Jun 11, 2014
DOE awards Development of Iron Phosphate Waste Forms for Fission Products Waste Streams
Most liquid high-level nuclear waste is currently being immobilized to a solid form as a borosilicate glass by vitrification. However, many nuclear wastes have complex and diverse chemical compositions that reduce their compatibility with borosilicate glass. The current baseline spent nuclear fuel reprocess generates secondary waste streams that generally include large amounts of MoO3 and lanthanides that are poorly soluble in borosilicate glasses and thereby limit the waste loading. New waste forms as alternatives to borosilicate glass are being sought to increase the waste loading while retaining acceptable chemical durability and thus to decrease the total nuclear waste volume required for storage and disposal. The main goal of this program is to develop suitable iron phosphate-based compositions for vitrifying the MoO3-rich waste generated from reprocessed spent nuclear fuel with greater waste loadings than can presently be achieved with borosilicate glass and while retaining chemical durability that meets or exceeds appropriate DOE standards.