摘要 |
In the synthesis of 1,1,1,3,3-pentafluorobutane (R-365mfc), a mixture of R-365mfc and the impurity 1,1,1,3-tetrafluoro-2-butene (R-1354mzy) is purified and R-1354mzy is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1354mzy in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture. The R-1354mzy is reduced to below 10 wt. ppm as it is converted to 2,3-dichloro-1,1,1,3-tetrafluorobutane (R-354) or other butane containing more chlorine and having a higher boiling point than R-365mfc. The butane(s) may be separated more easily from R-365mfc. The photochlorination is effected in a manner such that at least about 96 weight percent of the starting amount of R-365mfc is maintained in the mixture.
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