Process for accelerated capture of carbon dioxide

• US 7,998,714 B2
• Filed: 09/29/2009
• Issued: 08/16/2011
• Est. Priority Date: 09/29/2008
• Status: Active Grant

• Current Assignee: CO2 Solutions Inc.
• Original Assignee: Akermin, Inc.
• Inventors: Bucholz, Tracy L., Zvosec, Richard T., Clayton, Robert A., Shirtum, Robert P., Gellett, Wayne L., Schumacher, Joshua
• Primary Examiner(s): KAM, CHIH MIN
• Application Number:
  US12/569,850
• Publication Number:
  US 20100086983A1
• Time in Patent Office: 686 Days
• Field of Search: 435/299.1, 435/174, 435/182, 435/266, 435/438, 435/168
• US Class Current: 435/168
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: B01D 53/229 Integrated processes (Diffusion and at least one other process, e.g. adsorption, absorption)
• CPC Class Codes: B01D 53/75 Multi-step processes
• CPC Class Codes: B01D 53/85 with gas-solid contact
• CPC Class Codes: B01D 53/864 Removing carbon monoxide or hydrocarbons
• CPC Class Codes: B01D 53/8671 Removing components of defined structure not provided for in B01D53/8603 - B01D53/8668
• CPC Class Codes: C12N 11/082 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C12N 11/089 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C12N 9/88 Lyases (4.)
• CPC Class Codes: C12N 9/96 Stabilising an enzyme by forming an adduct or a composition; Forming enzyme conjugates
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/59 Biological synthesis; Biological purification

Abstract

The present invention generally relates to the removal of carbon dioxide from a gas stream, particularly a flue gas, hydrogen gas from a reformer, natural gas, or gas from a cement kiln. Immobilized enzymes for use in carbon capture and other systems are also disclosed.

Claims

1. A process for removing CO₂ from a CO₂-containing gas, the process comprising

contacting an aqueous liquid with a CO₂-containing gas to promote diffusion of the CO₂ into the aqueous liquid;

and contacting the CO₂ in the aqueous liquid with immobilized carbonic anhydrase entrapped in a polymeric immobilization material to catalyze hydration of the CO₂ and form a treated liquid containing hydrogen ions and bicarbonate ions;

wherein the polymeric immobilization material comprises a micellar or inverted micellar material.

2. The process of claim 1 wherein the aqueous liquid and CO₂-containing gas are contacted in a co-current configuration.

3. The process of claim 1 wherein the process is performed in a reaction vessel which comprises a bottom portion including a gas inlet and a liquid outlet, a top portion including a liquid inlet and a gas outlet, and a middle portion containing a plurality of particles comprising an immobilized carbonic anhydrase or coated with immobilized carbonic anhydrase entrapped in a polymeric immobilization material;

the process comprising contacting an aqueous liquid which enters the liquid inlet and flows downward in the reaction vessel with a CO₂-containing gas which enters the gas inlet and flows upward in the reaction vessel to promote diffusion of the CO₂ into the aqueous liquid and catalyze hydration of the CO₂ in the aqueous liquid in the presence of the immobilized carbonic anhydrase to form a treated liquid containing hydrogen ions and bicarbonate ions and a treated gas;

evacuating the treated liquid from the liquid outlet and evacuating the treated gas from the gas outlet.

4. The process of claim 3 wherein the CO₂-containing gas enters the gas inlet in the form of microbubbles.

5. The process of claim 1 further comprising contacting the treated liquid with particles coated with immobilized carbonic anhydrase entrapped in a polymeric immobilization material, wherein the carbonic anhydrase catalyzes conversion of the hydrogen ions and the bicarbonate ions into concentrated CO₂ and water.

6. The process of claim 1 wherein the stabilized carbonic anhydrase retains at least about 15% of its initial catalytic activity for at least about 5 days when continuously catalyzing a chemical transformation at a temperature from about 30°

C. to about 100°

C.

