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1.
M. Kyrš K. Svoboda P. Lhoták J. Alexová 《Journal of Radioanalytical and Nuclear Chemistry》2002,254(3):455-464
Several calixarenes were tested with the aim to find a synergic solvent extraction system with dicarbollide suitable for the extraction of europium from nitric acidic solutions. The best results were obtained with C56H72O12S4 and chlorobenzene. Data on the selectivity and interferences by other nitrates are given. The effect of the concentrations of the extractants and aqueous nitric acid was investigated. Basic data on the kinetics of the extraction reaction are presented. Attempts are described to transform this extraction reaction into an adsorption chromatographic arrangement. 相似文献
2.
V. Jedináková J. Cibulková L. Kuča M. Havranová 《Journal of Radioanalytical and Nuclear Chemistry》1979,51(1):47-54
Benzyldimethyldodecylammonium nitrate and benzyltrioctylammonium nitrate were used for the extraction of Am(III) from aqueous
nitrate solutions. The dependence of the extraction performance for Am(III) on the concentration of nitric acid, the kind
and concentration of salting-out agents in the aqueous phase, and the kind of solvent was investigated. Americium is extracted
by the above quarternary salts as a R4NAm(NO3)4 associate. The extraction of Am(III) is compared with the extraction of lanthanides. The high differences in the distribution
coefficients for lanthanides and americium can be utilized for the separation of lanthanides and americium. 相似文献
3.
Elena V. Kuzovkina Elena A. Lavrinovich Alexander P. Novikov Ekaterina S. Stepanova Maria D. Karavan Igor V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):639-642
Extraction efficiency of uranium and transuranium elements (Np, Pu, Am and Cm) with tert-butylthiacalix[4]arene TCA from carbonate-alkaline solutions is studied and compared with that of europium (III). Plutonium (III, IV) extraction efficiency with TCA is found to be lower comparing with that of trivalent americium and europium. Extraction efficiency of studied radionuclides decreases as following: Am ? Eu ? Pu (III), U(VI), Np (V) > Pu (IV) at pH 12. Carbonate concentration increase in aqueous phase suppresses significantly extraction of all studied radionuclides, except americium. This condition can be used for americium individual recovery from complex radioactive carbonate-alkaline solutions. 相似文献
4.
V. A. Babain M. Yu. Alyapyshev I. A. Novakov B. S. Orlinson E. N. Savel’ev E. A. Shokova A. E. Serebryannikova V. V. Kovalev 《Russian Chemical Bulletin》2007,56(1):115-121
Adamantane di-1,3-carbamoylmethylphosphine oxide derivatives were synthesized. Their efficiency in extraction of americium(III) and europium(III) from nitric acid solutions was shown.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 110–115, January, 2007. 相似文献
5.
Extraction of promethium(III), uranium(VI), plutonium(IV), americium(III), zirconium(IV), ruthenium(III), iron(III) and palladium(II) has been carried out with a mixture of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) and tributyl phosphate (TBP) in dodecane. The effects of nitric acid, TBP and CMPO concentrations on the extraction of these metal ions have been studied. The nature of the species of the above metal ions extracted into the organic phase has been suggested. 相似文献
6.
V. Jedináková J. Cibulková J. Teplý 《Journal of Radioanalytical and Nuclear Chemistry》1979,52(1):69-77
Previously it was found that in the extraction separation on lanthanides and americium from acidic nitrate solutions of nuclear fission products, benzyldimethyldodecylammonium nitrate gives high values of separation coefficients. The change in the extraction capacity of this agent and its solutions in benzene in the extraction of Eu(III) and Am(III) was investigated as a function of the adsorbed dose of ionizing radiation. The slight reduction in the extraction of both metals is caused mainly by the radiolysis products of nitric acid in the organic phase that enter into secondary reactions with both the solvent and the extractant. Comparison of the radiation stability of benzyldimethyldodecylammonium nitrate systems with tertiary amines show that the changes in distribution coefficients in the range of investigated absorbed doses are significantly lower in the former case. The investigated system may be characterized as radiation stable up to about 100 kGy even in the presence of nitric acid. 相似文献
7.
