铝电解低温电解质体系的研究现状

Research Status on the Low Temperature Electrolyte System for Aluminum Electrolysis

分析了不同电解质组成对铝电解质体系(主要包含NaF-AlF3、KF-AlF3和NaF-KF-AlF3体系)的初晶温度、氧化铝溶解度及电导率等物理化学性质的影响。指出在低温条件下NaF-AlF3电解体系表现出氧化铝溶解性能较差的缺点;KF-AlF3体系相较于NaF-AlF3体系具有较好的氧化铝溶解性能,但电导率较低,且电解原料中含有钠,随着电解的进行,钠在电解质中不断累积,导致该体系不可避免地变为NaF-KF-AlF3体系;NaF-KF-AlF3体系具有较低的初晶温度,良好的氧化铝溶解性能和电导率,还可以解决钠在电解质中累积带来的问题。因此,NaF-KF-AlF3体系在低温铝电解上是比较有希望得到工业应用的体系。此外,还着重综述了NaF-KF-AlF3体系的研究进展,并探讨了该体系存在的问题及今后的发展方向。

The effects of different electrolyte compositions on the physical and chemical properties such as liquids temperature,alumina solubility and electrical conductivity of aluminum electrolyte systems(mainly including NaF-AlF3,KF-AlF3 and NaF-KF-AlF3 system)were analyzed.It is pointed out that the NaF-AlF3 electrolysis system exhibits the disadvantage of poor solubility of alumina under low temperature conditions.The KF-AlF3 system has better alumina solubility than the NaF-AlF3 system,but the conductivity of the system is lower,and the electrolysis raw material contains sodium,as electrolysis progresses,sodium accumulates in the electrolyte,causes the system to inevitably become NaF-KF-AlF3 system.The NaF-KF-AlF3 system has lower liquids temperature,better alumina solubility and conductivity,and it can also solve the problems caused by the accumulation of sodium in the electrolyte.Therefore,the NaF-KF-AlF3 system is a promising system for industrial applications in low temperature aluminum electrolysis.In addition,the research progress of NaF-KF-AlF3 system is also reviewed,the problems of the system and the future development direction are discussed.