摘要
通过循环伏安法、方波伏安法和计时电位法等研究了LiCl-KCl共晶熔盐中ZrCl_4于Mo电极上的电化学行为。探究Zr(Ⅳ)于Mo阴极的还原机理,并计算Zr(Ⅱ)的扩散系数及Zr(Ⅱ)/Zr(0)的表观标准电势。结果表明:Zr(Ⅳ)在Mo阴极还原机理为:Zr(Ⅳ)+2e=Zr(Ⅱ);Zr(Ⅱ)+2e=Zr(0)或Zr(Ⅱ)+e+Cl^-=ZrCl;ZrCl+e=Zr(0)+Cl^-;金属Zr在阳极的氧化过程为:Zr(0)-2e=Zr(Ⅱ)和Zr(Ⅱ)-2e=Zr(Ⅳ)。Zr(Ⅳ)还原为Zr(Ⅱ)和Zr(Ⅱ)还原为Zr(0)均为可逆反应,且还原过程均为扩散控制。LiCl-KCl熔盐中Zr(Ⅱ)于Mo阴极上的扩散系数与温度的关系为:ln D=-6 724/T-2.95,扩散的活化能Ea=55.9kJ/mol。Zr(Ⅱ)/Zr(0)的表观标准电位与温度的关系为:E_(Zr(Ⅱ)/Zr(0))^(Θ*)=-2.695+9.33×10^(-4) T。
In this presentation,the electrochemical behaviors of ZrCl4on the Mo electrode in the LiCl-KCl molten salt have been investigated by various techniques,including cyclic voltammetry,square wave voltammetry,and chronopotentiometry etc.The reduction mechanism of Zr(Ⅳ)on the Mo electrode has been discussed,and the diffusion coefficient of Zr(Ⅱ)and the apparent standard potential of Zr(Ⅱ)/Zr(0)have been calculated.The results show that the reduction mechanism of Zr(Ⅳ)on the Mo cathode is that Zr(Ⅳ)+2e=Zr(Ⅱ);Zr(Ⅱ)+2e=Zr(0)or Zr(Ⅱ)+e+Cl-=ZrCl;ZrCl+e=Zr(0)+Cl-,and the oxidation process of Zr on the anode is:Zr(0)-2e=Zr(Ⅱ)and Zr(Ⅱ)-2e=Zr(Ⅳ).The CV of LiCl-KCl-ZrCl4 indicate that the reduction process Zr(Ⅱ)/Zr(0)is reversible and controlled by diffusion.The dependence of diffusion coefficients of Zr(Ⅱ)in the LiCl-KCl molten salt with temperature is ln D=-6 724/T-2.95and the activation energy is Ea=55.9kJ/mol.The relationship of apparent standard potential of Zr(Ⅱ)/Zr(0)is EΘ*Zr(Ⅱ)/Zr(0)=-2.695+9.33×10-4 T.
作者
肖益群
王有群
林如山
贾艳虹
何辉
XIAO Yi-qun;WANG You-qun;LIN Ru-shan;JIA Yan-hong;HE Hui(China Institute of Atomic Energy,P.O.Box 275(26),Beijing 102413,China)
出处
《核化学与放射化学》
CAS
CSCD
北大核心
2018年第2期100-104,共5页
Journal of Nuclear and Radiochemistry
基金
国家自然科学基金资助项目(No.91226201)
作者简介
肖益群(1989—),男,湖南衡阳人,博士研究生,核燃料循环与材料专业,E-mail:xiaoyiqunpublic@163.com;通信联系人:何辉(1972—),男,陕西武功人,博士,研究员,核化工专业,E-mail:hehui@ciae.ac.cn
