Plutonium and uranium accommodation in pyrochlore oxides

Abstract

Fluorite-related ceramics have attracted considerable attention as potential host materials for the immobilisation of radionuclides. Here we have used computer simulation to investigate the relative solution energies and mechanisms for Pu³⁺, Pu⁴⁺ and U⁴⁺ accommodation in an extensive range of A₂B₂O₇ pyrochlore compounds. Solution is considered from simple oxides and via co-solution mechanisms. Results are discussed in terms of their implications for actinide retention and materials fabrication.

Acknowledgements

Support for this project was provided by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. We wish to acknowledge Dr. Ewan Maddrell for informative discussions.