Method for preparing kryocide

Abstract

The invention relates to a method for preparing cryolite, which takes carbon residue of aluminum factories and ammonium fluoroaluminate as raw materials which are then reacted with each other in a solid phase. The method adopts a great deal of waste residue of the electrolytic aluminum factories - the carbon residue and waste residue of the aluminum section industry - the ammonium fluoroaluminate as the raw materials, thereby the method creates a source of raw materials for producing villiaumite, relieves the dependency on fluorite, saves a large number of valuable resources, has low cost, greatly reduces the production cost, and relieves the ambient environmental pollution problem. Carbon powder containing about 10 percent of electrolyte obtained after flotation of the carbon residue can be dried and then used as auxiliary materials for adequate addition when bottom paste is manufactured, and used for building a novel groove. The compositions of electrolyte in a great deal of waste residue produced by the electrolytic aluminum factories - the carbon residue are the cryolite and alumina; the method converts the alumina in the electrolyte into aluminum fluoride; and the cryolite is double salt of sodium fluoride and the aluminum fluoride. Moreover, products during the reaction process of the method can be recycled, thereby the method greatly reduces the production cost to a certain degree, has good social benefit and economic benefit, and is easy to promote and apply.

Description

technical field [0001] The invention relates to a method for preparing cryolite, in particular to a method for preparing cryolite by using carbon slag from the electrolytic aluminum industry and ammonium fluoroaluminate as raw materials. Background technique [0002] Cryolite is an alkali metal fluoroaluminate, also known as sodium fluoroaluminate, its molecular formula is Na 3 AlF 6 , which is 3NaF·AlF 3 , Natural cryolite is a monoclinic prismatic crystal, colorless, due to the influence of impurities, it is often off-white, light yellow or light red, sometimes black, and often appears as an inseparable dense block with glass luster. Slightly soluble in water, showing an acidic reaction, it will decompose when it encounters sulfuric acid. As a chemical product, cryolite is mainly used as a flux for smelting metal aluminum, and can also be used as an insecticide for crops, an enamel opalescent agent, a sunscreen and flux for glass and enamel production, and a wear-resist...

AI Technical Summary

Problems solved by technology

[0003] The traditional production process of cryolite is fluoroaluminic acid soda ash method, as well as clay brine method, sodium fluorosilicate method, hydrofluoric acid, sodium aluminate method, etc. These methods all need to occupy a certain amount of fluorine resources, and the production cost is relatively high. Moreover, the current processes all have different degrees of environmental pollution problems.

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