Catalytic hydrogenation of fluoroolefins, alhpa-alumina supported palladium compositions and their use as hydrogenation catalysts

Patent metadata

Field	Value
Publication number	US-2017129832-A1
Application number	US-201715415960-A
Country	US
Kind code	A1
Filing date	Jan 26, 2017
Priority date	May 16, 2011
Publication date	May 11, 2017
Grant date	—

Abstract

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.

First claim

1 - 24 . (canceled)

25 . 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.

26 . The hydrogenation process of claim 25 wherein the palladium concentration of the catalyst in the front of the bed is from about 0.001 wt % to about 0.2 wt % based on the total weight of the palladium and the carrier, and the palladium concentration of the catalyst in the back of the bed is from about 0.1 wt % to about 1 wt % based on the total weight of the palladium and the carrier.

27 . The process according to claim 26 wherein the palladium concentration of the catalyst in the front of the bed is from about 0.001 wt % to about 0.08 wt % based on the total weight of the palladium and the carrier, and the palladium concentration of the catalyst in the back of the bed is from about 0.2 wt % to about 0.8 wt % based on the total weight of the palladium and the carrier.

28 . The process according to claim 26 wherein the palladium concentration of the catalyst in the front of the bed is from about 0.001 wt % to about 0.04 wt % based on the total weight of the palladium and the carrier, and the palladium concentration of the catalyst in the back of the bed is from about 0.3 wt % to about 0.6 wt % based on the total weight of the palladium and the carrier.

29 . The process according to claim 26 wherein the palladium concentration of the catalyst in the front of the bed is from about 0.015 wt % to about 0.025 wt % based on the total weight of the palladium and the carrier, and the palladium concentration of the catalyst in the back of the bed is from about 0.3 wt % to about 0.6 wt % based on the total weight of the palladium and the carrier.

30 . The process according to claim 25 wherein the fluoroolefin has the formula C n -H m F 2n−m and the hydrofluoroalkane product has the 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.

31 . The process according to claim 25 wherein the fluoroolefin has the formula C n -H m F 2n−m and the hydrofluoroalkane product has the 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 and the carrier is α-Al 2 O 3 .

32 . The hydrogenation process of claim 25 wherein the fluoroolefin is CF 3 CF═CF 2 and the hydrofluoroalkane product is CF 3 CHFCHF 2 .

33 . The hydrogenation process of claim 32 wherein a CF 3 CHFCHF 2 diluent is co-fed with CF 3 CF═CF 2 and H 2 to the reaction zone and wherein the molar ratio of the CF 3 CHFCHF 2 diluent to CF 3 CF═CF 2 is from about 100:1 to about 1:1.

34 . The hydrogenation process of claim 33 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.

35 . The hydrogenation process of claim 25 wherein the fluoroolefin is CF 3 CF═CHF and the hydrofluoroalkane product is CF 3 CHFCH 2 F.

36 . The hydrogenation process of claim 35 wherein CF 3 CHFCH 2 F diluent is co-fed with CF 3 CF═CHF and H 2 to the reaction zone and wherein the molar ratio of the CF 3 CHFCH 2 F diluent to CF 3 CF═CHF is from about 100:1 to about 1:1.

37 . The hydrogenation process of claim 36 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.

38 . The hydrogenation process of claim 25 wherein the carrier is selected from the group consisting of Al 2 O 3 , fluorinated Al 2 O 3 , AlF 3 , carbon, Cr 2 O 3 , SiO 2 , TiO 2 , ZrO 2 and ZnO.

39 . The hydrogenation process of claim 38 wherein the carrier is Al 2 O 3 .

40 . The hydrogenation process of claim 39 wherein the carrier is α-Al 2 O 3 .

41 . The hydrogenation process of claim 38 wherein the carrier is carbon.

42 . The hydrogenation process of claim 25 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction zone is from about 0.1:1 to about 100:1.

43 . The hydrogenation process of claim 25 wherein said hydrogenation process is conducted in the presence of a diluent.

44 . The hydrogenation process of claim 43 wherein said diluent is co-fed with the fluoroolefin and H 2 to the reaction zone.

45 . The hydrogenation process of claim 42 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction ranges from about 0.5:1 to about 5:1.

46 . The hydrogenation process of claim 45 wherein the molar ratio of H 2 to fluoroolefin fed to the reaction ranges from about 0.9:1 to about 3:1.

Assignees

• Chemours Co Fc Llc

Inventors

• Cheung Patricia
• Lamarca Concetta

Classifications

• C07C2523/44

  Palladium · CPC title

• B01J21/04

  Alumina · CPC title

• C07C19/08

  containing fluorine · CPC title

• B01J23/44

  Palladium · CPC title

• C07C17/354 Primary

  by hydrogenation · CPC title