Synthetic Cryolite Can Be Used As Flux for Aluminum Electrolysis - Jinzhou Sata Fused Fluxes and New Materials Factory.
Jinzhou Sata Fused Fluxes and New Materials Factory.
Synthetic Cryolite Can Be Used As Flux for Aluminum Electrolysis


Potassium fluoroaluminate, also known as potassium synthetic cryolite and potassium ice, mainly exists in the form of potassium hexafluoroaluminate and potassium tetrafluoroaluminate. Potassium fluoroaluminate is mainly used to make brazing flux, most of the brazing fluxes are used for welding aluminum and aluminum alloy devices, and can also be used for welding other metals and alloys such as copper and iron. Potassium fluoroaluminate can also be used as a filler for abrasives and for the production of ceramics, glass (fluxing agent), and as a fluxing agent for adding various alloying elements during aluminum processing. In addition, potassium hexafluoroaluminate is processed (changing its molecular size) into potassium tetrafluoroaluminate, which can be used as an aluminum electrolysis additive.

Ⅰ. Requirements for synthetic cryolite as aluminum electrolysis flux

1. The ratio of sodium to aluminum in synthetic cryolite should be as high as possible. The higher the molecular ratio, the higher the current efficiency of electrolytic aluminum smelting. The lower the loss of fluorine, the less environmental pollution it causes. Moreover, polymers are more suitable for applications in industries other than the aluminum industry than synthetic cryolite.

2. The content of impurities such as silicon oxide, iron oxide, and phosphorus pentoxide in synthetic cryolite should be low. The presence of these impurities directly affects the quality of aluminum ingots and the current efficiency of aluminum smelting.

3. The water content of synthetic cryolite should be as low as possible. The presence of water will increase the consumption of synthetic cryolite.

Ⅱ. The role of synthetic cryolite in electrolytic aluminum production

1. After the synthetic cryolite is melted, it forms a liquid electrolyte, which has good electrical conductivity, thereby forming a power circuit in the electrolytic cell to ensure the normal progress of the electrochemical reaction.

2. The liquid electrolyte formed after the synthetic cryolite is melted is not only the electrochemical reaction zone in the electrolytic cell but also the heat capacity storage zone. The electrochemical reactions in the production of aluminum electrolysis are all carried out in the liquid electrolyte.

3. The production of aluminum electrolysis uses the liquid electrolyte formed after synthetic cryolite melting as the solute, the alumina powder is used as the flux, and the direct current is applied to carry out the electrochemical reaction. Therefore, the liquid electrolyte also has an important role in dissolving the alumina powder.

Ⅲ. The amount of synthetic cryolite

1. 15kg synthetic cryolite is consumed for every ton of aluminum produced.

2. Other mechanical losses per ton of aluminum during production operations are 5kg.

Ⅳ. The characteristics of synthetic cryolite

1. When the new starting tank is used, the electrolyte level can be stabilized, the contraction is slower, which is conducive to the stable maintenance of the electrolyte, the cathode absorbs sodium uniformly, which is beneficial to prolong the life of the electrolysis cell, the electrolysis temperature is reasonable, the change is small, it is easy to control, and the volatilization loss is small. It can effectively improve on-site working conditions.

2. A large amount of sodium fluoride or soda ash can be saved and the production cost of electrolytic aluminum can be reduced.