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Modelling the Behaviour of Organic Degradation Products

Published online by Cambridge University Press:  26 February 2011

J. E. Cross ,
F. T. Ewart  and
B. F. Greenfield
J. E. Cross
Affiliation:
Chemistry Division, Harwell Laboratory, UKAEA, Oxfordshire, 0X11 ORA, UK.
F. T. Ewart
Affiliation:
Chemistry Division, Harwell Laboratory, UKAEA, Oxfordshire, 0X11 ORA, UK.
B. F. Greenfield
Affiliation:
Chemistry Division, Harwell Laboratory, UKAEA, Oxfordshire, 0X11 ORA, UK.
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Abstract

Results are presented from recent studies at Harwell which show that the degradation products which are formed when certain organic waste materials are exposed to the alkaline conditions typical of a cementitious environment, can enhance the solubility of plutonium, even at pH values as high as 12, by significant factors. Characterisation of the degradation products has been undertaken but the solubility enhancement does not appear to be related to the concentration of any of the major organic species that have been identified in the solutions. While it has not been possible to identify by analysis the organic ligand responsible for the increased solubility of plutonium, the behaviour of D-Saccharic acid does approach the behaviour of the degradation products. The PHREEQE code has been used to simulate the solubility of plutonium in the presence of D-Saccharic acid and other model degradation products, in order to explain the solubility enhancement. The extrapolation of the experimental conditions to the repository is the major objective, but in this work the ability of a model to predict the behaviour of plutonium over a range of experimental conditions has been tested.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 127: Symposium BERLIN – Scientific Basis for Nuclear Waste Management XII , 1988 , 715
Copyright
Copyright © Materials Research Society 1989

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References

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