Abstract
AbstractThe Fukushima Daiichi accident generated degraded nuclear fuel material, mixed with other reactor components, known as molten core-concrete interaction (MCCI) material. Simulant MCCI material was synthesised, excluding highly radioactive fission products, containing depleted U, and incorporating Ce as a surrogate for Pu. Multi-modal µ-focus X-ray analysis revealed the presence of the expected suite of U-Zr-O containing minerals, in addition to crystalline silicate phases CaSiO3, SiO2-cristobalite and Ce-bearing percleveite, (Ce,Nd)2Si2O7. The formation of perclevite resulted from reaction between the U-Zr-O-depleted Ce-Nd-O melt and the silicate (SiO2) melt. It was determined that the majority of U was present as U4+, whereas Ce was observed to be present as Ce3+, consistent with the highly reducing synthesis conditions. A range of Fe-containing phases characterised by different average oxidation states were identified, and it is hypothesised that their formation induced heterogeneity in the local oxygen potential, influencing the oxidation state of Ce.
Funder
RCUK | Engineering and Physical Sciences Research Council
Publisher
Springer Science and Business Media LLC
Subject
Materials Chemistry,Materials Science (miscellaneous),Chemistry (miscellaneous),Ceramics and Composites
Reference51 articles.
1. IAEA. The fukushima daiichi accident: description and context of the accident. Fukushima Daiichi Accid. 1, 1–238 (2015).
2. Burns, P. C., Ewing, R. C. & Navrotsky, A. Nuclear fuel in a reactor accident. Science 335, 1184–1188 (2012).
3. Nuclear Regulation Agency. Benchmark Study of the Accident at the Fukushima Daiichi Nuclear Power Plant (BSAF Project) - Phase I Summary Report, NEA/CSNI/R (2015) 18, 1–56 (2015).
4. Bogatov, S. A. et al. Formation and spread of Chernobyl lavas. Radiochemistry 50, 650–654 (2008).
5. Pazukhin, E. M. Fuel-containing Lavas Of The Chernobyl NPP 4th Block Topography physicochemical properties and formation scenario. Radiochemistry 36, 109–154 (1994).
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