Naslov
Sequential separation of Y, Sr, Pu and Am by mixed solvent anion exchange and determination of 89, 90Sr, 241Am and 238, 239Pu

Autori
Grahek, Željko ; Nodilo, Marijana

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstracts of ICRM-LLRMT'12 / - , 2012, P-013

Skup
6th International Conference on Radionuclide Metrology Low-Level Radioactivity Measurement Techniques

Mjesto i datum
Jeju City, Republika Koreja, 17.09.2012. - 21.09.2012

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
89; 90Sr; Alpha emitters; Mixed solvent; Anion exchange; Separation; Electrodeposition; Cherenkov counting

Sažetak
As a rule, the determination of pure alpha and beta emitters is complicated and time-consuming and involves their chemical separation from other elements by ion exchange, extraction, precipitation or in combination of these techniques and subsequent detection on available instruments. Therefore a number of methods have been developed for determination in various kinds of samples, because numerous solutions to the problem are possible. In the last decade, progress was made by simplifying determination methods. It was realized due to of the development of new chromatographic procedures for their separation and development of ICP-MS and low level liquid scintillation counter that enables rapid and simple detection and reliable quantification. However, despite numerous developed procedures for different kinds of samples, procedure for determination of 89, 90Sr is mainly separated from procedures for the determination of other alpha emitters. Therefore, the main purpose of this paper is the development of the procedures for isolation Sr and Pu, Am from complex samples and separation of Y and Sr from alpha emitters in one step by using mixed solvent anion exchange method. It will be shown how strontium and yttrium can be separated from great amount of Na, Ca, Mg and some alpha emitters on the column filled with strong base anion exchanger in nitrate form and alcoholic solution of nitric acid. This separation is possible due to fact that the anion exchange column does not acts as ion exchange column, already, as (ad)sorption column in which separation depends on the power of electrostatic attraction between cations and nitrate ions in the solution and the functional group of exchangers. By changing of nitric acid solution polarity selective sorption of cations and their mutual separation (with alcohol addition) can be achieved. Therefore it will be shown how this type of cation-solution-exchanger interaction can be used for the isolation of Sr, Y, Pu, Am and other alpha emitters from complex samples and mutual separation of Sr and Y from Pu and Am in one step. It should be mentioned that Pu, Th and Am binds from nitric acid on anion exchange column and can be mutually separated by selective elution at the same column so it can be expected that after elution of Sr and Y, americium will be eluted with 8M HNO3, Th with 9M HCl and Pu with 9M HCl-0.1M NH4I. However, in this case separation is directed by classical ion exchange mechanism in which element oxidation state play important role and can prevent binding. This is in contrast with binding from alcoholic solution where Pu oxidation state does not prevent its binding. Therefore it will be shown how Pu can be separated from Am on the same anion exchange column by adjusting of oxidation state on the column. At the base of obtained results, method for the rapid determination of 89, 90Sr by Cherenkov counting and determination of Pu, Am by alpha spectrometry after electrodeposition in soil sample is established. In addition it is well known that preparation of sample source for alpha spectrometry by electrodeposition has advantage over other methods due to simplicity, better homogeneity and resolution. Therefore in this paper, influence of current density and electrolyte composition on electrodeposition efficiency and resolution with emphasis on quality of alpha sources (explored by scanning electron microscopy) will be presented.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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