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The present article gives a comparative account of the efficiency of carrier-free 90Y separation from 90Sr by solvent extraction, flat sheet-supported liquid membrane (FSSLM) and hollow fiber-supported liquid membrane (HFSLM) methods using bis(2-ethylhexyl) phosphonic acid (PC88A) as the carrier extractant. The major focus of this work has been to develop the HFSLM method for the separation of Y(III) on a relatively large scale. The feed and receiver phase conditions were optimized by carrying out batch solvent-extraction studies. The extraction of Sr(II) by PC88A was negligible in the acidity range of 0.01–3 M HNO3, whereas the extraction of Y(III) was significantly large at lower acidity (≤0.1 M HNO3) with a separation factor (SF = DY/DSr) of 8.5 × 104. HFSLM studies suggested selective and efficient transport of Y(III) into 3 M HNO3 from a feed solution containing a mixture of Y(III) and Sr(II) at 0.1 M HNO3. On the other hand, transport of Sr(II) was negligible in the receiver phase. The purity of the...

Solvent extraction studies on Sr2+ and Y3+ are carried out from varying concentrations (0.01–6.0 M) of nitric acid using di-(2-ethylhexyl)phosphoric acid (D2EHPA) as extractant. Extraction of yttrium is observed to be higher than that of strontium at all the acidities and is found to increase substantially with decreasing concentration of nitric acid. Practically negligible extraction (D 90%) from 90Sr is obtained in 6 h, when the concentration of nitric acid in feed is kept at 1.0 M and that of receiving phase is maintained at 4.0 M. 20% D2EHPA in n-dodecane is found to be the optimum carrier concentration for the efficient transport of 90Y in SLM ...

Solvent extraction studies of Y3+ and Sr2+ with 2‐ethylhexyl 2‐ethylhexyl phosphonic acid (KSM‐17) and octyl(phenyl)‐N,N‐diisobutylcarbamoylmethylphosphine oxide (CMPO) are carried out from aqueous media containing a wide range of nitric acid and other potential reagents to arrive at the operating conditions for the selective transport of 90Y using supported liquid membrane (SLM) containing these reagents as carriers. Since the transport data of 90Y using single cell SLM with KSM‐17 was available from our earlier experiments, single cell transport studies with CMPO carrier are only carried out to optimize the strippant phase. Transport studies with pure 90Y is carried out using a transport cell with two SLMs one with KSM‐17 and the other CMPO carriers to optimize the transport parameters. Based on these data the development of a two stage SLM system for the generation of carrier free 90Y from 90Sr source is described. The procedure described is amenable for automation and scale up.

The various methods of separation of carrier free lanthanide elements have been briefly described.

The various methods for separation of carrier free radionuclides of second transition series elements from the bulk target matrix has been discussed in brief.

Interval free flow zone electrophoresis is a new mode of free flow zone electrophoresis (FFZE), which facilitates purification of proteins and other molecular substances at very high resolution. It can be performed in the commercially available free flow electrophoresis (FFE) apparatus Octopus. The specimens are loaded and unloaded as usual with the help of a thin buffer film flowing between the two glass plates of the FFE. However, as long as electrical current is applied to a specimen, the medium flow is turned off and conditions of static column electrophoresis are simulated within the FFE device. Thereby electrohydrodynamic flow effects, which widen the sample bands migrating within the electric field, are eliminated while optimal heat removal from the thin buffer film is still possible and a sophisticated technique of harvesting of fractions remains available. Thus interval FFZE offers a gentle preparative method for purification of many kinds of charged molecular species such as proteins or...

The sorption behavior of 99mTc on zinc dust was studied as a function of pH. Optimum conditions have been found for the preconcentration of traces of Tc by zinc. The influence of surface-active substances and of complexing agents on the sorption of trace amounts of Tc on zinc dust has been also studied.

A very simple procedure for the radiochemical separation of carrier-free RaE (210B) from RaD (210Pb) has been developed. RaE as sulfate was adsorbed in powdered alumina column, which was later quantitatively washed out with hot cone HNO3. The radiochemical purity of RaE had been proved by studying the β-decay half-life of the isotope.

Preparation de 228 Ra a partir de la desintegration nucleaire du thorium issu du nitrate de thorium. Il est separe des autres produits de filiation au moyen de techniques d'extraction par solvant et d'echange cationique

Methods are described: a to iodinate glucagon with carrier-free 125I using Iodogen© as the oxidizing agent and, b to purify from the reaction medium a mixture of [125I-Tyr10] monoiodoglucagon and [125I-Tyr13] monoiodoglucagon using reverse phase high pressure liquid chromatography (HPLC).

Routine production process for radioisotope 32P on a large scale is described. As target material elementary sulphur irraidated in reactor EWA is used. 32P in the form of ortophosphoric acid carrie...

An efficient and simple method is presented for the radiochemical separation of 95Zr from 95Nb in a carrier-free state. 95Zr is desorbed quantitatively from the MnO2 column using a 3 M HNO3 + 0.05 M HF solution. By following the recommended procedure, a decontamination factor higher than 105 is achieved. The radionuclidic purity of the separated 95Zr has been ascertained by gamma-ray energy measurements as well as by a radiochemical method. The entire procedure takes less than 20 min.

Stoichiometric stability constants of the thallium (I) sulphate complex [Tl(SO4)]− have been determined by measurements of the 201Tl.Tl(I) ion mobility at 298.1 (1) K in solutions of Na2SO4/Na(H)ClO4, μ = 0.1, pH ≦ 4, and Na2SO4/H2SO4, 0.1 ≦ μ ≦ 0.48, pH 2–2.5. The thermodynamic stability constant of this complex anion of = 15.7(1.0) 1 · mol−1 has been calculated on the basis of experimental data.

Carrier free radioactive 54Mn and 59Fe enjoy favoured position in industrial, agricultural and medical applications [1]. The main methods used for their isolation from suitable irradiated targets are mainly based on solvent extraction [2] or ion exchange [3].