Dissolution of nuclear materials in aqueous acid solutions

Abstract

The quantitative understanding of the dissolution of nuclear fuel materials is essential for the process design and development of an industrial-scale nuclear fuel reprocessing plant. The main objective of this review article is to analyze the published data related to the dissolution of important nuclear materials, namely, urania, plutonia, thoria, and their oxides in the existing literature. The published results on rate-controlling step and reaction mechanism of dissolution processes are reconciled and reviewed in this work. Clear suggestions are made for future research work for the identification of rate-controlling step. Suggestions are also provided to overcome the shortfalls in the published data for the identification of intrinsic kinetics and mass-transfer rates.

Effect of surface orientation on dissolution rate and surface dynamics of UO2 single crystals in nitric acid

“…This factor reached 370 and 630 for (111) and (110) oriented surfaces, respectively. Such increase of the dissolution rate was already observed for polycrystalline samples of UO2 dissolved in nitric acid media [21,46]. It was attributed to the concomitant increases of the reactive surface area and of the concentration of catalytic species in solution.…”

An isotope dilution mass spectrometry overview: tips and applications for the measurement of radionuclides

“…The irradiated sample rst has to be brought into solution, before spiking can occur. Dissolution of spent fuels for analysis is detailed elsewhere, [216][217][218][219][220][221] but in general terms an irradiated fuel is oen dissolved quantitatively by heating (under reux) under strong acidic conditions over several days inside a shielded hot cell. Only then can spikes be added to an aliquot of the dissolved sample, but crucially before any separations are started.…”

Assay data of spent nuclear fuel: the lab-work behind the numbers

“…There exist slight variations on this dissolution scheme, mainly in terms of molarity of the nitric acid solution and time of heating (Desigan et al, 2019;Momotov et al, 2022). Anyhow, the solubility of SNF has much improved over time as new fabrication methods were developed, specifically for better solubility of SNF in view of later reprocessing schemes.…”