Preparation method of hydrogen fluoride

Abstract

The invention discloses a preparation method of hydrogen fluoride. The preparation method comprises the following steps of: (1) carrying out acidolysis reaction on ammonium fluoride crystals and concentrated sulfuric acid which are added in a reactor, and educing coarse hydrogen fluoride gasses generated in the acidolysis reaction from a hydrogen fluoride gas outlet on the upper part of the reactor; (2) carrying out indirect heating and analysis on liquid after reaction entering into a tube still heater below a resolver through steam so as to analyze and volatize a great quantity of hydrogen fluoride dissolved in the reaction liquid, educing hydrogen fluoride from a hydrogen fluoride outlet on the top of the resolver, then mixing hydrogen fluoride with the coarse hydrogen fluoride gas on the upper part of the reactor, and carrying out concentration and crystallization on NH4HSO4 serving as resolving liquid to obtain a NH4HSO4 product; and (3) carrying out conventional purification, condensation and rectification on the mixed coarse hydrogen fluoride gas which is sent to be in a refining procedure, so as to obtain anhydrous hydrofluoric acid with the purity being 99.7%. The preparation method can be used for producing the anhydrous hydrofluoric acid product with high purity, is simple in process, low in energy consumption and safe and reliable to operate, and continuous production is easy to realize. The preparation method is suitable for comprehensive utilization of fluorine resources in phosphate fertilizer industries.

Description

technical field [0001] The present invention relates to fluorine-containing compounds, in particular to hydrogen fluoride, and in particular to a method for preparing hydrogen fluoride. Background technique [0002] As we all know, a large amount of fluorine-containing gas will be produced during the production and processing of the phosphorus chemical industry. If it is not recycled, it will cause serious environmental pollution and cause waste of fluorine resources. At present, most of the fluorine-containing gas produced when phosphate rock is used as raw material to produce wet-process phosphoric acid fertilizers is absorbed by water to obtain fluosilicic acid. The recycling of this part of fluorosilicic acid is not only beneficial to the control of fluorine pollution, but also beneficial to the protection of fluorite resources and the effective utilization of fluorine resources. [0003] In recent years, the technology of producing anhydrous hydrogen fluoride from fluo...

AI Technical Summary

Problems solved by technology

But in the above-mentioned scheme, the method for producing hydrogen fluoride by the acidolysis reaction of ammonium fluoride salt and sulfuric acid has only carried out the technical research of the laboratory, does not illustrate the industrialized way of realizing this process; Method, a large amount of hydrogen fluoride volatilized by the reaction is dissolved in the liquid phase, resulting in low purity of hydrogen fluoride gas and high water content, which causes great difficulties for subsequent rectification and separation, and the gas can only be separated by rectification with a concentration of 40%. (3) During the acidolysis reaction, a large amount of hydrogen fluoride will be dissolved in the liquid phase, resulting in a decrease in the volatilization rate of fluorine, thereby reducing the hydrogen fluoride yield of the entire process

At present, there is no patent application for the industrial production method of hydrogen fluoride

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