Itsuhachiro Hataye

Solvent extraction study on the hydrolysis of tracer concentration of Po(IV) in chloride solutions

Abstract The hydrolysis and chlorocomplex formation of Po(IV) was investigated through solvent extraction with dithizone-carbon tetrachloride solutions. In a 1.0 M (H,Na)Cl solution, a tracer concentration of Po(IV) (about 10 −12 M) was found to exist as; Po(OH) 2 Cl 4 2− , Po(OH) 2 Cl 3.7 1.7− , Po(OH) 2 Cl 3.5 1.5− , Po(OH) 2.1 Cl 2.0 − and Po(OH) 4 for −log[H + ] = 0, 1, 2, 3 and 6, respectively. The constants of successive hydrolysis, β 1 = [Po(OH) 3 Cl n 1− n ][Po(OH 4 ] −1 [H + ] −1 [Cl −1 ] − n and β 2 = [Po(OH) 2 Cl n 2− n ][Po(OH) 4 ] −1 [H + ] −2 [Cl − ] − n were calculated from the distribution ratios obtained, giving the results; log β 1 = 4.6 ± 0.3 and log β 2 = 8.7 ± 0.3. The chemical composition of extracted species was probably PoCl 2 (HDz) 2 , Po(OH)Cl(HDz) 2 and Po(OH) 2 (HDz) 2 .

SEPARATION OF POLONIUM SPECIES IN NITRATE SOLUTIONS BY PAPER CHROMATOGRAPHY

Ascending paper chromatography using Toyo No. 50 paper and n-BuOH saturated with 1.0M HNO3 as a developing solvent, was useful to examine the separation of polonium species in (H,NH4)NO3 solutions. A neutral mononuclear species (Po(OH)4) appeared in the vicinity of Rf=0.6. The Rf values of each species decreased depending on the increasing cationic tendency and polymerization of the polonium species.

A cation-exchange study of stability constants of complexes formed between bismuth/III/ and nitrate or chloride ions

A cation-exchange method was used for determining the stability constants of complexes formed between Bi/III/, present in tracer concentrations /ca. 10−11M Bi/, and nitrate ion or chloride ion in 1.OM H/ClO4, NO3/ or 1.OM H/Cl, ClO4/ solutions, respectively. The successive formation constants were calculated using the distribution data. The resulting 1g β1, 1g β2, and 1g β3 values were 0.74, 1.22, and 1.54 for 1.OM H/ClO4, NO3/ solutions, and 2.36, 3.61, and 4.95 for 1.OM H/Cl, ClO4/ solutions, respectively.

Mutual separation of210Po,210Bi, and210Pb with solvent extraction using copper dithizonate −CCl4 and dithizone −CCl4 solutions

Displacement-extraction of tracer concentrations of210Po in 1.0M (H, Na)NO3 solutions has been studied by using copper dithizonate−CCl4 solutions. Furthermore, based on the results of the displacement-extraction of polonium, a mixture of210Po,210Bi, and210Pb of tracer concentrations in 1.0M (H, Na)NO3 solutions could be satisfactorily separated with successive extractions by copper dithizonate−CCl4 and dithizone−CCl4 solutions in acidic conditions.