Determination of Viscosity and Surface Tension for High LiF and KF Content Electrolytes with Innovative Testing Method in Aluminum Electrolysis

This trend is inevitable when aluminum electrolyte raw materials containing a higher content of LiF and KF are being widely used. Though these substances are often used as regulators in aluminum electrolysis due to their high corrosivity, measuring the physical parameters of the electrolyte through ordinary measurement methods is difficult. In this paper, electrolytes with different Li and K contents at different temperatures were synthesized as simulation samples, and viscosity and surface tension were measured by a new method. The results showed that in the aluminum electrolyte with a cryolite ratio of three, KF and LiF had similar impacts on viscosity when the mechanisms were completely different. As the content increased, KF reduced the viscosity of the material through the ion lattice spacing effect, and the high mobility of LiF contributed greatly to the viscosity reduction. However, the viscosity reduced significantly only when there was a higher KF concentration. The effects of the two regulators on the surface tension were different. The rising LiF content presented a greater effect on the surface tension, and the temperature was also a main factor affecting the surface tension of the electrolyte. When the two were added together in the electrolyte, a high content of KF helped reduce the surface tension. The research in this paper plays a role in promoting the exploration of phase parameters of aluminum electrolytes with high Li and K content.