The reason for the decrease of the melting temperature after addition of sodium fluoroaluminate in alumina

We all know that in the case of electrolytic aluminum need to add sodium fluoroaluminate to reduce the melting point of alumina, which is a very important use of sodium aluminosilicate use, then add sodium aluminosilicate is not the melting point of alumina is reduced What? 
First of all, we can certainly tell you that the addition of sodium fluoroaluminate after the melting point of alumina did not decrease, it is because the addition of sodium fluoroaluminate, the sodium aluminate sodium melting point is relatively low, heating, he will first melt, change For the liquid, and alumina can be dissolved in this liquid, so see the case is the melting of alumina.

Alumina is not a salt compound, dissolved in the sodium fluoroaluminate melt is a chemical dissolution rather than physical dissolution, alumina dissolved a huge thermal effect. Alumina is the raw material for industrial aluminum electrolysis. In industrial production, we hope that alumina can dissolve more rapidly in the molten salt of sodium fluoroaluminate, maintain the concentration of alumina in the electrolytic cell, and provide stable raw materials for the continuous electrolysis Supply, so that you can reduce the anode effect and the bottom of the tank precipitation, stable production. But the actual production of alumina in the solubility of sodium fluoroaluminate is very low, by monitoring the tank resistance changes in time according to the resistance curve in the computer by automatic control of the use of overexposure and excess feeding method to control the way to the alumina concentration, As far as possible to maintain the relative stability of the alumina concentration, the more stable the concentration of alumina, the less the effect of the anode, the more energy-saving effect, the resulting effect of less gas. In recent years, due to the industrialization of low-temperature aluminum electrolysis popularization, alumina solubility in the system of sodium fluoroaluminate to further reduce the solubility of alumina and feeding control put forward higher requirements.