The electrochemical reaction mechanism and electrocrystallization process of tungsten in the NaCl–KCl–NaF–WO3molten salt were investigated at 973 K(700°C)by means of cyclic voltammetry,chronopotentiometry,and chronoamperometry techniques.The results show that the electrochemical reaction process of tungsten in the NaCl–KCl–NaF–WO3molten salt system is a quasireversible process mix-controlled by ion diffusion rate and electron transport rate.Tungsten ion in this system is reduced to W(0)in two steps.The electrocrystallization process of tungsten is found to be an instantaneous,hemispheroid three-dimensional nucleation process and the tungsten ion diffusion coefficient of 2.361 9 10-4cm2s-1is obtained at experimental conditions.
Jie LiXin-Yu ZhangYa-Bin LiuYun-Gang LiRi-Ping Liu
The electrochemical reaction mechanism and electrocrystallization process of Cu on copper electrode in the eutectic NaCl-KCl-CuCl molten salt were investigated by means of cyclic voltammetry, chronopotentiometry and chronoamperometry technique at 710 C. The results show that the electrochemical reaction process of Cu is a quasi-reversible process mix-controlled by Cu + diffusion rate and electron transport rate; the electrochemical reduction mechanism is Cu + +e→Cu; the electrocry stallization process of copper is an instantaneous hemispheroid three-dimensional nucleation process; the Cu + diffusion coefficient is 4.3×10 4 cm 2 ·s 1 under the experimental conditions.