Molybdenum release from high burnup spent nuclear fuel at alkaline and hyperalkaline pH

This work presents experimental data and modelling of the release of Mo from high-burnup spent nuclear fuel (63 MWd/kgU) at two different pH values, 8.4 and 13.2 in air. The release of Mo from SF to the solution is around two orders of magnitude higher at pH = 13.2 than at pH = 8.4. The high Mo rele...

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Detalles Bibliográficos
Autores: García Gómez, Sonia|||0000-0002-9339-5405, Giménez Izquierdo, Francisco Javier|||0000-0003-2094-4458, Casas Pons, Ignasi|||0000-0002-5419-1645, Llorca Piqué, Jordi|||0000-0002-7447-9582, Pablo Ribas, Joan de|||0000-0001-9538-7321, Martínez Torrents, Albert, Clarens Blanco, Frederic, Kokinda, Jakub, Iglesias Pérez, Luis, Serrano Purroy, Daniel
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/402365
Acceso en línea:https://hdl.handle.net/2117/402365
https://dx.doi.org/10.1016/j.net.2023.08.024
Access Level:acceso abierto
Palabra clave:Nuclear fuels
Molybdenum
Spent nuclear fuel
Metallic inclusions
Hyperalkaline conditions
Instant release fraction
X-ray photoelectron spectroscopy
Combustibles nuclears
Molibdè
Àrees temàtiques de la UPC::Enginyeria química
Descripción
Sumario:This work presents experimental data and modelling of the release of Mo from high-burnup spent nuclear fuel (63 MWd/kgU) at two different pH values, 8.4 and 13.2 in air. The release of Mo from SF to the solution is around two orders of magnitude higher at pH = 13.2 than at pH = 8.4. The high Mo release at high pH would indicate that Mo would not be congruently released with uranium and would have an important contribution to the Instant Release Fraction, with a value of 5.3%. Parallel experiments with pure non irradiated Mo(s) and XPS determinations indicated that the faster dissolution at pH = 13.2 could be the consequence of the higher releases from metallic Mo in the fuel through a surface complexation mechanism promoted by the OH- and the oxidation of the metal to Mo(VI) via the formation of intermediate Mo(IV) and Mo(V) species.