Effect of potassium cryolite molten salt on inert anode

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• Effect of potassium cryolite molten salt on inert anode

The corrosion of potassium cryolite molten salt on inert anode and side lining material is also serious, and it is necessary to further search for appropriate inert anode and side lining material. One of the problems of potassium cryolite electrolyte is low conductivity, resulting in large ohmic drop, although it can be compensated by adding additives such as LiF and reducing the pole distance. However, the additive also decreases the solubility of alumina and increases the initial crystal temperature while increasing the conductivity. Meanwhile, the decrease of the electrode distance also depends on the industrial application of the wettable cathode.

In addition, K+ is enriched in the cathode in the low-temperature electrolytic process, and the ratio of electrolyte molecules near the cathode increases, resulting in cathode crusting. In the electrolytic process using potassium cryolite as electrolyte, the common phenomenon is that the cell voltage is high and fluctuates greatly, and the current efficiency is low.

Although the research on potassium cryolite electrolyte has received a certain degree of attention, it is far from enough compared with the research on sodium cryolite. The physical and chemical properties of potassium cryolite are only preliminary studies and not systematic yet. The existing data are few and incomplete, and the data reported in the literature are inconsistent. Existing research is mainly focused on the conductivity and solubility of alumina and the physicochemical properties, such as crystal temperature and the physicochemical properties such as density, surface tension and viscosity research is very little, so you need to further the chemical and physical properties of potassium cryolite system research, moreover elpasolite thermodynamic data of electrolyte is relatively lack, not in-depth understanding on the structure of the molten salt, All these aspects need further study.

In addition to finding suitable inert anode materials, more research and optimization of electrolytic process are needed for the industrial application of potassium cryolite electrolyte. In addition, the study of corrosion and penetration of potassium salt to carbon cathode and wettable inert cathode is also one of the important conditions for its industrial application.