PROCESSES FOR PRODUCING AND COMPOSITIONS COMPRISING 2,3,3,3-TETRAFLUOROPROPENE AND/OR 1,2,3,3- TETRAFLUOROPROPENE

摘要

A process is disclosed for making CF3CF═CH2 or mixtures thereof with CHF═CFCHF2. The process involves contacting CCl3CF2CF3 and optionally CCl2FCF2CClF2 with H2 in the presence of a catalyst including a catalytically effective amount of palladium supported on a support of alumina, fluorided alumina and/or aluminum fluoride, to produce a product mixture including CH2═CFCF3 (and when CCl2FCF2CClF2 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 CCl3CF2CF3 and CCl2FCF2CClF2 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 CCl3CF2CF3 and optionally CCl2FCF2CClF2 with H2 in the presence of a catalytically effective amount of a hydrogenation catalyst to form CH3CF2CF3 (and when CCl2FCF2CClF2 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.