PROCESS FOR PREPARING 1,1,1,2-TETRAFLUOROETHANE Russian patent published in 1995 - IPC

FIELD: as a cooling agent. SUBSTANCE: synthesis conditions: hydrogen fluoride is reacted with trichloroethylene in the presence of a catalyst to form a mixture comprising 2-chloro-1,1,1-trifluoroethane and 1,1,1,2- tetrafluoroethane and optionally other organic by- products. The reaction is carried out in one reaction zone and 1,2,1,2-tetrafluoroethane is recovered from the mixture and 2,2-chloro-1,1,1-trifluoroethane and optionally other organic by-products together with trichloroethylene and HF are recycled for the mixture to the reaction. HF is used in a molar ratio of 3 to 30 times exceeding the molar ratio of trichloroethylene. The catalyst is a metal salt selected from the salts of chromium, the salts of cobalt supported on aluminium fluoride, fluorinated aluminium oxide or carbon. EFFECT: improved preparation process. 2 cl, 2 tbl