New formulation for reduction potentials of (Cu, Ni, Al, Zn)–lanthanide alloys – Implications for electrolysis-based pyroprocessing of spent nuclear fuel

Abstract In this work, the electrochemical behavior of lanthanides (except promethium) on several active cathodes in LiCl–KCl molten salts was investigated. We have discovered that the reduction potentials of lanthanide alloys present a “bimodal effect”. A numerical model was established based on the result of multiple linear regression analyses, which indicates that the reduction potentials are correlated with differences in atomic radii and differences in electronegativity. Employing the fitted formulae, which provide a preliminary model of the behavior of these elements in electrolysis-based pyroprocessing, the electrochemistry of both lanthanides and actinides on active metal cathodes could be reasonably estimated.