Study of Extraction of Transactinide Homologues Pavel

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F22%3A00369468" target="_blank" >RIV/68407700:21340/22:00369468 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Study of Extraction of Transactinide Homologues Pavel

Original language description

The dissertation deals with a complex topic of liquid-liquid extraction of group 6 elements from the seaborgium point of view. The topic can be divided into three main areas of focus: exploring the possibility of employing industrial grade extraction agent Cyanex 600 for extraction of group 6 elements from nitric acid solutions, describing the system’s behaviour in sub-minute continuous extraction process using microfluidic technique, and linking the microfluidic extraction to cyclotron-production of radionuclides and their subsequent transport via the gas-jet transport system developed at Oslo Cyclotron Laboratory. The Cyanex 600/HNO3 system characterization revealed similarity with extraction mechanism of organophosphorus acids. The mechanism of Mo extraction with Cyanex 600 was established and apparent extraction constants Kex of three pH-dependent extraction sub-processes were calculated. Although it was not proved with absolute certainty that the mechanism for W and Mo is the same, results for W extraction were determined using the same mechanism. In addition, the data analysis provided value of apparent dimerization constant Kdim of Cyanex 600 in kerosene. Based on the value of Kdim, and the mechanism itself, it was revealed that main component of Cyanex 600 might not be Cyanex 272 as anticipated, but rather its dithio-derivate Cyanex 301. However, results suggest Cyanex 600 could be a mixture of extractants, which was expected. All results in this area are unique as basically no literature data on Cyanex 600 behaviour are available. Microfluidic system for fast extraction was successfully employed, and yielded aqueous-to-organic overall volumetric mass transfer coefficients that quantify kinetic performance of the system under given conditions. The acidity region between 0.1 and 0.01 mol L-1 was identified as the most promising for potential Sg application for its fastest kinetics and extraction efficiency for both Mo and W. Furthermore, two microfluidic mixing techniques were compared – extraction in a capillary (inner diameter of 250 μm) and in a micromixer chip. Both were shown to have almost identical kinetic performance. Data obtained in this area are also new. Finally, the PILS system, that was originally developed as an aerosol sampler for ion chromatography, was tested as a linking segment between the Oslo gas-jet transport system and microfluidic extraction system. The idea to link PILS with a GJT system is an original one and it has not been realized before in the field of SHE research. Overall yield of 18 % was obtained for the processes of gas-jet transport and PILS conversion into the aqueous phase. In addition, using PILS provided huge gas-into-liquid concentration factor of 4600 (for the yield of 18 %). To further improve the whole system, new recoil-transfer chamber with remote robotic target-switching system (called MARGE) was developed and has been utilized since 2021. Due to its remote and autonomous nature, the MARGE system allows for much more efficient use of cyclotron beam time, and increases radiation safety of the personnel as their physical presence in the cyclotron vault is now rarely required.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

10402 - Inorganic and nuclear chemistry

Project

<a href="/en/project/EF16_019%2F0000778" target="_blank" >EF16_019/0000778: Center for advanced applied science</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů