XPS study of external α-radiolytic oxidation of UO2 in the presence of argon or hydrogen

JOURNAL OF NUCLEAR MATERIALS

卷:543

Article

Hansson, N. L.¹  Tam, P. L.²  Ekberg, C.¹  Spahiu, K.^1,3 

[1] Chalmers Univ Technol, Nucl Chem Ind Mat Recycling, SE-41296 Gothenburg, Sweden

[2] Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden

[3] Swedish Nucl Fuel & Waste Management Co, SE-10124 Stockholm, Sweden

关键词: UO2;    radiolysis;    hydrogen effect;    oxidation;    dissolution;    x-ray photoelectron spectroscopy;   

DOI  :  10.1016/j.jnucmat.2020.152604

来源: Elsevier

【 摘 要 】

UO2 pellets exposed to 1.85 MBq and 3.30 MBq Am-241 sources with a 30 mu m separation in solution were studied under Ar and H-2 atmospheres. The 1.85 MBq Am-241 source was shown to have a too low radiolytic production to cause any measurable change in UO2 surface oxidation state. However, a significant oxidation was observed after exposure to the 3.30 MBq source under Ar atmosphere through the production of U(V), as seen from the U4f(7/2)-peak deconvolution and valence band peak analysis. The H-2 atmosphere was shown to suppress the oxidation of the UO2 pellet surface as well as the dissolution in both Milli-Q and NaHCO3 solutions. The dissolved uranium concentration was reduced by a factor 10 under H-2 atmosphere as compared to the Ar atmosphere experiments. (C) 2020 The Authors. Published by Elsevier B.V.

【 授权许可】

Free