Year
1999
Abstract
A sodalite/glass ceramic waste form has ben developed to immobilize highly radioactive nuclear wastes in chloride form, as part of an electrochemical cleanup process. Simulated waste forms have been fabricated which contain plutonium and are representative of the salt from the elctrometalurgicallurgical process to recover uranium from spent nuclear fuel. X-ray absorption fine structure spectroscopy (XAFS) and x-ray absorption near-edge spectroscopy (XANES) studies were performed to determine the location, oxidation state and form of the plutonium within these waste forms. Plutonium, in the non-fission -element case, was found to segregate as plutonium (IV) oxide with a crystallite size of at least 20 nm. with fission elements present, the crystalline size was about 2nm. No plutonium was observed within the sodalite or glass in the waste form.