About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Progressive Solutions to Improve the Corrosion Resistance of Nuclear Waste Storage Materials
|
| Presentation Title |
Iron Phosphate Glasses for Molybdenum-Rich Waste Streams |
| Author(s) |
Richard Brow, Jincheng Bai, CW Kim |
| On-Site Speaker (Planned) |
Richard Brow |
| Abstract Scope |
Iron phosphate (IP) glasses are a vitrification option for radioactive waste components with low solubilities in conventional borosilicate melts, including MoO3, found in the secondary waste stream produced by the uranium extraction process (UREX+) for recycling spent nuclear fuel (SNF). The effects of composition and redox conditions on the properties of Na- and Cs-Mo-IP glasses will be reviewed and used to explain their dissolution rates (DR) in water. The most durable glasses are those with O/P > 3.3 and Mo/(Mo+Fe) < 0.22. Less durable glasses prepared under oxidizing conditions have smaller fractions of structurally crosslinking Mo5+OPO4 units, greater fractions of isolated octahedral Mo6+ sites, and greater average P-anion size. These results will then be used to explain the dissolution characteristics of a partially crystallized IP waste form containing 40 wt% Collins-CLT, a simulant of the UREX+ SNF waste stream, and to offer strategies for designing other chemically stable IP glasses. |