METHOD OF SYNTHESIS OF POLYFLUOROALKANES Russian patent published in 2002 - IPC

FIELD: chemical technology. SUBSTANCE: invention relates to a method of synthesis of fluorosubstituted hydrocarbons. Method is performed by catalytic pyrolysis of perfluoro- and polyfluorocarboxylic acids and their derivatives in the presence of hydrogen fluoride and a catalyst. Catalyst consists of a carrier promoted with alkaline metal halides. Activated carbon, magnesium, calcium, barium, zinc, aluminum, nickel oxide, silicon oxides are used as a carrier. Sodium, potassium, cesium or rubidium fluorides, iodides, bromides or chlorides are used as promoters. The content of alkaline metal halides in catalyst is from 20 to 50 % by weight. Pyrolysis is carried out at temperature 100-350 C. Hydrogen fluoride is taken in (1.5-2)-fold excess as measured for the parent component. EFFECT: improved method of synthesis, increased yield of polyfluoroalkanes. 5 cl, 1 tbl, 12 ex