Solven extraction separation of americium(III) from dilute aqueous nitrate media into n-dodecane by bis(2-ethylhexyl)sulfoxide (BESO) has been investigated over a wide range of experimentgal conditioins. Very poor extractablity of Am(III), necessitated the use of calcium nitrate as the salting-out agent. Effects of certain variables such as acidity, extractant concentration, salting-out agent concentration, organic diluents on the metal extraction by BESO have been examined in detail. By increasing the concentration of BESO in organic phase or calcium nitrate in aqueous phase, nearly quantitative extraction of americium even from moderate acidity is accomplished. Slope analyses applied to Am(III) distribution experiments from acidic nitrate solutions indicate predominant formation of the risolvated organic phase complex, Am(NO3)3)·3BESO for which equilibrium constant is found to be, log Kx=1.99. Extraction behavior of Am(III) has also been evlauated in the presence of several water-miscible polar organic solvents to stuy their possible synergistic effects on its extraction. Extractability of americium increased 5 to 10-fold withi increasing conentration of some of these additives, with maximum enhancement being observed in the presence of acetone or acetonitrile. Recovery of BESO from loaded americium is easily obtained using dilute nitric acid as the strippant. 相似文献
8.
Tri-n-octylphosphine sulfide (TOPS) has been investigated as the stationary phase in reversed-phase partition paper Chromatographie separations using nitric or hydrochloric acids as the mobile phase. TOPS has also been studied as an extractant for metal ions. Silver, mercury (II), and palladium (II) were found to have RF values of zero when nitric acid was used as the mobile phase. These same ions were also selectively extracted from aqueous nitric acid solutions. Gold(III), mercury(II), palladium (II), and platinum (IV) were found to have RF values of zero when hydrochloric acid was used as the mobile phase. However, only gold(III) and mercury(II) were extracted from aqueous hydrochloric acid solutions in liquid-liquid extraction systems. Several separations were successfully performed from 1 M nitric acid. 相似文献
9.
Extraction of 241Am and 152Eu from carbonate-alkaline medias with solutions of functionalized calix[4]arenes and their nonmacrocyclic analogs in m-nitrobenzotrifluoride was studied. The dependencies of the Am distribution ratios on pH of the aqueous phase in the range 10 -13.5 and on the position and nature of functional groups in the calixarene core were examined. The composition of extractable solvates of americium with functionalized calix[4]arenes was determined. Thiacalixarenes extract americium more efficiently from alkaline solutions, as compared to calixarenes, demonstrating higher Am/Eu separation factor. Functionalization of the calixarenes improves the Am extraction efficiency and Am/Eu separation factor as well. In the case of thiacalixarenes, functionalization considerably decreases the extraction efficiency and selectivity. 相似文献
10.
V. Jedináková J. Cibulková J. Teplý 《Journal of Radioanalytical and Nuclear Chemistry》1979,50(1-2):69-76
The effect of gamma irradiation on benzene solutions of benzyldibutylamine with cetyl alcohol used for the extraction of europium and americium from nitrate solutions was investigated. The dependence of the distribution coefficient on the dose absorbed either by the whole system or some efficient component was measured. Nitric acid present during irradiation significantly lowers the radiation stability, while benzyldibutylamine and cetyl alcohol appear to be radiostable components. Up to tens of kGy's—the doses expected in an extraction process from highly active solutions—the system seems to be quite stable. 相似文献
11.
Indigenously synthesized extractant, phenyl (octyl) phosphonic acid (POPA) in tri-n-butylphosphate (TBP) and dodecane, has been investigated for the separation of americium from trivalent lanthanides in nitric
acid medium as well as diethylene triaminepentaacetic acid (DTPA) and lactic acid mixture (TALSPEAK medium). Various experimental
parameters like concentration of DTPA, lactic acid, TBP, nitrate ions and pH of the aqueous feed solution have been optimized
to obtain the highest separation factor between americium and europium. Bulk actinide–lanthanide separation reagent, tetra
(ethylhexyl) diglycolamide (TEHDGA), was equilibrated with simulated solution of americium and lanthanides, equivalent in
concentration to the reprocessing waste originating from PHWR spent fuel. DTPA/lactic acid mixture was used to strip the metal
ions from the loaded organic phase and re-extracted into POPA in TBP/dodecane to evaluate the separation factor of individual
lanthanides with respect to americium. Very good separation factors between americium and trivalent lanthanides were obtained. 相似文献
12.
