Effect of clays and metal containers in retaining Sm3+ and ZrO2+ and the process of reversibility

Knowledge and understanding about radionuclides retention processes on the materials composing the engineered barrier (clay mineral and metallic container waste) are required to ensure the safety and the long-term performance of radioactive waste disposal. Therefore, the present study focuses on the...

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Detalles Bibliográficos
Autores: El Mrabet, Said, Castro Arroyo, Miguel Ángel, Hurtado Bermúdez, Santiago José, Orta Cuevas, María del Mar, Pazos, M. Carolina, Villa Alfageme, María, Alba, María D.
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2014
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/133660
Acceso en línea:https://hdl.handle.net/11441/133660
https://doi.org/10.2138/am.2014.4665
Access Level:acceso abierto
Palabra clave:Actinide
Clay minerals
Geological disposal
Metallic canister
Radionuclide waste
Sorption/desorption
Descripción
Sumario:Knowledge and understanding about radionuclides retention processes on the materials composing the engineered barrier (clay mineral and metallic container waste) are required to ensure the safety and the long-term performance of radioactive waste disposal. Therefore, the present study focuses on the competitiveness of clay and the metallic container in the process of adsorption/desorption of the radionuclides simulators of Am3+ and UO22+. For this purpose, a comparative study of the interaction of samarium (chosen as chemical analog for trivalent americium) and zirconyl (as simulator of uranyl and tetravalent actinides) with both FEBEX bentonite and metallic container, under subcritical conditions, was carried out. The results revealed that the AISI-316L steel container, chemical composition detailed in Table 1, immobilized the high-radioactive waste (HRW), even during the corrosion process. The ZrO2+ was irreversibly adsorbed on the minireactor surface. In the case of samarium SEM/EDX analysis revealed the formation of an insoluble phase of samarium silicate on the container surface. There was no evidence of samarium diffusion through the metallic container. Samarium remained adsorbed by the container also after desorption experiment with water. Therefore, steel canister is actively involved in the HRW immobilization.