METHOD OF EXTRACTING FLUOROHYDROGEN

• Main Authors: SHILDS CHARL'Z DZHON, EHVING POL NIKOLAS, ROBERTS KRISTOFER
• Format: Patent
• Language: English; Russian
• Published: 10.02.2002
• Edition: 7
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; ORGANIC CHEMISTRY

chemical industry. SUBSTANCE: mixture is prepared from organic compound and fluorohydrogen. Organic compound includes 1,1,1,2-tetrafluoroethane, cloro-1,1,1,2-trifluoroethane, chlorotetrafluoroethane or the like. Mixture is contacted with solution of anhydrous potassium or cesium fluoride or with said solution containing aqueous fluorohydrogen. Concentration of alkali metal fluoride is 20-80 wt %. Upper organic and phase lower fluorohydrogen containing alkali metal fluoride are separated. Fluorohydrogen is extracted from lower fluorohydrogen phase by distillation in rectifying column or in flash vaporization apparatus. Residual fluorohydrogen-containing alkali metal fluoride is recycled for contacting with mixture to be separated. Fluorohydrogen is recovered from upper organic phase. Fluorine-containing organic compound is prepared by reacting initial organic material with flurohydrogen in liquid or gaseous phase in the presence of fluorination catalyst. Product stream containing fluorine-containing organic compound and unreacted fluorohydrogen is treated to separate compounds containing no fluorine and is separated as indicated above. Invention makes it possible to extract effectively fluorohydrogen from mixture containing less than 25 wt % of fluorohydrogen. EFFECT: more efficient extraction method. 17 cl, 1 dwg