Determination of iron redox in the spinel crystals by 57Fe-Mossbauer spectroscopy
EMSL Project ID
48118
Abstract
The different shapes and sizes of spinel crystals [Fe, Ni, Mn, Zn, Sn][Fe, Cr]2O4 can precipitate from borosilicate glasses during vitrification of high-level radioactive waste (HLW) in the Joule-heated melters.[1,2] They can reach a size of a few hundreds of micrometers and because of their high density ~5.3 g/cm3 settle down fast, forming a thick sludge layer in the spout riser of the melter which prevents the discharge of molten glass into stainless steel canisters. The study of chemical valences and coordination environments of iron cations in spinel-type solid solutions with Mo?ssbauer spectroscopy may shed light on the mechanism of the crystal growth in the borosilicate glasses. The crystal size is the main rate-limiting factor in crystal accumulation; therefore with known mechanism of crystal growth we can mitigate crystal accumulation in the riser of the melter.
Project Details
Project type
Limited Scope
Start Date
2013-07-23
End Date
2013-09-22
Status
Closed
Released Data Link
Team
Principal Investigator