ALUMINUM FLUORIDE-BASED CATALYST FOR THE GAS-PHASE FLUORINATION OF HYDROCARBONS

1357415 Fluorination; chlorofluorination and disproportionation MONTECATINI EDISON SpA 9 June 1971 [10 June 1970] 17890/71 Heading C2C [Also in Division B1] Gas phase fluorination, chlorofluorination and disproportionation of hydrocarbons and halohydrocarbons, namely (i) fluorination of a halogenated ethane containing at least one chlorine atom with hydrogen fluoride to provide a fluorinated or chlorofluorinated ethane, (ii) chlorofluorination of a hydrocarbon or halohydrocarbon containing two carbon atoms to provide a chlorofluorinated ethane, and (iii) disproportionation of trifluorotrichloroethane (CF 2 ClCFCl 2 ) are effected at a temperature of from 200 to 500‹ C. in the presence of catalyst which comprises aluminium fluoride and compounds of zinc, chromium, nickel and, optionally, iron in amounts such that the catalyst contains from 0À05 to 5 weight per cent of each of zinc, chromium and nickel and from 0 to 3 weight per cent of iron. The zinc, chromium, nickel and, if present, iron may be at least partly in the form of at least one oxide and/or at least one oxyhalide and/or at least one halide, for example fluoride. The catalyst may be prepared by a process wherein alumina or aluminium fluoride is composited with compounds of zinc, chromium, nickel and, if desired, iron in divided form and the resulting composition is heated initially in a flow of nitrogen or air and thereafter in a flow of hydrogen fluoride diluted with an inert gas, the heating in the presence of hydrogen fluoride being optional if aluminium fluoride is used; the compounds of zinc, chromium, nickel and iron used in such preparation may be halides and/or compounds, for example nitrates, convertible to oxide and/or oxyhalide and/or halide by the heat regime to which the composition is subjected. Examples relate to the fluorination (Example 2) and disproportionation (Example 5) of trifluorotrichloroethane (CF 2 ClCFCl 2 ) and to the chlorofluorination of ethylene (Examples 3, 4 and 6) in the presence of various catalysts in accordance with the invention and not in accordance with the invention; each example includes full details relating to the composition of the reaction product which contains, as appropriate, compounds selected from HCl, C 2 H 2 Cl 2 , C 2 HCl 3 , C 2 FCl 3 , C 2 Cl 4 , C 2 F 5 Cl, C 2 F 4 Cl 2 (both isomers), C 2 F 3 Cl 3 (both isomers), C 2 F 2 Cl 4 (both isomers), C 2 FCl 5 and C 2 Cl 6 .