A kind of preparation method of ammonium bifluoride

Abstract

The invention provides a method for preparing ammonium bifluoride. The method comprises the following steps: enabling a crude fluosilicic acid liquid to react with anhydrous liquid ammonia to form a primary reaction liquid, performing solid-liquid separation on the first reaction liquid to form solid silicon dioxide and a second reaction liquid, enabling the second reaction liquid to react with barium hydroxide to form a third reaction liquid, performing solid-liquid separation on the third reaction liquid to form solid barium sulfate and a primary ammonium bifluoride liquid, enabling the primary ammonium bifluoride liquid to react with anhydrous hydrogen fluoride to form ammonium bifluoride mother liquor, putting the ammonium bifluoride mother liquor into a crystallizer, and performing cooling crystallization, thereby obtaining a high-purity finished product, namely ammonium bifluoride, wherein the crude fluosilicic acid liquid is a byproduct of an anhydrous hydrogen fluoride production line and comprises components of fluosilicic acid, a small amount of sulfuric acid and a small amount of hydrofluoric acid. As the crude fluosilicic acid liquid is adopted to replace the anhydroushydrofluoric acid, not only is the raw material cost reduced, but also comprehensive utilization of the crude fluosilicic acid liquid is achieved, silicon dioxide and barium sulfate are also producedwhen ammonium bifluoride is prepared by using the method, and the economic benefits are increased.

Description

technical field [0001] The invention relates to the application technical field of the preparation method of ammonium bifluoride, in particular to a preparation method of ammonium bifluoride. Background technique [0002] Ammonium bifluoride is a corrosive chemical substance that decomposes into toxic fluoride, nitrogen oxides and ammonia gas when exposed to moisture and water. It dissolves in water as a weak acid and can dissolve glass; it is slightly soluble in alcohol and very easily Cold water, its aqueous solution is strongly acidic, can sublimate at higher temperatures, can corrode glass, and is corrosive to skin. It can be used as a chemical reagent, glass etchant (in combination with hydrofluoric acid), disinfectant and antiseptic in fermentation industry, solvent for metal beryllium made of beryllium oxide, and surface treatment agent for silicon steel plates. It is also used in the manufacture of ceramics and magnesium alloys. Cleaning and descaling of boiler feed...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, in the process of producing ammonium bifluoride, high-purity anhydrous hydrofluoric acid is often used as raw material, and the production cost is high, resulting in low production efficiency of the enterprise

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