Following the electroreduction of uranium dioxide to uranium in LiCl-KCl eutectic in situ using synchrotron radiation

摘要

The electrochemical reduction of uranium dioxide to metallic uranium has been investigated in lithium chloride-potassium chloride eutectic molten salt. Laboratory based electrochemical studies have been coupled with in situ energy dispersive X-ray diffraction, for the first time, to deduce the reduction pathway. No intermediate phases were identified using the X-ray diffraction before, during or after electroreduction to form alpha-uranium. This suggests that the electrochemical reduction occurs via a single, 4-electron-step, process. The rate of formation of a-uranium is seen to decrease during electrolysis and could be a result of a build-up of oxygen anions in the molten salt. Slow transport of O2- ions away from the UO2 working electrode could impede the electrochemical reduction. (C) 2015 The Authors. Published by Elsevier B.V.