Membranes and Reactors for CO2 Separation

• US 20120014852A1
• Filed: 07/13/2011
• Published: 01/19/2012
• Est. Priority Date: 07/13/2010
• Status: Active Grant

• Current Assignee: University of South Carolina
• Original Assignee: University of South Carolina
• Inventors: Huang, Kevin
• Granted Patent: US 8,506,677 B2
• Time in Patent Office: Days
• US Class Current: 423/210.5
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2325/26 Electrical properties
• CPC Class Codes: B01D 53/228 characterised by specific membranes
• CPC Class Codes: B01D 67/0041 by agglomeration of particles in the dry state
• CPC Class Codes: B01D 67/00411 by sintering
• CPC Class Codes: B01D 67/0074 from melts
• CPC Class Codes: B01D 69/10 Supported membranes; Membrane supports
• CPC Class Codes: B01D 69/142 with "carriers"
• CPC Class Codes: B01D 71/024 Oxides
• CPC Class Codes: C01B 2203/0211 containing a non-catalytic reforming step
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/0405 Purification by membrane separation
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 3/34 by reaction of hydrocarbons with gasifying agents
• CPC Class Codes: C01B 3/48 followed by reaction of water vapour with carbon monoxide
• CPC Class Codes: C01B 3/503 characterised by the membrane
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

The present disclosure relates to a system for carbon dioxide separation. The system includes a conducting membrane having two phases. The first phase is a solid oxide porous substrate. The second phase is molten carbonate. The second phase is positioned within the solid oxide porous substrate of the first phase. The system also includes a H₂ and CO₂ gas input stream separated from a CH₄ gas input stream by the conducting membrane. The CO₂ is removed from the H₂ and CO₂ gas input stream as it contacts the membrane resulting in a H₂ gas output stream from the H₂ and CO₂ gas input stream and a CO and H₂ gas output stream from the CH₄ gas input stream.

Claims

1. A system for carbon dioxide separation comprising:

a conducting membrane comprising two phases, the first phase comprising a solid oxide porous substrate, the second phase comprising molten carbonate, wherein the second phase is positioned within the solid oxide porous substrate of the first phase; and

a H₂ and CO₂ gas input stream separated from a CH₄ gas input stream by the conducting membrane, wherein the CO₂ is removed from the H₂ and CO₂ gas input stream as it contacts the membrane resulting in a H₂ gas output stream from the H₂ and CO₂ gas input stream and a CO and H₂ gas output stream from the CH₄ gas input stream.

2. A system as in claim 1, wherein the CO₂ forms CO₃²⁻

when contacting the membrane.

3. A system as in claim 2, wherein the CO₃²⁻

contacts the CH₄ gas input stream to form the CO and H₂ gas output stream.

4. A system as in claim 1, wherein the solid oxide porous substrate comprises doped CeO₂.

5. A system as in claim 1, wherein the solid oxide porous substrate comprises doped ZrO₂.

6. A system as in claim 1, further comprising a water-gas shift reactor, wherein the CO and H₂ gas output stream contact the water-gas shift reactor to form a H₂ and CO₂ gas output stream.

7. A system as in claim 6, wherein the H₂ and CO₂ gas output stream combines with the H₂ and CO₂ gas input stream.

8. A system as in claim 1, wherein the second phase is held in place within the solid oxide porous substrate of the first phase by capillary force.

9. A system for carbon dioxide separation comprising:

a conducting membrane comprising two phases, the first phase comprising a solid oxide porous substrate, the second phase comprising molten carbonate, wherein the second phase is positioned within the solid oxide porous substrate of the first phase;

water-gas shift reactor; and

a H₂ and CO₂ gas input stream separated from a CH₄ gas input stream by the conducting membrane, wherein the CO₂ is removed from the gas input stream as it contacts the membrane resulting in a H₂ gas output stream from the H₂ and CO₂ gas input stream and a CO and H₂ gas output stream from the CH₄ gas input stream, and wherein the CO and H₂ gas output stream contact the water-gas-shift reactor to form a H₂ and CO₂ gas output stream.

10. A system as in claim 9, wherein the H₂ and CO₂ gas output stream combines with the H₂ and CO₂ gas input stream.

11. A method of carbon dioxide separation comprising:

contacting a H₂ and CO₂ gas input stream with a conducting membrane comprising two phases, the first phase comprising a solid oxide porous substrate, the second phase is positioned within the solid oxide porous substrate of the first phase and comprises molten carbonate; and

utilizing the conducting membrane to separate the H₂ and CO₂ gas input stream from a CH₄ gas input stream, wherein the CO₂ is removed from the H₂ and CO₂ gas input stream as it contacts the membrane resulting in a H₂ gas output stream from the H₂ and CO₂ gas input stream and a CO and H₂ gas output stream from the CH₄ gas input stream.

12. A method as in claim 11, further comprising forming CO₃²⁻

when the CO₂ contacts the membrane.

13. A method as in claim 12, further comprising contacting CO₃²⁻

with the CH₄ gas input stream to form the CO and H₂ gas output stream.

14. A method as in claim 11, wherein the solid oxide porous substrate comprises doped CeO₂.

15. A method as in claim 11, wherein the solid oxide porous substrate comprises doped ZrO₂.

16. A method as in claim 11, further comprising contacting the CO and H₂ gas output stream with a water-gas-shift reactor to form a H₂ and CO₂ gas output stream.

17. A method as in claim 16, further comprising combining the H₂ and CO₂ gas output stream with the H₂ and CO₂ gas input stream.

18. A method as in claim 11, wherein the second phase is held in place within the solid oxide porous substrate of the first phase by capillary force.