Ultrahigh-Field 95Mo MAS NMR Studies of Model Nuclear Waste Glasses
EMSL Project ID
30210
Abstract
Molybdenum-containing wastes from nuclear power generation require special consideration during immobilization by vitrification. Phase separation and crystallization of a complex mixed-metal molybdate degrades the final glass and restricts the waste-loading capacity in industrial production. The purpose of this investigation is to study the structural environment of molybdenum cations present in model waste glasses using 95Mo NMR. Molybdenum-95 is difficult to probe by NMR because of its low gyromagnetic ratio, low natural abundance and quadrupole moment. In the present case, these problems are exacerbated by the amorphous nature of the materials and the low levels of Mo in the glasses of interest. Despite its difficulties, NMR provides a direct probe of Mo in these materials, and may prove useful in understanding glass structure and phase separation processes. Experiments are proposed on three compositional pairs of glasses: two with different amounts of Cs and one without Cs. These have been prepared at fast and slow quench rates. Lower field experiments clearly show potential to resolve the nature of the crystalline molybdate phases. Project Details
Project type
Limited Scope
Start Date
2008-06-16
End Date
2008-08-16
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
95Mo NMR Study of Crystallization in Model Nuclear Waste Glasses
Scott Kroeker,1 Ian Farnan,2 Sophie Schuller3 and Thierry Advocat4
1Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
2Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, U.K.
3CEA Valrhô Marcoule, DEN/DTCD/SECM/LDMC, BP 17171, 30207 Bagnols/Céze, France
4CEA Saclay, DEN/DANS/DPC/SECR, 91191 Gif-sur-Yvette, France
Materials Research Society proceedings (accepted)