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Abstract  

The TPE behaviour on the strongly basic anionite Dowex-1×8 in aqueous—alcoholic solutions of lactic, butyric, iso-α-oxybutyric and α-oxyisobutyric acids in a mixture with nitric acid has been investigated. Distribution coefficients and separation factors of TPE have been determined depending on the content of various components of the mixture. High values of separation factors have been obtained for the pair Am-Cm (∼6) using mixtures of α-oxybutyric and nitric acids as eluents in aqueous—alcoholic solutions. The advantages of using macroporous anionites AB-1710P and AB-29P for TPE separation in such solutions are discussed.

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Abstract  

The behaviour of transplutonium and rare-earth elements on anion and cation exchangers in solutions of H3PO4 and H2SO4 in the presence of oxidants (KBrO3, PbO2, (NH4)2S2O8) and in HCl solutions in the presence of reducing agents [Zn(Hg), Eu2+] depending on acid concentration as well as on oxidant content and nature in solution or in resin and other factors has been studied. Effective methods of Bk(IV), Ce(IV), Am(VI), Eu(II) and Md(II) separation from trivalent TPE and REE, as well as continuous methods of isolation of isotopically pure radionuclides250Bk,144Pr by using ion exchangers and inorganic acid solutions have been developed.

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Abstract  

A simple and effective method has been developed for the continuous production of the short-lived isotope Pb as a homolog of element 114 on the principle of a radionuclide generator. The method is based on the initial sorption of 227Ac or 223Ra on a small cation-exchange column, with subsequent “milking” of 211Pb (36.1 m) by a mixture of HCl/CH3OH. The optimum conditions for the repeated separation of 211Pb from radionuclides strongly sorbed by the cation-exchanger (Ac, Th, Ra, Pu, TPE) have been determined. Possibilities of using the 211Pb generator for test experiments on the solution chemistry of element 114 have been shown. Advantages of aqueous alcohol HCl solutions for the isolation of 211Pb (element 114) are discussed.

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Abstract  

The behaviour of transplutonium elements (TPE) on cation and anion exchangers in aqueous alcoholic solutions of chlorides and nitrates of some alkali and alkaline earth metals as depending on different factors: salt concentration, content of alcohol and of acid in the solution as well as the nature of a cation has been studied. The data obtained were used to determine the optimal conditions of concentration of TPE on ion exchangers from solutions containing great quantities of salts. The advantages of the use of aqueous alcoholic solutions of nitric acid in the isolation of TPE from such solutions have been shown.

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Abstract  

The distribution coefficients of californium and other elements between an anion exchange resin and alcohol solutions of nitric acid of different concentrations have been determined. An effective method is suggested for the purification of californium from other elements which are slightly adsorbed when Cf is concentrated on an anion exchanger from 0.5–1.0N solutions of nitric acid containing 95–90% alcohol; Cf is subsequently eluted with a 0.5N HNO3 solution in 85% CH3OH and simultaneously separated from the elements which are strongly adsorbed on the anion exchange resin. Under the chosen conditions the coefficients of californium purification were determined for a number of elements; the values are 5.4·102–1.8·103 for Al, Ca, Fe and ∼103–105 for Am, Pm, Nd, Ce, Pb, Bi and Na, for one cycle.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
L. Guseva
,
G. Tikhomirova
,
G. Buklanov
,
Zen Phar
,
I. Lebedev
,
N. Katargin
, and
B. Myasoedov

Abstract  

Mendelevium-256 was obtained by irradiating of Bk-249 with Ne-22 ions in the external beam of U-300 cyclotron. An efficient ionexchanging method of medelevium isolation and separation from nuclear reaction products have been developed in which a column with cation exchanger and zinc amalgam and 1M HCl solutions as eluents were used. Under these conditions mendelevium has been shown to be reduced and washed out as an alkaline earth element. The ionic radius of Md2+ has been estimated from a correlation of the elution peak positions with ionic radius of several divalent elements. This value was used to calculate the heat of hydration of Md2+ ion.

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Abstract  

On-line chemistry studies of short-lived isotopes of Os and Re, as homologs of 108 (Hs) and 107 (Bh), respectively, produced in the nuclear reactions at the (LNR, Dubna) cyclotron have been carried out. It was shown, that Os and Re are not sorbed on cation exchangers, but very strongly sorbed on anion exchangers from diluted HCl solutions. Re is also retained by a TOPO containing sorbent and may be separated from Os. The possibilities of chemical species and oxidation states investigation of short-lived transactinide elements by continuous chromatography have been shown.

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Abstract  

Ion-exchange behavior of Re and Os as homolgs of Bh and Hs, respectively, has been studied in the sulfuric acid media. The distribution coefficients of 183Re and 185Os as well as of other radionuclides between Dowex-50 and H2SO4 solutions were determined as a function of the acid concentration. It was shown, that cation-exchange column may be used for the separation of Os, Re and W from elements of III group, whereas anion-exchange column for their concentration from diluted sulfuric acid solutions. The 0.05M H2SO4 was used for continuous on-line separation of short-lived Os isotopes produced in the nuclear reactions: nat.Dy(20Ne, xn)Os. Radionuclides of Os, Re and W were strongly sorbed on anion-exchange column only.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Z. Szeglowski
,
H. Bruchertseifer
,
V. Brudanin
,
G. Buklanov
,
O. Constantinescu
,
Dinh Thi Lien
,
V. Domanov
,
L. Guseva
,
M. Hussonnois
,
G. Tikhomirova
,
I. Zvara
, and
Yu. Oganessian

Abstract  

The short-lived isotopes of W and their descendants have been isolated from the products of the bombardment of144Sm with24Mg by a fast continuous ion-exchange method, using HF solution media. The feasibility of this method for isolation of element 106 is discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
D. Schumann
,
R. Dressler
,
St. Taut
,
H. Nitsche
,
Z. Szeglowski
,
B. Kubica
,
L. Guseva
,
G. Tikhomirova
,
A. Yakushev
,
O. Constantinescu
,
V. Domanov
,
M. Constantinescu
,
Dinh Lien
,
Yu. Oganessian
,
V. Brudanin
,
I. Zvara
, and
H. Bruchertseifer

Abstract  

The title goal was achieved using a DOWEX 50Wx8 cation exchange column saturated with La(OH)3 and ammonia solution as eluent. Hf, Ta and Lu were adsorbed on this column, whereas W remained in the solution. This chemical system may be used for fast on-line separations of element 106.

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