氯化物熔盐体系中Gd的电化学行为及提取效率的评估  

Electrochemical Behavior and Extraction Efficiency Evaluation of Gd in Chloride Molten Salt System

作　　者：杨晓南 颜永得 张密林 李星 薛云 韩伟 

机构地区：[1]哈尔滨工程大学材料科学与化学工程学院,超轻材料与表面技术教育部重点实验室,哈尔滨150001 [2]哈尔滨工程大学核安全与仿真技术国防重点学科实验室,哈尔滨150001

出　　处：《物理化学学报》2015年第5期920-926,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(21103033,21101040,91226201,51104050);中国和黑龙江博士后特别资助科学基金(2013T60344,LBH-TZ0411);中央高校基本科研业务经费(HEUCF20151007);黑龙江省普通高等学校和哈尔滨工程大学青年学术骨干支持计划项目(1253G016,HEUCFQ1415)资助~~

摘　　要：研究了773 K时Gd Cl3在Li Cl-KCl熔盐体系中在Mo和Al电极上的电化学行为和热力学特性.利用开路计时电位曲线得到了Gd(III)/Gd(0)体系在723-873 K温度范围的平衡电极电位和表观电极电位.结果表明:平衡电极电位和表观电极电位随着温度的升高而变正.通过吉布斯自由能变进一步计算得到了Gd Cl3在Li Cl-KCl熔盐体系中不同温度下的活度系数.结合稳态极化曲线,求得去极化值,并通过热力学计算,求得773 K时Gd的理论提取效率.在773 K时,在Li Cl-KCl-Gd Cl3体系中,以Al为工作电极在-1.5 V左右通过恒电位电解提取Gd,电解20 h后实际电解提取效率为94.22%.对电解沉积物进行X射线衍射(XRD)分析,检测到了Al3Gd合金相.The electrochemical behavior and thermodynamic properties of Gd Cl3 in LiCl-KCl molten salt system on both Mo and Al electrodes at 773 K were investigated. An open circuit chronopotentiogram was used to determine the equilibrium potentials and standard apparent potentials of the Gd（III）/Gd（0） system in the temperature range 723- 873 K. The results showed that the equilibrium potentials and apparent standard potentials became positive with increasing temperature. The activity coefficients of Gd Cl3 were calculated at different temperatures. The depolarization values were calculated by steady state polarization tests, and the theoretical extraction efficiency was obtained at 773 K. Potentiostatic electrolysis was performed to extract gadolinium from LiCl-KCl-Gd Cl3 molten salt on Al electrodes at-1.5 V. The extraction efficiency was about94.22% after 20 h. The Al3 Gd phase was identified in the deposit by X-ray diffraction（XRD）.

关 键 词：熔盐 吉布斯自由能变 活度系数 提取效率 电解提取 

分 类 号：O646[理学—物理化学]