Wednesday, June 20, 2007 - 11:20 AM
The Summit (Boise Centre on the Grove)

Characterization of actinide containing zirconia-magnesia based inert matrix fuel

Kiel S. Holliday and Ken R. Czerwinski. University of Nevada, Las Vegas, Las Vegas, NV

A zirconia-magnesia inert matrix fuel of varied concentrations containing 5% wt/wt UO2 as a PuO2 analog and 2.5% wt/wt Er2O3 as a burnable poison is being examined. Samples are prepared using a precipitation method allowing for less drastic sintering temperatures and times. Crystallographic structure is determined by x-ray diffraction accompanied by Rietveld analysis. Local structure was probed by x-ray absorbance fine structure on both the zirconium K edge and uranium LIII edge. Phase mixing and pore space was visualized by optical microscopy and scanning electron microscopy. Lastly, phase stoichiometry and total concentrations were evaluated by microprobe and x-ray fluorescence respectively. After characterization of the material its dissolution behavior under high temperature water and various acids are evaluated. Samples are taken in situ and concentrations are evaluated by atomic emission spectroscopy. A soxhlet apparatus is used to determine the corrosion resistance of the material gravimetrically. These studies are aimed at explaining the chemical behavior of the material under reactor, reprocessing, and repository conditions.