Secondary Reduction of Refractory Metals near the Smooth Cathode during Molten Salt Electrolysis. 1. Derivation of Fundamental Equations for the Process Model

A model of the steady-state process of the refractory metal ion secondary reduction with an alkali or alkaline earth metal formed on a smooth cathode during the electrolysis of molten salt is presented. The secondary reduction is localized near the cathode. The model takes into account the molecular diffusion of the initial components and the thermodynamics of the secondary chemical reaction, the Fick’s first law, the Faraday law, and the Nernst equation. Expressions are obtained for the calculating of concentration profiles, the velocity profile of the secondary reduction reaction inside the diffusion layer, and the secondary reduction current distribution profile over the thickness of the diffusion layer.