KF含量对铝电解质物理化学性质的影响研究

Study on effects of KF content on physical and chemical properties of aluminum bath

基于步冷曲线法、CCVC法和观察法,研究了KF含量对电解质体系初晶温度、电导率、氧化铝溶解性能和阴极电解膨胀率的影响。结果表明:初晶温度随KF含量的增加而降低,平均每增加1%的KF,初晶温度降低1.83℃左右;电导率随过热度增加而增大,过热度每增加1℃,电导率平均增大0.009 S/cm;相同过热度下,KF每减小1%,电导率平均升高0.033 S/cm;相同过热度下,KF含量对氧化铝溶解速度的影响较小;阴极炭块的电解膨胀率随KF含量的增加而增大。本工作旨在研究KF含量对铝电解质物理化学性质的影响,为铝电解工业选择适宜的电解质成分提供理论依据。

Based on the step cooling curve method,CCVC method and observation method,the effects of KF content on the liquidus temperature,conductivity,alumina solubility performance and electrolysis expansion rate of cathode were studied.The results show that the liquidus temperature decreases with the increase of KF content.For every 1%increase of KF,the liquidus temperature decreases by about 1.83℃on average;The conductivity increases with the increase of superheat.The average conductivity increases by 0.009 S/cm for every 1℃increase of superheat;Under the same superheat,the conductivity increases by 0.033 S/cm for every 1%decrease of KF;Under the same superheat,KF content has little effect on the solution rate of alumina;The electrolysis expansion rate of the cathode carbon block increases with the increase of the KF content.This work is designed to study effects of KF content on the physical and chemical properties of aluminum bath,thus providing a theoretical basis for the selection of appropriate bath composition in aluminum industry.