Direct conversion of HCFC 225ca/cb mixture to HFC 245cb and HFC 1234yf
View Patent ↗Provided are methods for producing hydrofluorocarbons via the selective reduction of a halocarbon blend comprising 1,3-dichloro-1,1,2,2,3-pentafluoropropane.
1. A method of producing a C3 hydrofluorocarbon comprising the steps of:
(a) providing a halocarbon blend comprising 1,3-dichloro-1,1,2,2,3-pentafluoropropane and 3,3-dichloro-1,1,1,2,2-pentafluoropropane; and
(b) contacting said blend with a reducing agent wherein said 3,3-dichloro-1,1,1,2,2-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane are reduced in a ratio of at least 2:1 to produce at least one 3-carbon hydrofluorocarbon.
2. The method of claim 1 wherein said blend consists essentially of 1,3-dichloro-1,1,2,2,3-pentafluoropropane and 3,3-dichloro-1,1,1,2,2-pentafluoropropane.
3. The method of claim 1 wherein said hydrofluorocarbons are selected from the group consisting of pentafluoropropanes, tetrafluoropropanes, tetrafluoropropenes, and mixtures thereof.
4. The method of claim 1 wherein said at least one 3-carbon hydrofluorocarbon is selected from the group consisting of 1,1,1,2,2-pentafluoroproane, 1,1,1,2-tetrafluoropropane, 2,3,3,3-tetrafluoro-1-propene, and mixtures thereof.
5. The method of claim 1 wherein said reducing agent is hydrogen.
6. The method of claim 1 wherein said contacting is conducted in the presence of a supported catalyst consisting essentially of palladium.
7. The method of claim 6 wherein said supported catalyst is supported on a carbon substrate.
8. The method of claim 7 wherein said carbon substrate is granular carbon.
9. The method of claim 1 wherein said 3,3-dichloro-1,1,1,2,2-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane are reduced in a ratio of at least 5:1.
10. The method of claim 1 wherein said 3,3-dichloro-1,1,1,2,2-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane are reduced in a ratio of at least 10:1.