Preparation method of ammonium fluoride or ammonium bifluoride

Abstract

The invention belongs to the technical field of compound production, and particularly relates to a preparation method of ammonium fluoride or ammonium bifluoride. The preparation method adopts a sectional reaction; anhydrous hydrofluoric acid and liquid ammonia are divided into a plurality of batches; after the first batch of anhydrous hydrofluoric acid is added, liquid ammonia with a corresponding amount is used for neutralization; then a second batch of anhydrous hydrofluoric acid is added again, and a corresponding amount of liquid ammonia is used for neutralization; and anhydrous hydrofluoric acid and liquid ammonia are sequentially and alternately added until the reaction is completely finished. According to the preparation method of ammonium fluoride or ammonium hydrogen fluoride, the amount of anhydrous hydrofluoric acid and liquid ammonia is divided into multiple batches for reaction by adopting the sectional reaction, process conditions are easy to control, no raw material is wasted, a reaction endpoint is monitored by adopting a rapid acid-base titration method, the method is accurate, simple, convenient and rapid, the quality of the obtained product is stable, and the requirement of a first-grade product can be met.

Description

technical field

[0001] The invention belongs to the technical field of compound production, and in particular relates to a preparation method of ammonium fluoride or ammonium bifluoride. Background technique

[0002] Ammonium fluoride is a white needle-like crystal, easy to absorb moisture, soluble in cold water, slightly soluble in ethanol, decomposed into ammonia and hydrogen fluoride when heated, and decomposed into ammonia and ammonium bifluoride in hot water. Its aqueous solution is acidic and can corrode glass. Relative density 1.015, toxic, median lethal dose (rat, abdominal cavity) 32mg / kg, corrosive, can be used as chemical reagent, glass etchant (participating in hydrofluoric acid), disinfectant and preservative in fermentation industry, by oxidation Solvent for beryllium metal beryllium and surface treatment agent for silicon steel plates. It is also used in the manufacture of ceramics, magnesium alloys, cleaning and descaling of boiler feed water systems and stea...