Authors:E. Tereshatov, H. Bruchertseifer, M. Voronyuk, G. Starodub, O. Petrushkin, and S. Dmitriev
Isocratic anion exchange separations of Group V elements from solutions containing HF have been considered for the development
of Db aqueous phase chemistry experiments. Separation of Nb/Ta from an HF/NH4F system has been demonstrated but has limited utility due to interferences with alpha and spontaneous fission (SF) source
preparation. The physical parameters associated with ion exchange chromatography have been optimized for the separation and
sequential isolation of Pa, Nb and Ta from mixed HF/HNO3 solutions. A suitable procedure incorporating a series of successive chemical separation techniques, i.e. precipitation and
ion exchange chromatography, has been suggested for off-line Db characterization studies.
Authors:S. Usuda, N. Shinohara, H. Yoshikawa, S. Ichikawa, and T. Suzuki
Anion exchange separation of250Fm (30 m) synthesized by the12C+242Pu and16O+238U reactions has been investigated with mineral acid-methyl alcohol mixed media at elevated temperature. Fermium was chromatographically separated from the other transplutonium elements, the target materials and an Al catcher foil by anion exchange with mixtures of nitric acid and methyl alcohol. By use of the mixed media of hydrochloric acid and methyl alcohol, Fm together with Cf was separated from Al, Am, Cm, Pu, U and major fission products. The separation systems are suitable for rapid separation and immediate alpha-counting source preparation of Fm.
Anion exchange separation of Ga-In on Dowex 1 resins of 2, 4, 8, and 10 nominal cross-linkings, respectively, was investigated
at tracer loadings. The influence of temperature on the exchange reaction was also studied on the different resins. Separation
factors, plate heights, and resolutions for the two peaks were calculated from the elution curves. Best separations were achieved
with Dowex 1X4 due to the most promising values for both plate height and resolution. It was also found that the separation
factors as well as the plate heights decreased with growing temperature.
Eskişehir-Beylikahir ore contains rare earth elements (REE) and thorium as bastnaesite mixed with barite, calcite and fluorite
and small amounts of uranium. The mineralogical composition and Th, U, REE contents of the ore samples taken from different
sectors of the same region show important variations. For the spectrophotometric determination of Th and U in the ore, successive
anion-exchange and solvent extraction procedures are carried out to separate U and Th from each other and from accompanying
interfering elements. The accuracy and precision of the method is demonstrated by intercomparison of the thorium standard
reference samples S-14, S-15 and S-16 of IAEA. In all cases very good agreement was obtained.
Authors:S. Usuda, H. Yoshikawa, M. Magara, and Y. Hatsukawa
Adsorption behaviour of Bk/III/ on anion-exchange resin in mineral acid-methyl alcohol mixtures has been investigated. Berkelium was successively separated with a HCl–CH3OH mixture at elevated temperatures within 5 min from an Al catcher foil collecting the recoil products of the4He+241Am reaction. The counting source of Bk was immediately prepared for alpha- and X-ray spectrum measurements. Rapid separation of Bk from Ce was also performed by the use of a HNO3–CH3OH mixture.
The possibilities of separation of rare earths in the system: Dowex 1—aq. H3PO4 have been investigated. It has been found that in orthophosphoric acid solution these elements form anionic phosphate complexes.
The selectivity coefficients for the anion exchange reaction of Tm, Yb, Lu and Sc complexes have been obtained from the elution
curves for the temperature range of 5–85°C. From these data the values of free energy, enthalpy and entropy change for the
ion exchange reactions in question have been calculated. The effect of temperature and of resin cross-linking on the column
performance has been evaluated.
The microscale liquid chromatograph used in the present work is as follows: injection volume of sample 0.2–0.9 μl; column
0.5 mm i.d x 12–59 mm; connecting tube between column and detection cell 0.25 or 0.5 mm i.d. x 20 mm; detection cell 0.25
or 0.5 mm i.d. x 8 mm. The high performance anion exchange resin, TSK LS-222, was loadd in the column, and applied to the
separation of halide ions. Three halides, Cl−, Br− and I− have been separated with a column of 59 mm length within 19 min, using only 152 μl of 1.5N sodium nitrate-acetone (1:1) mixture
as carrier solution. When the element of interest is only iodine, it could be separated from the other halides with a column
of 12 mm length within 4.5 min. Some fundamental studies for HETP and capacity factor are presented.
Authors:G. Rizvi, N. Chaudhuri, R. Rastogi, and S. Patil
A procedure has been developed for quantitative separation of yttrium from uranium by anion exchange from nearly saturated
NH4Cl solution in 0–2N HCl medium. Apparently no organic matter is leached out during the separation as yttrium could be determined
by EDTA titration without resorting to fuming with perchloric acid before titration. The precision obtained in the analysis
of yttrium in a mixture containing about 12 mg of yttrium and about 300 mg of uranium was ±0.3% (27 determinations).
On Biorad Ag-1X8 anion-exchange resin (200–400 mesh), Pd and Pt may be separated from one another by elution with 0.2M HClO4, and 5M HClO4, respectively. If present, Au may be retained by making the elutriants 0.003M in HCl. Alternatively, reduction by H2SO3 enables elution of Pt2+ with 6M HCl before recovery of Pd2+ with 0.2M HClO4·Ir4+ is reduced to Ir3+ by H2SO3 and may be eluted ahead of Pt2+ by 2M HCl.
Ground water samples obtained from West Bengal, India were analyzed for total arsenic and its inorganic species contents by
instrumental neutron activation analysis (INAA). Two anion exchange separation methods using Dowex 1X8 in chloride and acetate
forms were standardized for the speciation of As(III) and As(V) using radiotracers. The method by Dowex 1X8 in the acetate
form was validated using synthetic mixtures of As(III) and As(V), and applied to water samples; the species concentrations
were determined by INAA. The accuracy of the INAA method was evaluated by analyzing the NRCC CRM DORM-2 for total arsenic.