Continuous process for the gaseous-phase preparation of trichlorotrifluoroethane, dichlorotetrafluoroethane and monochloropentafluoroethane in controlled proportions

摘要

This invention relates to a continuous gaseous-phase process for the preparation of trichlorotrifluoroethane, dichlorotetrafluoroethane and monochloropentafluoroethane, in predetermined proportions, from tetrachloroethylene, chlorine and hydrofluoric acid in the presence of a catalyst. The process is characterized by the combination of two chlorination-fluorination reactors in sequence, a parallel fluorination-dismutation reactor, and a separation unit for extracting the desired products and recycling recovered hydrofluoric acid and non-fluorinated or insufficiently fluorinated products. The process advantageously yields dichlorotetrafluoroethane containing less than 7% asymmetric isomer, and trichlorotrifluoroethane containing less than 2% asymmetric isomer.