Patent ID: 6077982
Filing Date: 2000-06-20
Classification: C07C

Abstract:
A process for removing 1-chloro-3,3,3-trifluoropropene (R-1233zd) or other olefinic impurities from 1,1,1,3,3-pentafluoropropane (R-245fa) by photochlorination comprising(a) contacting a mixture consisting substantially of a predetermined weight amount of R-245fa and up to about 20,000 wt. ppm R-1233zd with about 1-5 mols of chlorine for each mol of R-1233zd or other olefins in the presence of ultraviolet light having wavelengths between about 300 and 400 nm providing an exposure greater than zero and at least 0.02 watt-hour/kg of said mixture, said photochlorination being effective to reduce the concentration in the mixture of R-1233zd or other olefins to less than 100 ppm (wt.) by converting said R-1233zd to trichloro-trifluoropropane (R-233) or other propane which contains greater amounts of chlorine, as at least about 96% of said predetermined weight amount of R-245fa is maintained in the mixture; and(b) separating the R-233 or other propane formed in (a) from R-245fa.