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Characterization of a Plutonium-Bearing Zirconolite-Rich Synroc

Published online by Cambridge University Press:  03 September 2012

E. C. Buck
Affiliation:
Argonne National Laboratory, Argonne, IL 60439
B. Ebbinghaus
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94550
A. J. Bakel
Affiliation:
Argonne National Laboratory, Argonne, IL 60439
J. K. Bates
Affiliation:
Argonne National Laboratory, Argonne, IL 60439
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Abstract

A titanate-based ceramic waste form, rich in phases structurally related to zirconolite (CaZrTi2O7), is being developed as a possible method for immobilizing excess plutonium from dismantled nuclear weapons. As part of this program, Lawrence Livermore National Laboratory (LLNL) produced several ceramics that were then characterized at Argonne National Laboratory (ANL). The plutonium-loaded ceramic was found to contain a Pu-Gd zirconolite phase but also contained plutonium titanates, Gd-polymignyte, and a series of other phases. In addition, much of the Pu was remained as PuO2-x. The Pu oxidation state in the zirconolite was determined to be mainly Pu4+, although some Pu3+ was believed to be present.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

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