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- Author or Editor: A. Zeman x
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Abstract
The solvent extraction of europium(III) with di-n-butylphosphoric {HDBP} and di-(2-ethylhexyl)phosphoric {HDEHP} acids in 3-methyl-1-butanol from 0.1 and 1.0M perchlorate medium {Na(H)ClO4} was studied at pH 1–3. It was found that the composition of the species extracted into the organic phase depended on the concentration of perchlorate anion. In 0.1M Na(H)ClO4 solutions, simple chelates Eu(DBP)3 or Eu(DEHP)3 are extracted while mixed ligand complexes Eu(DBP)2ClO4 or Eu(DEHP)2ClO4 are also extracted from 1.0M Na(H)ClO4 solutions. Compared to the extractions from perchlorate solutions, no such change in the extraction mechanism has been observed in chloride solutions containing up to 1.0M Cl–. The extraction of europium(III) with these extractants into toluene from 0.1M perchlorate or chloride media was studied as well. The extraction species found were identical with those reported in the literature, i.e. {Eu[H(DBP)2]3, Eu[H(DEHP)2]3}. The extraction equilibrium constants were calculated for all complexes.
Abstract
A new extraction reagent-dibutylester of N-/4-antipyryl/-amidophosphoric acid/DBAAP/—has been developed and used for the extraction of divalent mercury into chloroform from mixture of sodium iodide and perchloric acid. It was found that the composition of the species extracted into the organic phase depends on the acidity of the aqueous phase. The solvate HgI2. DBAAP is extracted at low HClO4 concentrations, an ion-pair, /DBAAPH/+.HgI 3 – , is formed and extracted at high concentrations of perchloric acid.
Abstract
A radiometric method for the determination of cadmium based on two-phase isotope exchange has been developed. The sample containing cadmium is shaken in the presence of tartrate with a standard cadmium-115m diethyldithiocarbamate solution in chloroform. From the distribution of the activity between the aqueous and organic phases 0.05–7 
g of cadmium in 5–20 ml sample can be determined.
Abstract
The automated modification of the radioanalytical determination of lead and beryllium using AutoAnalyzer modules has been developed. The method for lead determination is based on a two-phase isotope exchange of lead between the sample solution labelled with212Pb and the standard lead diethyldithiocarbamate solution in carbon tetrachloride. For the determination of beryllium a substoichiometric isotope dilution method using7Be as tracer and acetylacetone in chloroform as extractant was used. As little as 0.02 μg/ml of lead and 2 μg/ml of beryllium can be determined by the methods above. The flow diagrams of the automated procedures are presented.
Abstract
A method is suggested for the determination of submicrogram Cd in quantities by isotope dilution, using substoichiometric extraction into dithizone in chloroform. The applicability of the method was tested in biological samples. Extraction was carried out from a sodium acetate buffer betweenpH 9.7 and 12.0. With amounts of 0.2 μg of Cd, the S.E. was not greater than 0.01 μg. This method is suitable for large scale analysis of trace amounts of Cd in biological materials.
Abstract
A new radioanalytical method has been developed based on homogeneous isotopic exchange in the organic phase. The theory of the method is presented and discussed. This method has been applied for the simple, selective and rapid determination of bismuth based on the isotopic exchange between bismuth diethyldithiocarbamate and bismuth iodide complex labelled with210Bi. As little as 0.01 μg of the metal can be determined.
Abstract
The extraction of cadmium by tri-n-octylamine in benzene and cyclohexane from a mixture of sulphuric acid and potassium bromide has been investigated in detail. The optimum conditions for the extraction and back-extraction of cadmium have been found. The procedure for the concentration of cadmium is described and the separation of cadmium in the presence of more than 30 metals including fission products is presented.
Abstract
The separation of radioactive impurities from the original radioactive material allows to achieve a higher precision of nuclear characteristic measurements of radioactive standards. The different ability of lanthanoides to form amalgams has been used for the separation of145Sm,152+154Eu and169Yb from radioactive impurities. The optimum conditions for electrolysis on mercury electrode followed by the sorption on cellulose powder used for the preparation of weightless standards have been described.
