Effect of cement water on UO2 solubility

Research outputpeer-review

1 Scopus citations

Abstract

To assess the stability of spent fuel in the highly alkaline chemical environment of the Belgian Supercontainer design, static leach experiments were performed with depleted UO2 and 238Pu-doped UO2 at different SA/V ratios for 1.5 years in cement waters (11.7<pH < 13.5) at ambient temperature and under argon atmosphere. The influence of the calcium concentration on the uranium release was also investigated. While the ultrafiltered U(IV) concentration was 10-9-10-8 mol. L-1 and independent of the pH, the U(VT) release from the UO2 surface was enhanced by the OH- concentration, leading to soluble U concentrations up to 10-5 mol. L-1 at high SA/V and under the influence of radiolysis. Together with the high Ca concentration, this can lead to the formation of Ca-U(VI) colloids as precursor of Ca-U(VI) secondary phases, decreasing the soluble U concentration. The precipitation of Ca-U secondary phases was however not clearly evidenced by surface analyses.

Original languageEnglish
Title of host publicationScientific Basis for Nuclear Waste Management XXXVII
EditorsLara Duro, Javier Gimenez, Ignasi Casas, Joan de Pablo
PublisherMRS - Materials Research Society
Pages267-273
Number of pages7
Volume1665
ISBN (Electronic)9781605116426
DOIs
StatePublished - 2014
Event37th International Symposium on the Scientific Basis for Nuclear Waste Management - Barcelona
Duration: 29 Sep 20133 Oct 2013

Publication series

NameMaterials Research Society Symposium Proceedings
Volume1665
ISSN (Print)0272-9172

Conference

Conference37th International Symposium on the Scientific Basis for Nuclear Waste Management
Country/TerritorySpain
CityBarcelona
Period2013-09-292013-10-03

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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