| abstract |
A process is disclosed for making CF3CF=CH2 or mixtures thereof with CHF=CFCHF2. The process involves contacting CCI3CF2CF3 and optionally CCI2FCF2CCIF2 with H2 in the presence of a catalyst including a catalytically effective amount of palladium supported on a support of alumina, fluorided aluminaand/or aluminum fluoride, to produce a product mixture including CH2=CFCF3 (and when CCI2FCF2CCIF2 is present, CHF=CFCHF2); recovering CH2=CFCF3 or a mixture thereof with CHF=CFCHF2 from the product mixture; and optionally, separating at least a portion of any CHF=CFCHF2 in the product mixture from the CH2=CFCF3 in the product mixture. The mole ratio of H2 to the total of CCI3CF2CF3 and CCI2FCF2CCIF2 fed to the reaction zone is between about 1 :1 and about 5:1. The present invention also provides another process for making CH2=CFCF3 Or mixtures thereof with CHF=CFCHF2 This process involves (a) reacting CCI3CF2CF3 and optionally CCI2FCF2CCIF2 with H2 in the presence of a catalytically effective amount of a hydrogenation catalyst to form CH3CF2CF3 (and when CCI2FCF2CCIF2 is present, CH2FCF2CHF2); (b) dehydrofluorinating CH3CF2CF3 and optionally any CH2FCF2CHF2 from (a) to form a product mixture including CH2=CFCF3, and if CH2FCF2CHF2 is present, CHF=CFCHF2; (c) recovering CH2=CFCF3 or a mixture thereof with CHF=CFCHF2 from the product mixture formed in (b); and optionally (d) separating at least a portion of any CHF=CFCHF2 in the product mixture formed in (b) from the CH2=CFCF3 in the product mixture formed in (b). The present invention also provides compositions involving CH2=CFCF3 and/or CHF=CFCHF2, including compositions useful as refrigerants, foam blowing agents, cleaning agents and aerosols and azeotropic compositions involving (a) CF2HCF=CFH and (b) HF. |