infrared Spectra ◽  
Distribution Ratio ◽  
Analytical Data ◽  
The Other ◽  
Extraction System ◽  
Salting Out ◽  
Extraction Mechanism ◽  
Nitrate Solutions

The extraction of Am(III) with benzyldimethyllaurylammonium nitrate from acidic nitrate solutions was studied. The effects of the kind and concentration of the salting-out agent, of the organic solvents, and of the concentrations of the other components in the extraction system on the distribution ratio values and applicability of this extracting agent to the separation of americium from lanthanoids are discussed. From the analytical data on the organic phase and from the infrared spectra, the composition of the extractable associates and their extraction mechanism were established.

scholarly journals EXTRACTION OF RARE-EARTH ELEMENTS BY MIXES OF ISOMERS OF TRIBUTYLPHOSPHATE WITH NITRATE TRIALKYLMETHYLAMMONIUM

2018 ◽  
Vol 61 (7) ◽  
pp. 55
Author(s):  
Alexander V. Val'kov ◽  
Nadezhda D. Khmelevskaya
Keyword(s):  
Rare Earth ◽  
Synergistic Effect ◽  
Rare Earth Elements ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Constant Composition ◽  
Salting Out ◽  
Isomolar Series ◽  
Variable Concentration ◽  
Gadolinium Nitrate

Results of studying of extraction of nitrates of rare-earth elements (REE) and trialkylmetylammoniya nitrate (TAMAN) are given by mixes of isomers of tributyl phosphate (TBP). Tri-iso-butylphosphate and tri - sec-butylphosphate are investigated as isomers of normal tributylphosphate. The water phase contained 8 mol/dm3 nitrate of ammonium and 5.10-4 mol/dm3 of neodymium nitrate at рН = 2-3. The content of extractants in isomolar series was varied in the range of 0-0.3 mol/dm3. It was established that synergistic effect decreases in a series of TBP> TIBP> TvtBP. Synergistic effect is calculated as the distribution coefficient relation at extraction by mix of extractants to the sum of coefficients of distribution at extraction by each of extractants. Synergistic effect reaches its maximum value at the ratio: [NPOC] : [TAMAN] = 2 : 1 for TBP and 4-5 : 1 for TiBP, TvtBP, and the absolute value fluctuates within 10-50 at extraction of microconcentration of REE. It is noted that the method of isomolar series is applied incorrectly in many researches with the violation of the fundamental requirements (variable concentration of rare earth metals and acid in the aqueous phase, an assumption of a possibility of simultaneous existence of several solvate, variable concentration of salting-out owing to extraction into the organic phase, the association and polymerization in the organic phase, etc..), which must be followed when using this method. Мultiple saturation method (MSM) is offered for a correct application of the method of isomolar series. The method consists in the fact that the organic phase is saturated repeatedly (5-6 times) with the original aqueous solution until a constant composition of the aqueous phase at all points of  isomolar series. It is possible to believe that the organic phase is responsible for the deviation from the additivity in this case. It was established that synergistic effect tends to unity or virtually disappears in the extraction of REE macroamounts method of ofisomolar series of multiple saturation. It is shown that value of synergistic effect approaches unity at gadolinium nitrate extraction by isomolar mix in the MSM mode. Synergistic effect for a mixture of rare earth elements is close to unity in the extraction of REE mixtures macroamounts of TiBP and TAMAN, and the individual elements are distributed in accordance with the extraction characteristics of each of the extractants alone: synergistic effect for several elements of cerium is greater than one, and yttrium - somewhat less than one. It is suggested that if there is free extragent the formation of mixed solvate may be explained by the steric effect, which disappears at saturation of extracgent.Forcitation:Val'kov A.V., Khmelevskaya N.D. Extraction of rare-earth elements by mixes of isomers of tributylphosphate with nitrate trialkylmethylammonium. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 7. P. 54-60

Solvent extraction of uranium(VI) and thorium(IV) from nitrate media by Cyanex 923

2000 ◽  
Vol 88 (1) ◽  
Author(s):  
S.K. Sahu ◽  
M.L.P. Reddy ◽  
T.R. Ramamohan ◽  
V. Chakravortty
Keyword(s):  
Solvent Extraction ◽  
Metal Ions ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Metal Ion ◽  
Theoretical Methods ◽  
Extraction Behaviour ◽  
Cyanex 923 ◽  
Inorganic Ligands ◽  
Nitrate Solutions

The extraction behaviour of uranium(VI) and thorium(IV) from nitrate solutions has been investigated using Cyanex 923 (TRPO) in xylene as an extractant. The extraction data have been analyzed by both graphical and theoretical methods by taking into account complexation of the metal ion in the aqueous phase with inorganic ligands and all plausible complexes extracted into the organic phase. The results demonstrate that these metal ions are extracted into xylene as Th(NO

A method for selective separation of scandium (III) from yttrium and a number of rare-earth elements for its subsequent determination

2018 ◽  
Vol 84 (11) ◽  
pp. 23-27
Author(s):  
M. I. Degtev ◽  
A. A. Yuminova ◽  
A. S. Maksimov ◽  
A. P. Medvedev
Keyword(s):  
Rare Earth ◽  
Aqueous Phase ◽  
Selective Isolation ◽  
Optimum Ratio ◽  
Extraction Condition ◽  
Sulfosalicylic Acid ◽  
Salting Out ◽  
Subsequent Determination ◽  
Toxic Organic Solvents ◽  
Metal Ions Extraction

The possibility of using an aqueous stratified system of antipyrine — sulfosalicylic acid — water for the selective isolation of scandium macro- and microquantities for subsequent determination is studied. The proposed extraction system eliminates the usage of toxic organic solvents. The organic phase with a volume of 1.2 to 2.0 ml, resulting from delamination of the aqueous phase containing antipyrine and sulfosalicylic acid is analysed to assess the possibility of using such systems for metal ions extraction. Condition necessary for the formation of such a phase were specified: the ratio of the initial components, their concentration, presence of inorganic salting out agents. The optimum ratio of antipyrine to sulfosalicylic acid is 2:1 at concentrations of 0.6 and 0.3 mol/liter in a volume of the aqueous phase of 10 ml. The obtained phase which consists of antipyrinium sulfosalicylate, free antipyrine and water, quantitatively extracts macro- and microquantities of scandium at pH = 1.54. Macro- and microquantities of yttrium, terbium, lanthanum, ytterbium and gadolinium are not extracted under the aforementioned conditions thus providing selective isolation of scandium from the bases containing yttrium, ytterbium, terbium, lanthanum, and gadolinium.

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