Integration of molten carbonate fuel cells in fischer-tropsch synthesis

Patent metadata

Field	Value
Publication number	US-9397355-B2
Application number	US-201514722376-A
Country	US
Kind code	B2
Filing date	May 27, 2015
Priority date	Mar 15, 2013
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

In various aspects, systems and methods are provided for integration of molten carbonate fuel cells with a Fischer-Tropsch synthesis process. The molten carbonate fuel cells can be integrated with a Fischer-Tropsch synthesis process in various manners, including providing synthesis gas for use in producing hydrocarbonaceous carbons. Additionally, integration of molten carbonate fuel cells with a Fischer-Tropsch synthesis process can facilitate further processing of vent streams or secondary product streams generated during the synthesis process.

First claim

What is claimed is:

1. A method for synthesizing hydrocarbonaceous compounds, the method comprising:
introducing a fuel stream comprising a reformable fuel into an anode of a molten carbonate fuel cell, an internal reforming element associated with the anode, or a combination thereof;
introducing a cathode inlet stream comprising CO 2 and O 2 into a cathode inlet of the molten carbonate fuel cell;
generating electricity within the molten carbonate fuel cell;
generating an anode exhaust comprising H 2 , CO, H 2 O, and CO 2 , wherein a ratio of H 2 to CO in the anode exhaust is at least about 2.1:1; and
reacting at least a portion of the anode exhaust under effective Fischer-Tropsch conditions in the presence of a shifting Fischer-Tropsch catalyst to produce at least one gaseous product and at least one non-gaseous product.

2. The method of claim 1 , wherein the ratio of H 2 to CO in the anode exhaust is at least about 2.5:1.

3. The method of claim 1 , further comprising compressing the anode exhaust, the at least a portion of the anode exhaust, or a combination thereof prior to the reacting of the at least a portion of the anode exhaust under effective Fischer-Tropsch conditions.

4. The method of claim 1 , further comprising recycling at least a portion of the one gaseous product to the cathode inlet.

5. The method of claim 1 , wherein the shifting Fischer-Tropsch catalyst comprises Fe.

6. The method of claim 1 , further comprising exposing at least a portion of the anode exhaust stream to a water gas shift catalyst to form a shifted anode exhaust, and then removing water and CO 2 from at least a portion of the shifted anode exhaust.

7. The method of claim 1 , wherein the cathode inlet stream comprises exhaust from a combustion turbine.

8. The method of claim 1 , wherein the ratio of H 2 :CO in the anode exhaust is at least about 3.0:1.

9. The method of claim 1 , wherein an amount of the reformable fuel introduced into the anode, the internal reforming element associated with the anode, or the combination thereof, is at least about 75% greater than an amount of hydrogen reacted in the molten carbonate fuel cell to generate electricity.

10. The method of claim 1 , wherein a ratio of net moles of syngas in the anode exhaust to moles of CO 2 in a cathode exhaust is at least about 2.0:1.

11. The method of claim 1 , further comprising recycling at least a portion of the gaseous product to the anode inlet, the cathode inlet, or a combination thereof.

12. A method for synthesizing hydrocarbonaceous compounds, the method comprising:
introducing a fuel stream comprising a reformable fuel into the anode of a molten carbonate fuel cell, an internal reforming element associated with a anode, or a combination thereof;
introducing a cathode inlet stream comprising CO 2 and O 2 into a cathode inlet of the molten carbonate fuel cell;
generating electricity within the molten carbonate fuel cell;
generating an anode exhaust comprising H 2 , CO, H 2 O, and CO 2 ; and
reacting at least a portion of the anode exhaust under effective Fischer-Tropsch conditions in the presence of a shifting Fischer-Tropsch catalyst to produce at least one gaseous product and at least one non-gaseous product,
wherein an amount of the reformable fuel introduced into the anode, the internal reforming element associated with the anode, or the combination thereof, provides a reformable fuel surplus ratio of at least about 1.5.

