METHOD FOR PRODUCING HYDROGEN FLUORIDE FROM A MIXTURE OF CALCIUM DIFLUORIDE AND SILICON DIOXIDE Russian patent published in 2021 - IPC C01B7/19 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for producing hydrogen fluoride from a mixture of calcium difluoride and silicon dioxide. The method consists in conducting a sulphuric acid decomposition of the described mixture in a ratio of 1 to 1.2 moles of H₂SO₄ per 1 mol of CaF₂, processing the mixture of HF, SiF₄ and water with an ammonia-containing agent resulting in an aqueous solution of ammonium fluoride, followed by extracting ammonium bifluoride or a mixture of ammonium bifluoride, ammonium fluoride and water from the aqueous solution of ammonium fluoride, subsequently processing in the flame of a fuel constituting methane and an oxidiser constituting oxygen, condensing hydrogen fluoride and water followed by separating hydrogen fluoride.

EFFECT: hydrogen fluoride is produced using a mixture of calcium difluoride and silicon dioxide as a fluorinated raw material, wherein the concentration of silicon dioxide is not limited and fluorine in the form of hydrogen fluoride is regenerated nearly completely from calcium difluoride.

1 cl, 1 dwg, 1 ex