In industry, potassium fluoroaluminate is generally called potassium cryolite, which is often expressed as kalf4. Potassium cryolite can react with water to release hydrogen fluoride at high temperature, and can also slowly dissolve in strong acid to release hydrogen fluoride. Potassium cryolite has been widely used in various sectors of the economy. Its main uses are: brazing agent for aluminum, aluminum alloy and stainless steel; Composite solvent components for aluminum alloy smelting purification treatment; Raw materials for ceramic and glass industry; Additives in grinding wheel and friction agent (popular materials); Steel melting materials, etc.

Potassium cryolite is specially prepared by chemical technology, but also a by-product of some products. The preparation processes of the former include mixed grinding method and synthesis method, which can be called conventional process. The latter kind of products are the by-products of the production of Al-Ti-B Master Alloy. Al-Ti-B Master Alloy is the grain refiner of aluminum alloy, which must be added in the production of aluminum to refine the grain and structure of the alloy and improve the properties of the material. Here are some details:

1、 Conventional preparation process of potassium cryolite.

(1) Mixed grinding method, which is prepared by mixing and grinding KF, AlF3 and kalf4 according to the specified composition proportion and different methods. Some processes also use these raw materials and basic components to distribute a small amount of other fluoride to further improve the performance of brazing welding machine.

(2) Synthesis method: the main disadvantages of preparing potassium cryolite by mixed grinding method are: the basic raw materials are KF or kalf4 or K3ALF6, which is expensive and not suitable for preparation; The prepared products often contain free KF, which is easy to dissolve in water and absorb water, causing weldment corrosion. Although the melt grinding method does not have these shortcomings, it has cumbersome operation, high energy consumption and needs high-temperature melting and grinding. Therefore, a mixing method has been developed, which takes Al (OH) 3, HK, KCl, Koh, K2CO3 and KBr as raw materials to form some commercial preparation processes such as potassium metaaluminate method, potassium fluoride method, potassium aluminum hydroxide method, potassium carbonate method and potassium compound method.

2、 The by-product of producing Al-Ti-B Master Alloy.

In the production of al-5ti-ib master alloy grain refiner, 0.280tk2tif6 and 0.140tkbf4 are required without 1t aluminum. For each 1tal-5b-1ti master alloy, 0.40t potassium cryolite (kalf4) by-product can be produced at the same time. Of course, it may not be completely pure potassium cryolite, that is, it may be mixed with a small amount of K3ALF6. The physical and chemical properties of this potassium cryolite compound the requirements and indicators of QB / dfd4294-2003. Its application scope is the same as that of the produced products. As it is a by-product, it may have more price advantages in market competition.