Catalytic hydrogenation of fluoroolefins, alpha-alumina supported palladium compositions and their use as hydrogenation catalysts
View Patent ↗A hydrogenation process is disclosed. The process involves reacting a fluoroolefin with H 2 in a reaction zone in the presence of a palladium catalyst to produce a hydrofluoroalkane product, wherein the palladium catalyst comprises palladium supported on a carrier wherein the palladium concentration is from about 0.001 wt % to about 0.2 wt % based on the total weight of the palladium and the carrier. Also disclosed is a palladium catalyst composition consisting essentially of palladium supported on α-Al 2 O 3 wherein the palladium concentration is from about 0.001 wt % to about 0.2 wt % based on the total weight of the palladium and the α-Al 2 O 3 . Also disclosed is a hydrogenation process comprising reacting a fluoroolefin with H 2 in a reaction zone in the presence of a palladium catalyst to produce a hydrofluoroalkane product, characterized by: the palladium catalyst consisting essentially of palladium supported on α-Al 2 O 3 wherein the palladium concentration is from about 0.001 wt % to about 0.2 wt % based on the total weight of the palladium and the α-Al 2 O 3 . Also disclosed is a hydrogenation process comprising (a) passing a mixture comprising fluoroolefin and H 2 through a bed of palladium catalyst in a reaction zone wherein the palladium catalyst comprises palladium supported on a carrier; and (b) producing a hydrofluoroalkane product; characterized by: the palladium catalyst in the front of the bed having lower palladium concentration than the palladium catalyst in the back of the bed.
1. A hydrogenation process comprising reacting a fluoroolefin with H 2 in a reaction zone in the presence of a palladium catalyst having the formula C n —H m F 2n−m and diluent to produce a hydrofluoroalkane product of formula C n H m+2 F 2n−m , wherein n is an integer from 2 to 8 and m is an integer from 0 to 2n−1, wherein said palladium catalyst comprises palladium supported on a carrier, wherein the carrier is α-Al 2 O 3 and wherein the palladium concentration is from about 0.001 wt % to about 0.1 wt % based on the total weight of the palladium and the carrier wherein the diluent is co-fed to the reaction zone with the fluorination and H 2 starting materials, wherein the molar ratio of the diluent to the fluoroolefin starting material ranges from about 10:1 to about 1:1, and wherein the diluents is said hydrofluoroalkane product.
2. The hydrogenation process of claim 1 wherein the palladium concentration of the palladium catalyst is from about 0.001 wt % to about 0.04 wt % based on the total weight of the palladium and the carrier.
3. The hydrogenation process of claim 1 wherein the palladium concentration of the palladium catalyst is from about 0.015 wt % to about 0.025 wt % based on the total weight of the palladium and the carrier.
4. The hydrogenation process of claim 1 wherein the fluoroolefin is CF 3 CF═CF 2 and the hydrofluoroalkane product is CF 3 CHFCHF 2 .
5. The hydrogenation process of claim 4 wherein the molar ratio of the CF 3 CHFCHF 2 diluent to CF 3 CF═CF 2 is from about 5:1 to about 1:1.
6. The hydrogenation process of claim 1 wherein the fluoroolefin is CF 3 CF═CHF and the hydrofluoroalkane product is CF 3 CHFCH 2 F.
7. The hydrogenation process of claim 6 wherein the molar ratio of the CF 3 CHFCH 2 F diluent to CF 3 CF═CHF is from about 5:1 to about 1:1.
8. The hydrogenation process of claim 1 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction zone is from about 0.1:1 to about 100:1.
9. A palladium catalyst composition consisting essentially of palladium supported on α-Al 2 O 3 wherein the palladium concentration is from about 0.001 wt % to about 0.1 wt % based on the total weight of the palladium and the α-Al 2 O 3 .
10. The palladium catalyst composition of claim 9 wherein the palladium concentration is from about 0.001 wt % to about 0.08 wt % based on the total weight of the palladium and the α-Al 2 O 3 .
11. The palladium catalyst composition of claim 9 wherein the palladium concentration is from about 0.001 wt % to about 0.04 wt % based on the total weight of the palladium and the α-Al 2 O 3 .
12. The palladium catalyst composition of claim 9 wherein the palladium concentration is from about 0.015 wt % to about 0.025 wt % based on the total weight of the palladium and the α-Al 2 O 3 .
13. The hydrogenation process of claim 8 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction ranges from about 0.5:1 to about 5:1.
14. The hydrogenation process of claim 13 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction ranges from about 0.9:1 to about 3:1.