The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 2000
Filed:
Jul. 27, 1998
Stephen Frederic Yates, Cook County, IL (US);
Romulus Gaita, Cook County, IL (US);
Allied Signal Inc., Morristown, NJ (US);
Abstract
In the synthesis of 1,1,1,3,3-pentafluoropropane (R-245fa), a mixture of R-245fa and the impurity 1-chloro-3,3,3-trifluoropropene (R-1233zd) is purified and R-1233zd is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1233zd 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-1233zd being reduced to below 10 wt. ppm or lower, as it is converted to 1,2,2-trichloro-3,3,3-trifluoropropane (R-233) or other propane which contains more chlorine and which has a higher boiling point than R-245fa and can be separated easily from R-245fa, the photochlorination being effected in a manner such that at least about 96 wt. % of the starting amount of R-245fa is maintained in the mixture.