Hydrogenation catalyst
The present invention relates, in part, to an alpha-alumina support for a hydrogenation catalyst useful in hydrogenating fluoroolefins. In certain aspects, it relates to a method for hydrogenating a compound by contacting an olefin reactant having at least one carbon-fluorine bond, with a supported hydrogenation catalyst. The reaction results in a product that includes a hydrogenated derivative of the olefin. In certain embodiments, the supported hydrogenation catalyst includes a zero-valent metal disposed on an alpha-alumina support.
1. A method for hydrogenating a compound comprising:
contacting a reactant comprising pentafluoropropene and/or hexafluoropropene, with a supported hydrogenation catalyst under reaction conditions effective to form a reaction product comprising a hydrogenated derivative of said pentafluoropropene and/or hexafluoropropene, wherein said supported hydrogenation catalyst comprises from 0.5 to about 10 weight percent of zero-valent palladium disposed on a support comprising about 90 percent by weight to about 99.5 percent by weight of alpha-alumina.
2. The method of claim 1 wherein said support consists essentially of alpha-alumina.
3. The method of claim 1 wherein said contacting comprises feeding said pentafluoropropene and/or hexafluoropropene into a first stage of a hydrogenation reactor at a rate resulting in a conversion of the feed pentafluoropropene and/or hexafluoropropene of from about 10% to about 60%.
4. The method of claim 3 wherein said reaction product further comprises at least a portion of said pentafluoropropene and/or hexafluoropropene from said reactant that remains unreacted subsequent to said contacting; and wherein said method further comprises converting, in one or more subsequent stages of said hydrogenation reactor, about 20 to about 100 percent of said pentafluoropropene and/or hexafluoropropene in said reaction product into said hydrogenated derivative of said pentafluoropropene and/or hexafluoropropene.
5. The method of claim 4 wherein said support consists essentially of alpha-alumina.
6. The method of claim 1 wherein said hydrogenation catalyst comprises about 0.5 weight percent of said zero-valent Pd.
7. The method of claim 1 wherein said olefin is selected from the group consisting of 1,1,2,3,3,3-hexafluoropropene; 1,2,3,3,3-pentafluoropropene; and 1,1,3,3,3-pentafluoropropene.
8. The method of claim 1 wherein said hydrogenated derivative of said olefin is selected from the group consisting of 1,1,1,2,3,3-hexafluoropropane; 1,1,1,2,3-pentafluoropropane; and 1,1,1,3,3-pentafluoropropane.
9. The method of claim 1 wherein said olefin comprises 1,1,2,3,3,3-hexafluoropropene and said hydrogenated derivative of said olefin comprises 1,1,1,2,3,3-hexafluoropropane.
10. The method of claim 1 wherein said olefin comprises 1,2,3,3,3-pentafluoropropene and said hydrogenated derivative of said olefin comprises 1,1,1,2,3-pentafluoropropane.