Electrochemical Reduction Of Uranium (IV) Oxide And Its Analogues In Molten Lithium Chloride-Potassium Chloride Eutectic

Spent nuclear fuel reprocessing has traditionally utilized liquid-liquid (LLE) extraction techniques, such as the PUREX process. Whilst these processes are well established, they can produce product streams of weapons grade material. Today, the spent fuel reprocessing industry is developing new techniques that will allow for proliferation resistant re-processing methods in closed loop nuclear fuel cycles. Direct electrochemical reduction of the spent oxide fuels coupled with selective electro-refining is one such technique. In this work, the authors have investigated the electrochemical reduction of uranium (IV) oxide and its analogues in the molten lithium chloride-potassium chloride eutectic. The purpose of this work is to ascertain the necessary conditions for the reduction to proceed and to reveal any limitations of the process. Electrochemical techniques, such as cyclic voltammetry and chronoamperometry have been used to investigate the electrochemical reduction. In addition, coupled microstructural characterisation and chemical analysis have been used to ascertain how changes in the microstructure affect the electrochemical reaction pathway as it is proceeding.