METHOD OF PRODUCING ANHYDROUS HYDROGEN FLUORIDE AND HYDROFLUORIC ACID Russian patent published in 2012 - IPC C01B7/19 

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of inorganic substances and can be used to produce hydrofluoric acid and anhydrous hydrogen fluoride. In the method of producing anhydrous hydrogen fluoride and hydrofluoric acid through rectification of hydrofluoric acid containing over 65 wt % hydrogen fluoride to obtain hydrogen fluoride in the distillate and hydrofluoric acid in the still residue, the process is carried out at vapour temperature in the bottom part of the column in the range of 115-130°C and reflux-to-product ratio equal to 2-5, where content of the basic substance in hydrogen fluoride is not less than 99.95% and hydrofluoric acid 40-45%.

EFFECT: method enables to obtain from aqueous solutions containing over 65 wt % HF, 40-45% hydrofluoric acid and anhydrous hydrogen fluoride with content of basic substance not less than 99,95% in one rectification separation step.

3 tbl