Methods for producing propylene by the dehydrogenation of propane

Patent metadata

Field	Value
Publication number	US-10662129-B2
Application number	US-201716063026-A
Country	US
Kind code	B2
Filing date	Jan 12, 2017
Priority date	Jan 21, 2016
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

Methods for producing propylene by the dehydrogenation of propane are provided. Methods can include introducing a first gas mixture including propane to a dehydrogenation catalyst at a temperature of at least about 570° C., introducing a second gas mixture including steam and air to the dehydrogenation catalyst at a temperature of at least about 550° C., and allowing the second gas mixture to subsist therewith for at least about one hour. Methods can further include introducing a third gas mixture including hydrogen to the dehydrogenation catalyst at a temperature of at least about 500° C.

First claim

The invention claimed is:

1. A method for producing propylene and regenerating a dehydrogenation catalyst, the method comprising the steps of:
(a) reacting a first gas mixture comprising propane in the presence of the dehydrogenation catalyst in a first reactor at a temperature of at least about 550° C. to about 630° C. to generate a product gas mixture comprising propylene;
(b) introducing a second gas mixture comprising steam and air to the dehydrogenation catalyst at a temperature of at least about 550° C., and allowing the second gas mixture to subsist therewith for at least about one hour and up to four hours (1-4 hours); and
(c) introducing a third gas mixture comprising hydrogen to the dehydrogenation catalyst at a temperature of at least about 500° C.;
wherein the first reactor is selected from the group consisting of a fluidized bed reactor, a moving bed reactor and a panel reactor.

2. The method of claim 1 , wherein the first gas mixture further comprises steam.

3. The method of claim 2 , wherein the first gas mixture comprises steam and propane in a molar ratio from about 2 mol/mol to about 4 mol/mol.

4. The method of claim 2 , further wherein the reaction temperature is 630° C.

5. The method of claim 2 , wherein 50 mol-% of the propane in the first gas mixture is converted.

6. The method of claim 2 , wherein 45 mol-% of the propane in the first gas mixture is converted.

7. The method of claim 2 , wherein the dehydrogenation catalyst comprises platinum.

8. The method of claim 1 , wherein the dehydrogenation catalyst comprises platinum.

9. The method of claim 8 , wherein the platinum is supported on alumina.

10. The method of claim 1 , wherein the second gas mixture is allowed to subsist with the dehydrogenation catalyst for one hour.

11. The method of claim 1 , wherein the air comprises oxygen and the second gas mixture comprises from about 2 mol-% to about 10 mol-% oxygen.

12. The method of claim 1 , wherein the second gas mixture comprises steam and air in a molar ratio from about 1 mol/mol to about 12 mol/mol.

13. The method of claim 1 , wherein from about 35 mol-% to about 50 mol-% of the propane in the first gas mixture is converted.

14. The method of claim 1 , wherein about 45 mol-% of the propane in the first gas mixture is converted.

15. The method of claim 1 , wherein the reacting temperature is about 630° C.

16. The method of claim 1 , wherein the reacting has a propylene selectivity of greater than about 86%.

17. The method of claim 1 , wherein the first reactor is a panel reactor.

18. A method for producing propylene, the method consisting of the steps of:
introducing a first gas mixture comprising propane to a dehydrogenation catalyst at a temperature of at least about 570° C. to generate a product gas mixture comprising propylene;
introducing a second gas mixture comprising steam and air to the dehydrogenation catalyst at a temperature of at least about 550° C., and allowing the second gas mixture to subsist therewith for at least about one hour to regenerate the catalyst; and
introducing a third gas mixture comprising hydrogen to the dehydrogenation catalyst at a temperature of at least about 500° C. to reduce the regenerated catalyst.

19. A method for producing propylene, the method consisting of the steps of:
(a) introducing a first gas mixture comprising propane to a dehydrogenation catalyst in a first reactor at a temperature of at least about 550° C. and up to 630° C. to generate a product gas mixture comprising propylene;
(b) introducing a second gas mixture comprising steam and air to the dehydrogenation catalyst at a temperature of at least 550° C., and allowing the second gas mixture to subsist therewith for at least about one hour; and then
(c) introducing a third gas mixture comprising hydrogen to the dehydrogenation catalyst at a temperature of at least 500° C.;
wherein the first reactor is a panel reactor;
wherein the first gas mixture further comprises steam;
wherein 50 mol-% of the propane in the first gas mixture is converted;
wherein the propylene selectivity is greater than about 86%;
wherein the air comprises oxygen and the second gas mixture comprises 2 mol-% oxygen; and
wherein the second gas mixture comprises steam and air in a molar ratio of 12 mol/mol.

Assignees

• Sabic Global Technologies Bv

Inventors

• Govindarajan Deepa
• Chithravel Venkatesan
• Venugopal B V

Classifications

• B01J38/06

  using steam · CPC title

• C07C2523/42

  Platinum · CPC title

• C07C5/48 Primary

  with oxygen as an acceptor · CPC title

• B01J23/42

  Platinum · CPC title

• C07C11/06

  Propene · CPC title