NaCl-KCl-NaF-WO_3熔盐体系W^(6+)的电化学行为  

Electrochemical behavior of W^(6+) in NaCl-KCl-NaF-WO_3 molten salt system

作　　者：叶昌美 陈功 韦茗仁 田亚斌 黄晶晶 王昭文 杨少华 YE Changmei;CHEN Gong;WEI Mingren;TIAN Yabin;HUANG Jingjing;WANG Zhaowen;YANG Shaohua(School of Metallurgical and Chemical Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China;School of Metallurgy and Environment,Central South University,Changsha 410006,China)

机构地区：[1]江西理工大学冶金与化学工程学院,江西赣州341000 [2]中南大学冶金与环境工程学院,长沙410006

出　　处：《有色金属科学与工程》2019年第1期20-27,共8页Nonferrous Metals Science and Engineering

基　　金：国家自然科学基金资助项目(51664022);江西省教育厅青年科学基金资助项目(GJJ170544);江西理工大学博士启动基金资助项目(jxxjbs16002)

摘　　要：实验以NaCl-KCl-NaF为电解质体系,WO_3为原料,利用循环伏安法、计时电位法、计时电流法和方波伏安法,研究温度为973 K时钨离子在钨电极上的电化学过程.结果表明:W(Ⅵ)离子的还原过程分2步进行,第1步还原过程为两电子转移,电极反应方程式为W^(6+)+2e^-→W^(4+);第2步还原过程为四电子转移过程,电极反应方程式为W^(4+)+4e-→W,且都为准可逆反应. W(Ⅵ)离子在钨电极上的还原过程受扩散控制,扩散系数为1.05×10^(-9)cm^2/s.The electrochemical reduction mechanism of W6+on the tungsten electrode at 973 K was studied by the methods of cyclic voltammetry,chronopotentiometry,chronoamperometry and square wave voltammetry,and by using NaCl-KCl-NaF and WO3 as molten salt and raw material respectively.The results show that the reduction process of W(VI)ion is carried out in two steps:the first one is a two-electron transfer process,and the electrode reaction equation is W6++2e-→W4+;the second one is a four-electron one,and the electrode reaction equation is W4++4e-→W.The two depositing processes of tungsten ion are both quasi-reversible reactions.The reduction process of W(VI)ion on the tungsten electrode is controlled by diffusion whose coefficient is 1.05×10-9 cm2/s.

关 键 词：NaCl-KCl-NaF-WO3熔盐 电化学行为 扩散系数 

分 类 号：TF841.1[冶金工程—有色金属冶金]