氯化镁电解阴极过程机理及液镁析出状态的研究
来源期刊：中南大学学报(自然科学版)1994年第2期
论文作者：张永健 罗亮明
文章页码：176 - 181
关键词：熔盐电解; 氯化镁电解; 电化学成核过程; 液镁形貌
Key words：molten saIts electrolysis; electrolysis of magnesium chloride; electrochemical nu-cleation; morphology of liquid magnesium
摘 要：在700～750℃的温度条件下,应用电化学稳态技术和暂态技术,对氯化镁电解镁离子的放电过程和液镁成核过程进行了研究.在此基础上考察了工艺条件对液镁析出状态的影响.研究表明：镁的析出过程是包含两个电子的受扩散过程控制的简单反应;液镁析出的相过程为三维瞬时成核过程.导出了成核速度和核心生长速度表达式.电解质氯化镁浓度、电流密度、电解温度和电极材料均能影响液镁析出状态.
Abstract: Studies have been made of the process of magnesium ions discharge and the nucleationand growth of liquid magnesium in magnesium chloride electrolysis at 700～750℃ by use ofelectrochemical steady and transient techniques. The cathodic overpotential of magnesium islow and mainly attributed to concentration polarization. The deposition process of magnesiumis a diffusion controlled simple reaction involving two electron transfer. Nucleation plays asignificant role at the beginning and it is an instantaneous process followed by three-dimen-tional growth.The N-η and I-t dependences for the formation and growth of nuclei are giv-en. The effect of temperature,current density,MgCl2 concentration and cathode material onthe morphology of liquid magnesium was also studied.The path of improving the adheringstate of liquid magnesium to cathode is analyzed in terms of cathode process mechanism.
