Electrochemical Behavior of Tungsten in the (NaCl-KCl-NaF-Na2WO4) Molten Salt

The electrochemical reaction mechanism and the electrocrystallization process of tungsten in the NaCl-KCl-NaF-Na2WO4 molten salt were investigated at 973 K (700 °C) by means of cyclic voltammetry, chronopotentiometry and chronoamperometry technique. The results show that the electrochemical reaction process of tungsten is a quasi-reversible process mix-controlled by ion diffusion rate and electron transport rate; the electrocrystallization process of tungsten is an instantaneous hemispheroid three-dimensional nucleation process; the tungsten ion diffusion coefficient is 2.543×10−5cm·s−1 at the experimental condition of XNaCl:XKCl:XNaF: XNa2WO4= 2:2:1:0.01.