Regenerable solid imine sorbents

• US 8,530,375 B2
• Filed: 08/28/2009
• Issued: 09/10/2013
• Est. Priority Date: 08/18/2006
• Status: Active Grant

• Current Assignee: US Department of Energy (Government of the United States of America), University of Pittsburgh of The Commonwealth System of Higher Education
• Original Assignee: US Department of Energy (Government of the United States of America), University of Pittsburgh of The Commonwealth System of Higher Education
• Inventors: Gray, McMahan, Champagne, Kenneth J., Fauth, Daniel, Beckman, Eric
• Primary Examiner(s): JOHNSON, EDWARD M
• Application Number:
  US12/549,661
• Publication Number:
  US 20100292072A1
• Time in Patent Office: 1,474 Days
• Field of Search: 502/401, 502/402
• US Class Current: 502/401
• CPC Class Codes: B01J 20/26 Synthetic macromolecular compounds
• CPC Class Codes: B01J 20/261 obtained by reactions only involving carbon to carbon unsaturated bonds macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds per se C08F
• CPC Class Codes: B01J 20/262 obtained otherwise than by reactions only involving carbon to carbon unsaturated bonds, e.g. obtained by polycondensation macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds per se C08G
• CPC Class Codes: B01J 20/265 modified or post-treated polymers polymer carriers or substrates subjected to further impregnating or coating B01J20/3208
• CPC Class Codes: B01J 20/28057 Surface area, e.g. B.E.T specific surface area
• CPC Class Codes: B01J 20/28097 being coated, filled or plugged with specific compounds
• CPC Class Codes: B01J 20/321 consisting of a polymer obtained by reactions involving only carbon to carbon unsaturated bonds
• CPC Class Codes: B01J 20/3212 consisting of a polymer obtained by reactions otherwise than involving only carbon to carbon unsaturated bonds
• CPC Class Codes: B01J 20/3248 the functional group or the linking, spacer or anchoring group as a whole comprising at least one type of heteroatom selected from a nitrogen, oxygen or sulfur, these atoms not being part of the carrier as such
• CPC Class Codes: B01J 20/3255 comprising a cyclic structure containing at least one of the heteroatoms nitrogen, oxygen or sulfur, e.g. heterocyclic or heteroaromatic structures
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

Two new classes of amine-based sorbents are disclosed. The first class comprises new polymer-immobilized tertiary amine sorbents; the second class new polymer-bound amine sorbents. Both classes are tailored to facilitate removal of acid anhydrides, especially carbon dioxide (CO₂), from effluent gases. The amines adsorb acid anhydrides in a 1:1 molar ratio. Both classes of amine sorbents adsorb in the temperature range from about 20° C. upwards to 90° C. and can be regenerated by heating upwards to 100° C.

Claims

1. A sorbent for acid anhydrides comprising:

a) a support substrate selected from the group consisting of polyethers, polystyrenes, siloxanes, polyacrylates, and combinations thereof;

b) a tertiary amine selected from the consisting of 1,8 Diazabicyclo-[5.4.0]-undec-7-ene (DBU);

1,3,4,6,7,8-Hexahydro-2H-pyrimido[1,2,-a]pyrimidine (TBD), and N-(2-Hydroxyethyl)piperazine immobilized within the pores of the substrate; and

c) wherein a 1;

1 molar ratio of said acid anhydrides to the tertiary amine defines the maximum sorbent loading capacity.

2. The sorbent as recited in claim 1 wherein the acid anhydride is a gas selected from the group consisting of C0₂, S0₂, and NO_x.

3. The sorbent as recited in claim 1 wherein the sorbent adsorbs said acid anhydrides in the temperature range from 20°

C. to 85°

C.

4. The sorbent as recited in claim 1 wherein the molar ratio of the support substrate to amine is between 2.5:

1 and 5;

1.

5. The sorbent as recited in claim 1 wherein the surface area of the sorbents range from 50 meters squared per gram (m²/g) to 1000 m²/g.

6. The sorbent as recited in claim 1 wherein the sorbents can be formed into a solid phase selected from the group consisting of extrudates, films, powders, pellets, or monoliths to accommodate various reactor configurations.

7. The sorbent as recited in claim 1 wherein the sorbent is regenerated by heating to at or above 90°

C.

15. The sorbent of claim 1 wherein the amine is solid.

16. The sorbent of claim 1 wherein the amine has a boiling point above 100°

C.

17. The sorbent of claim 1 wherein the sorbent retains the amine after exposure to anhydride.

8. A sorbent for removing acid anhydrides from a flue gas stream comprising:

a) a support substrate selected from the group consisting of polyethers, polystyrenes, siloxanes, polyacrylates, and combinations thereof;

b) a tertiary amine selected from the consisting of acyclic imines, cyclic imines, acyclic amidines, cyclic amidines, acyclic guanidines, and cyclic guanidines immobilized within the pores; and

,

c) wherein a 1;

1 molar ratio of said acid anhydrides to the tertiary amine defines the maximum sorbent loading capacity.

9. The sorbent as recited in claim 8 wherein the acid anhydride is a gas selected from the group consisting of C0₂, S0₂, and NO_x.

10. The sorbent as recited in claim 8 wherein the sorbent adsorbs acid anhydride in the temperature range from 20°

C. to 85°

C.

11. The sorbent as recited in claim 8 wherein the sorbent can be used in the pressure range from 5 Torr to 5 atmospheres (atm).

12. The sorbent as recited in claim 8 wherein the surface area of the sorbents ranges from of about 50 meters squared per gram (m²/g) to 1000 m²/g.

13. The sorbent as recited in claim 8 wherein the sorbents can be formed into a solid phase selected from the group of extrudates, films, powders, pellets, or monoliths to accommodate various configurations.

14. The sorbent as recited in claim 8 wherein the sorbent can be regenerated by heating to or above 90°

C.