SYNTHESIS OF HFC-134a BY ISOMERIZATION AND HYDROGENATION

Suh DJ; Park TJ; Lee BG; Park KY

Korean Journal of Chemical Engineering, Vol.13, No.1, 75-81, January, 1996

For the preparation of HFC-134a, the isomerization of CFC-114 and the gydrogenation of CFC-114a were investigated. Both reactions were catalyzed by AlCl₃ catalyst. both isomerization reactions proceeded after a certain induction period probably because the catalyst needed the activation by the halogen exchange. The catalyst deactivated gradually with the time on stream. However, the deactivation rate could be reduced by removing impurities from the reactants. Isomerization rate of CFC-114 was much slower then of CFC-113, falladium supported on carbon catalyzed the hydrogenation reaction quite selective while the selectivity declined when the supper was replaced with different supports. The catalytic activity and selectivity to desired products increased in the following order. Pd/kisslguhr<Pd/silica-alumina =~Pd/silica gel<Pd/TiO₂<Pd/Al₂O₃<Pd/C

[References]

Chang TC, Chen JJ, Yeh CT, J. Catal., 96, 51 (1985)
Firth RA, Foll GE, "Process for Producing Fluorinated Hydrocarbons," U.S. Patent, 3,755,477 (1973)
Gervasutti C, Marangoni L, Marra WJ, J. Fluor. Chem., 19, 1 (1981)
Kim DW, Ihm SK, Park KY, Lee BG, HWAHAK KONGHAK, 31(6), 831 (1993)
Pope D, Smith WL, Eastlake MJ, Moss RL, J. Catal., 22, 72 (1971)
Suh DJ, Park TJ, Ihm SK, J. Catal., 149(2), 486 (1994)
Zawalski RC, "Process for Preparing Chlorofluorocarbons via an in situ Generated Activated Aluminum Trichloride Catalyst and Products Resulting Therefrom," U.S. Patent, 4,925,993 (1990)

[Referenced By]

[1] Chang TC, Chen JJ, Yeh CT, J. Catal., 96, 51 (1985)

[2] Firth RA, Foll GE, "Process for Producing Fluorinated Hydrocarbons," U.S. Patent, 3,755,477 (1973)

[3] Gervasutti C, Marangoni L, Marra WJ, J. Fluor. Chem., 19, 1 (1981)

[4] Kim DW, Ihm SK, Park KY, Lee BG, HWAHAK KONGHAK, 31(6), 831 (1993)

[5] Pope D, Smith WL, Eastlake MJ, Moss RL, J. Catal., 22, 72 (1971)

[6] Suh DJ, Park TJ, Ihm SK, J. Catal., 149(2), 486 (1994)

[7] Zawalski RC, "Process for Preparing Chlorofluorocarbons via an in situ Generated Activated Aluminum Trichloride Catalyst and Products Resulting Therefrom," U.S. Patent, 4,925,993 (1990)