7. The process of claim 1 wherein the aqueous liquid comprises a base.

8. The process of claim 7 wherein the base is a metal hydroxide, a quaternary ammonium hydroxide, a metal carbonate, a conjugate base of a weak acid, a quaternary ammonium carbonate, a quaternary ammonium alkoxide, a metal amide, a metal alkyl, a metal alkoxide, metal silanoate, an amine, an alkanolamine, or a combination thereof.

9. The process of claim 1 using a system for removing CO₂ from a CO₂-containing gas comprising a reaction vessel having a bottom portion containing a gas inlet and a liquid outlet, a top portion containing a liquid inlet and a gas outlet, and a middle portion containing a plurality of particles comprising an immobilized carbonic anhydrase or coated with carbonic anhydrase entrapped in a polymeric immobilization material, the carbonic anhydrase being capable of catalyzing hydration of CO₂ into hydrogen ions and bicarbonate ions, wherein the polymeric immobilization material comprises a micellar or inverted micellar material.

10. The process for removing CO₂ from a CO₂-containing gas of claim 9 further comprising a second reaction vessel, the second reaction vessel containing particles coated with carbonic anhydrase entrapped in a polymeric immobilization material wherein the carbonic anhydrase is capable of catalyzing conversion of the hydrogen ions and the bicarbonate ions into concentrated CO₂ and water.

11. The process of claim 10 wherein the second reaction vessel contains an immobilization material comprising a micellar or inverted micellar material.

13. The process of claim 1 wherein the immobilization material entraps the carbonic anhydrase, the immobilization material being permeable to a compound smaller than the carbonic anhydrase and having the structure of either Formulae 5, 6, 7, or 8:

14. The process of claim 13 wherein the immobilization material has a structure of Formula 8.

15. The process of claim 14 wherein R₃₂ and R₃₃ are independently hydrogen, alkyl, aryl, -(substituted alkylene)-acid or a salt thereof, -(substituted alkylene)-base or a salt thereof, —

(CH₂)_qO—

(CH₂—

CH₂—

O)_z—

R_t, —

CH₂—

O—

(CH₂(CH₃)—

CH₂—

O)_z—

R_t, or a combination thereof, wherein z is an integer corresponding to a weight average molecular weight of about 150 Da to about 8000 Da, R_t is hydrogen, alkyl, substituted alkyl, aryl, or substituted aryl, and q is an integer of 2, 3, or 4.

16. The process of claim 15 wherein the acid group comprises a carboxylic, a phosphonic, a phosphoric, a sulfonic, a sulfuric, a sulfamate, a salt thereof, or a combination thereof.

17. The process of claim 15 wherein the base comprises a tertiary amine, a quaternary amine, a nitrogen heterocycle, a salt thereof, or a combination thereof.

18. The process of claim 14 wherein R₃₂ and R₃₃ are independently hydrogen, alkyl, aryl, —

(CH₂)₃—

O—

((CH₂)₂—

O)_z—

CH₃, —

(CH₂)₂—

C(O)—

O—

(CH₂)₂-imidazolium, or —

(CH₂)₃—

O—

CH₂—

CH(OH)—

N(CH₃)—

(CH₂)₂—

SO₃Na and z is an integer corresponding to a weight average molecular weight of about 150 Da to about 8000 Da.

12. A process for removing CO₂ from a CO₂-containing gas, the process comprising

contacting an aqueous liquid with a CO₂-containing gas to promote diffusion of the CO₂ into the aqueous liquid;

and contacting the CO₂ in the aqueous liquid with immobilized carbonic anhydrase entrapped in a polymeric immobilization material to catalyze hydration of the CO₂ and form a treated liquid containing hydrogen ions and bicarbonate ions;

wherein the polymeric immobilization material stabilizes the carbonic anhydrase and wherein the carbonic anhydrase retains at least about 15% of its initial catalytic activity for at least about 5 days when continuously catalyzing a chemical transformation at a temperature from about 30°

C. to about 100°

C.

19. The process of claim 12 wherein the polymeric immobilization material comprises a micellar or inverted micellar material.

20. The process of claim 12 wherein the aqueous liquid comprises a base.