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Thermodynamic Modelling of the Effect of Hydroxycarboxylic Acids on the Solubility of Plutonium at High pH

Published online by Cambridge University Press:  01 January 1992

Anthony D Moreton
Anthony D Moreton*
Affiliation:
AEA Decommissioning & Radwaste, B.424.4, Harwell Laboratory, Oxfordshire, UK
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Abstract

A number of the hydroxycarboxylic acids generated by the alkaline degradation of cellulosic wastes under reducing conditions in a cementitious repository can significantly increase the solubility of the actinides at high pH, especially plutonium. The solubility of plutonium at pH 12, in the presence of a range of hydroxycarboxylic acids containing a number of hydroxyl groups and between one and three carboxylate groups, has been modelled using the HARPHRQ code. All the plutonium-organic complexes assumed in the model are based on a stable unit in which a central plutonium ion is bound by four oxygen atoms. The oxygen atoms can be provided either by a deprotonated hydroxyl group on one of the ligands, or by hydroxide ions.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 294: Symposium V – Scientific Basis for Nuclear Waste Management XVI , 1992 , 753
Copyright
Copyright © Materials Research Society 1993

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References

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