Journal of Nuclear Fuel Cycle and Waste Technology

Pyrochemical processing and molten-salt reactors have recently garnered significant attention as they are promising options for future nuclear technologies, such as those for recycling spent nuclear fuels and the next generation of nuclear reactors. Both of these technologies require the use of high-temperature molten salt. To implement these technologies, one must understand the electrochemical behavior of fission products in molten salts, lanthanides, and actinides. In this study, a rotating-disk-electrode (RDE) measurement system for high-temperature molten salts is constructed and tested by investigating the electrochemical reactions of Sm³⁺ in LiCl–KCl melts. The results show that the reduction of Sm³⁺ presents the Levich behavior in LiCl–KCl melts. Using the RDE system, not only is the diffusion-layer thickness of Sm³⁺ measured in high-temperature molten salts but also various electrochemical parameters for Sm³⁺ in LiCl–KCl melts, including the diffusion coefficient, Tafel slope, and exchange current density, are determined.

Keywords

Pyrochemical processing, LiCl−KCl, Rotating disk electrode, Samarium, Tafel slope, Exchange current density