V. Jedináková J. Cibulková J. Teplý M. Novák J. Žilková 《Journal of Radioanalytical and Nuclear Chemistry》1979,51(2):355-362
The radiation stability was investigated of organic phases containing tertiary benzyldialkylamines and quaternary benzyltrialkylammonium
salts which are sultable for the separation of lanthanides and americium from irradiated nuclear fuel. Attention was paid
to changes of the extraction properties in Eu(III) and Am(III) extraction. The influence of the individual components forming
the organic phase (extractant, solvent, solubilizer and nitric acid) on the decrease of the extraction capacity of the organic
phase after irradiation is discussed. The greatest changes in the distribution coefficients DEu and DAm after irradiation were shown for extraction in the presence of nitric acid. As regards the absorbed dose, these systems can
be considered as stable in comparison with organophosphorus extractans. 相似文献
13.
M. I. Kabachnik 《Heteroatom Chemistry》1991,2(1):1-10
This paper is devoted to the steric aspects of the efficiency and selectivity of extractants in the process of extraction of metal cations from acidic aqueous solution into a nonpolar phase. The extraction of uranium, plutonium, americium, and europium by tertiary carbamoylmethyl phosphine oxides and polydiphenylphosphinylmethyl benzenes have been studied. The separation factors of uranium and plutonium from americium are measured. Tertiary carbamoylmethyl phosphine oxides and diphenylphosphinylmethyl benzenes of the ortho type are characterized by unusually high separation factors. The diphenylphosphinylmethyl derivatives of benzene of the meta type do not possess a high selectivity in the process of separation of uranium and plutonium from americium, but are more efficient in extraction of americium. 相似文献
14.
Yasar Arafat Abbasi Akbar Ali Muhammad Haleem Khan Muhammad Mufazzal Saeed Kashif Naeem 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):277-283
The extraction behavior of nalidixic acid (HNA) in CH2Cl2 has been studied for various di- and trivalent metal ions such as Cu(II), Fe(II), Ni(II), Mn(II), Sb(II), Co(II), Sc(III),
Y(III), Nd(III) and Eu(III) from aqueous buffer solutions of pH 1–7 with 0.1 mol dm−3 nalidixic acid in dichloromethane. Separation factors of Sc(III) from these metals has shown that its clean separation is
possible at pH 3.4–4. The parameters affecting the extraction of Sc(III) were optimized. The composition of the extracted
adduct was determined by slope analysis method that came out to be Sc(NA)3. Extraction of Sc(III) was studied in the presence of various cations and anions. Among the anions studied only fluoride,
citrate and oxalate have significant interference whereas, Fe(III) has reduced the extraction to 53% that can be removed by
using ascorbic acid as reducing agent. The proposed extraction system proved good stability up to six extraction-stripping
stages for the extraction of Sc(III). 相似文献
15.
The reactions of various derivatives of chelidamic acid (4-hydroxypyridine-2,6-dicarboxylic acid) with p-tert-butylcalix[4]arene have produced several new mono- and difunctionalized derivatives of the calixarene in which tridentate functional groups suitable for the binding of rare earth metal cations have been incorporated. Single-crystal X-ray structure determinations have been performed on two difunctionalized calixarenes found to adopt different "cone" and "1,2-alternate" conformations, as well as on a complex of europium(III) with the phenoxide form of a monofunctionalized ligand, this structure confirming that charge factors are dominant in determining the site of lanthanide metal binding in these ligands. 相似文献
16.
