Electrochemical decladding of used nuclear fuel

Abstract

In this study, an electrochemical method for decladding used nuclear fuel (UNF) was investigated by electrochemically oxidizing pieces of zircaloy in a LiF–NaF–ZrF4 (26-37-37 mol%) salt. Electrochemically decladding UNF allows for zirconium (Zr) to be separated from fission products, such that Zr no longer needs to be stored as high-level waste (HLW). As zircaloy samples were oxidized, both the Zr deposited on the cathode and in the bulk salt were checked for the buildup of elements other than Zr to vet this process. The current efficiency of the system was also found to be over 90% and tested samples of zircaloy were oxidized entirely, showing the current used is not wasted on other reactions than oxidizing zircaloy and that the process works to completion.