Heterogeneous catalyzed synthesis of 1,1,1,2-tetrafluoroethane from 1,1,1,2-tetrachloroethane - thermodynamics and reaction pathways

Article abstract of DOI:10.1016/0022-1139(95)03320-D

1,1,1,2-Tetrachloroethane and its fluorinated derivatives, as well as trichloroethene, were fluorinated by hydrogen fluoride in the presence of a preconditioned chromia catalyst.The reaction pathways were derived under different conditions.Fluorinated haloalkanes are formed both by dehydrochlorination/hydrofluorination mechanisms as well as a chlorine/fluorine exchange mechanism.Thus, beside fluorinated alkanes considerable amounts of halo-olefins occur in the product mixture.A survey is given of the reaction pathways showing their dependence on the reaction conditions.These are discussed with respect to the calculated thermodynamic data. - Keywords: Heterogenous catalysis; Chlorofluorocarbon; Hydrofluorocarbon; Halocarbon; Fluorination; HFC-134a formation