Elena V. Sharova Oleg I. Artyushin Alexander N. Turanov Vasilii K. Karandashev Svetlana B. Meshkova Zoya M. Topilova Irina L. Odinets 《Central European Journal of Chemistry》2012,10(1):146-156
A ligand system containing three carbamoylmethylphosphine oxide (CMPO) moieties attached to a tripodal platform with a central
nitrogen atom has been synthesized for metal complexation and extraction from neutral and nitric acid solutions. Liquid-liquid
extractions performed for Ln(III), both from neutral and acidic media, show excellent extraction properties which exceeded
those for the known mono- and di-CMPO derivatives as well as the related tripodands. A considerable enhancement of the DLn values was observed in the presence of IL ([bmim][Tf2N]) in the organic phase towards lanthanide ions from 3M HNO3 solutions. The protonation of the central amine nitrogen atom of the ligand 1 in the acidic media provides also the effective extraction of the perrhenate anionic complexes. The europium complexes formed
by mono- and tris-CMPO ligands in the solid state, as well as Eu(III) and Tb(III) complexes generated in solutions, possess
intensive luminescence at 300K 相似文献
17.
V. F. Myasoedov N. P. Molochnikova 《Journal of Radioanalytical and Nuclear Chemistry》1970,6(1):67-73
The effect of agitation time and resin quantity on the sorption of americium, curium and europium from mineral acid solutions, using a chelating resin based on aminopolystyrene and Arsenazo I was determined, and the behaviour of plutonium and fission products was investigated under optimum conditions with respect to the sorption of americium and curium. A procedure is proposed for concentrating americium and curium from dilute solutions, combined with their separation from iron, plutonium and fission products. The procedure consists of sorption on the chelating resin from 0.1–1N mineral acid solutions, washing of the resin with 0.5M oxalic acid and 11N sulfuric acid, and elution of americium and curium with 2M triammonium citrate. 相似文献
18.
D. E. Chirkst O. L. Lobacheva I. V. Berlinskii M. I. Sulimova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(12):2022-2027
The pH values of formation of hydroxo complexes and hydrates in solutions of cerium(III), europium(III), and yttrium salts
were determined by conductometric titration. The instability constants of hydroxo complexes, solubility products of hydroxides,
and Gibbs energies of formation of the compounds specified were calculated. Conclusions about the mechanism of extraction
and ion flotation of these metal cations from aqueous solutions were drawn. 相似文献
19.
Mohammad Reza Yaftian Roqaieh Taheri Dominique Matt 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1225-1230
The extraction of thorium (IV) and europium (III) ions from aqueous nitrate media (1 M nitric acid and sodium nitrate) using six p-tert -butylcalix[4]arene derivatives bearing phosphine oxide units (--CH 2 P(O)Ph 2 ) anchored at the lower rim has been investigated at 25°;C. All ligands display higher extracting properties toward thorium than europium ions. The number and position on the lower rim of the ligating groups play a crucial role in the extraction process, the highest extraction percentages being in each case achieved with the tetra-phosphorylated calixarene. In the presence of sodium nitrate the extraction percentages are considerably higher than those obtained in the presence of nitric acid. 相似文献
20.
A. A. Kopyrin V. D. Murashov V. D. Demidov V. P. Shvedov 《Journal of Radioanalytical and Nuclear Chemistry》1979,51(1):27-46
The extraction distribution and separation of rare earth elements and americium from the concentrated lithium nitrate solution
with solutions of tertiary amines in organic solvents has been studied as a function of the composition and structure of complexones
of the polyaminepolyacetic acid series by a radioactive tracer method. It has been found that diethylenetriaminepentaacetic
acid is suitable for the separation of REE from americium(III). The apparent stability constants for the lanthanide complexes
with EDTA and DTPA in concentrated litium nitrate solutions have been obtained by extraction, pH-metric titration and solubility.
Using these constants, the optimum conditions of separation have been found and the separation factors of REE calculated.
The calculated and experimental values are in good agreement. The optimum conditions for the separation of americium(III)
from REE in a wide range of lanthanide and complexone concentrations (10−1–10−6 M) have been determined. 相似文献