Using cryolite as solvent, alumina is dissolved and then electrolyzed. Cryolite plays a key role here. It solves the difficulties that alumina has a high melting point (up to 2050 ℃), is not conductive, and the melting point of cryolite cannot be electrolyzed alone. After alumina is dissolved in cryolite, it can be electrolyzed at a temperature of (940 ℃ ~ 980 ℃). Cryolite has other wonderful functions. It is lighter than aluminum in the molten state. The aluminum obtained by electrolysis sinks at the bottom of the tank and cryolite floats on it, which plays an effect of avoiding aluminum oxidation by air.

The annual sales volume of cryolite in China is about 130000 tons, which is about 700000 tons of cryolite in the world's industrial stores in 1999. The melting point of cryolite is used as a flux for electrolytic aluminum smelting. Cryolite must meet certain requirements in terms of sodium aluminum molecular ratio, impurity content and water content.

First of all, the higher the ratio of sodium to aluminum in cryolite, the better, the higher the molecular ratio, the higher the current efficiency of electrolytic aluminum smelting, the less fluorine loss, the less environmental pollution, and the polymer is more suitable for other occupations except aluminum industry than cryolite

In addition to dissolving alumina, it also has some other properties that cannot be lacked, such as no elements that correct the electrical properties than aluminum, good stability, decomposition under general conditions, the melting point of cryolite is non-volatile and non deliquescent, the melting point is higher than aluminum, good conductivity, potassium cryolite saves electricity, etc. It can be said that without cryolite, there might not be such a large-scale aluminum industry in the world, the price would not be so low, and the application would not be so extensive.

Cryolite can be divided into high molecular weight cryolite and low molecular weight cryolite according to the molecular comparison of sodium and aluminum. According to its physics course, it is divided into sandy cryolite, melting point of cryolite, granular cryolite and powdered cryolite. Different shapes, effects and requirements are also different. We can choose suitable products according to our own needs.