Method for producing fluorinated organic compounds

Abstract

Disclosed are processes for the production of fluorinated olefins, preferably adapted to commercialization of CFCF═CH(1234yf). Three steps may be used in preferred embodiments in which a feedstock such as CCl═CClCHCl (which may be purchased or synthesized from 1,2,3-trichloropropane) is fluorinated (preferably with HF in gas-phase in the presence of a catalyst) to synthesize a compound such as CFCCl═CH, preferably in a 80-96% selectivity. The CFCCl═CHis preferably converted to CFCFClCH(244-isomer) using a SbClas the catalyst which is then transformed selectively to 1234yf, preferably in a gas-phase catalytic reaction using activated carbon as the catalyst. For the first step, a mixture of CrOand FeCl/C is preferably used as the catalyst to achieve high selectivity to CFCCl═CH(96%). In the second step, SbCl/C is preferably used as the selective catalyst for transforming 1233xf to 244-isomer, CFCFClCH. The intermediates are preferably isolated and purified by distillation and used in the next step without further purification, preferably to a purity level of greater than about 95%.