The dissolution yield, reaction rate constant, and apparent activation energy values of oxidative dissolution of UO_2.25 and U ₃O₈ (obtained in the temperature range 480°C–1200°C) powder samples in 1.0 mol/L NaHCO₃(Na₂CO₃) aqueous solutions at the fractional feeding mode of liquid hydrogen peroxide or crystalline sodium percarbonate (2Na₂CO₃ ⸱3H₂O₂) at various temperatures are estimated, summarized and discussed. The conditions of powdered U₃O₈ samples for complete dissolution in carbonate systems have been defined. The obtained results are fundamental importance for the development and optimization of modes and conditions for alternative carbonate-based systems for voloxidized spent nuclear fuel oxidative dissolution.

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N.M. Chervyakov, A.V. Boyarintsev, I.A. Teplov, S.I. Stepanov, "Kinetic study of the oxidative dissolution of uranium dioxide and triuranium octoxide in carbonate media", RAD Conf. Proc, vol. 6, 2022, pp. 110–118, http://doi.org/10.21175/RadProc.2022.20