Volume 5, 2021

Radiochemistry

OXIDATIVE DISSOLUTION OF TRIURANIUM OCTOXIDE IN CARBONATE SOLUTIONS

N.M. Chervyakov, A.V. Boyarintsev, A.V. Andreev, S.I. Stepanov

Pages: 68-74

DOI: 10.21175/RadProc.2021.13

Oxidative dissolution is the key stage of uranium oxide spent nuclear fuel (SNF) reprocessing technology in carbonate media. The ability to quickly and completely dissolve the main component of the SNF matrix - UO 2 in sodium or ammonium carbonate solutions in the presence of hydrogen peroxide at room temperature made it possible to substantiate carbonate media as an alternative to nitric acid media in the SNF reprocessing technology. Before the SNF oxidative dissolution stage, in the CARBEX (CARBonate EXtraction) process, voloxidation (volume oxidation) is carried out. As a result, UO2 completely turns into U3O8. In this work, the dissolution of U3O 8 in sodium carbonate solutions, in the presence of hydrogen peroxide, and sodium percarbonate was studied. The optimal dissolution conditions were determined. With the help of mathematical experimental data processing, the dissolution rates and the apparent activation energy values were calculated.
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N.M. Chervyakov , A.V. Boyarintsev , A.V. Andreev, S.I. Stepanov, "Oxidative dissolution of triuranium octoxide in carbonate solutions",RAD Conf. Proc, vol. 5, 2021, pp. 68-74, http://doi.org/10.21175/RadProc.2021.13