Method of production of anhydrous hydrogen fluoride

摘要

Anhydrous hydrogen fluoride is produced from fluorosilicic acid by its decomposition with sulphuric acid in an improved process. Fluorosilicic acid of high concentration 40-50%, free of suspended silica is decomposed while being heated up to its boiling temperature with partial conversion into gaseous state. Earlier in the process evolved gaseous fluorine compounds which are desiccated by means of sulphuric acid and then separated by hydrogen fluoride absorption in a circulating liquid consisting of sulphuric acid and fluorosulphonic acid. Later hydrogen fluoride is distilled from this liquid and liquefied.