13. The method of claim 12 , wherein the ratio of H 2 to CO in the anode exhaust is at least about 2.5:1.

14. The method of claim 12 , further comprising compressing the anode exhaust, the at least a portion of the anode exhaust, or a combination thereof prior to the reacting of the at least a portion of the anode exhaust under effective Fischer-Tropsch conditions.

15. The method of claim 12 , wherein the shifting Fischer-Tropsch catalyst comprises Fe.

16. The method of claim 12 , further comprising exposing at least a portion of the anode exhaust stream to a water gas shift catalyst to form a shifted anode exhaust, and then removing water and CO 2 from at least a portion of the shifted anode exhaust.

17. The method of claim 12 , wherein the cathode inlet stream comprises exhaust from a combustion turbine.

18. The method of claim 12 , wherein an amount of the reformable fuel introduced into the anode, the internal reforming element associated with the anode, or the combination thereof, is at least about 75% greater than an amount of hydrogen reacted in the molten carbonate fuel cell to generate electricity.

19. The method of claim 12 , wherein a ratio of net moles of syngas in the anode exhaust to moles of CO 2 in a cathode exhaust is at least about 2.0:1.

20. The method of claim 12 , further comprising recycling at least a portion of the gaseous product to the anode inlet, the cathode inlet, or a combination thereof.

21. A method for synthesizing hydrocarbonaceous compounds, the method comprising:
introducing a fuel stream comprising a reformable fuel into the anode of a molten carbonate fuel cell, an internal reforming element associated with a anode, or a combination thereof;
introducing a cathode inlet stream comprising CO 2 and O 2 into a cathode inlet of the molten carbonate fuel cell;
generating electricity within the molten carbonate fuel cell;
generating an anode exhaust comprising H 2 , CO, H 2 O, and CO 2 ;
reacting at least a portion of the anode exhaust under effective Fischer-Tropsch conditions in the presence of a shifting Fischer-Tropsch catalyst to produce at least one gaseous product and at least one non-gaseous product; and
recycling at least a portion of the gaseous product to the cathode inlet, the anode inlet, or a combination thereof.

22. The method of claim 21 , wherein an amount of the reformable fuel introduced into the anode, the internal reforming element associated with the anode, or the combination thereof, provides a reformable fuel surplus ratio of at least about 1.5.

23. The method of claim 21 , wherein the ratio of H 2 to CO in the anode exhaust is at least about 2.5:1.

24. The method of claim 21 , further comprising compressing the anode exhaust, the at least a portion of the anode exhaust, or a combination thereof prior to the reacting of the at least a portion of the anode exhaust under effective Fischer-Tropsch conditions.

25. The method of claim 21 , wherein the shifting Fischer-Tropsch catalyst comprises Fe.

26. The method of claim 21 , further comprising exposing at least a portion of the anode exhaust stream to a water gas shift catalyst to form a shifted anode exhaust, and then removing water and CO 2 from at least a portion of the shifted anode exhaust.

27. The method of claim 21 , wherein the cathode inlet stream comprises exhaust from a combustion turbine.

28. The method of claim 21 , wherein an amount of the reformable fuel introduced into the anode, the internal reforming element associated with the anode, or the combination thereof, is at least about 75% greater than an amount of hydrogen reacted in the molten carbonate fuel cell to generate electricity.

29. The method of claim 21 , wherein a ratio of net moles of syngas in the anode exhaust to moles of CO 2 in a cathode exhaust is at least about 2.0:1.

Assignees

• Exxonmobil Res & Eng Co

Inventors

• Berlowitz Paul J
• Barckholtz Timothy A
• Hershkowitz Frank

Classifications

• H01M8/04761

  of fuel cell exhausts · CPC title

• C01B3/48

  followed by reaction of water vapour with carbon monoxide · CPC title

• C01B2203/0495

  the impurity being water · CPC title

• C01B2203/046

  Purification by cryogenic separation · CPC title

• C01B2203/0227

  containing a catalytic reforming step · CPC title