Carbon dioxide sorbents

• US 8,470,074 B2
• Filed: 12/20/2010
• Issued: 06/25/2013
• Est. Priority Date: 12/22/2009
• Status: Expired due to Fees

• Current Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Inventors: Baugh, Lisa S., Calabro, David C., Li, Quanchang, Berluche, Enock
• Primary Examiner(s): Zimmer, Anthony J
• Application Number:
  US12/973,562
• Publication Number:
  US 20110150730A1
• Time in Patent Office: 918 Days
• Field of Search: 423/220, 423/228, 423/230, 502/401, 502/407, 95/90, 952/36, 951/39
• US Class Current: 95/139
• CPC Class Codes: B01D 2252/20415 Tri- or polyamines
• CPC Class Codes: B01D 2252/20421 Primary amines
• CPC Class Codes: B01D 2252/20426 Secondary amines
• CPC Class Codes: B01D 2252/20431 Tertiary amines
• CPC Class Codes: B01D 2252/20436 Cyclic amines
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B01J 20/103 comprising silica
• 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 20/2803 Sorbents comprising a binder, e.g. for forming aggregated, agglomerated or granulated products
• CPC Class Codes: B01J 20/2805 Sorbents inside a permeable or porous casing, e.g. inside a container, bag or membrane
• CPC Class Codes: B01J 20/28057 Surface area, e.g. B.E.T specific surface area
• CPC Class Codes: B01J 20/28083 being in the range 2-50 nm, i.e. mesopores
• CPC Class Codes: B01J 20/28097 being coated, filled or plugged with specific compounds
• CPC Class Codes: B01J 20/3204 Inorganic carriers, supports or substrates
• CPC Class Codes: B01J 20/3272 Polymers obtained by reactions otherwise than involving only carbon to carbon unsaturated bonds
• CPC Class Codes: C08G 73/0206 Polyalkylene(poly)amines
• CPC Class Codes: C08G 73/0213 Preparatory process
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/151 : Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

Improved CO₂ sorbents comprised of a mesoporous silica functionalized with a polyamine are obtained by the in-situ polymerization of azetidine. Also included herein are processes utilizing the improved CO₂ sorbents wherein CO₂ is chemisorbed onto the polyamine portion of the sorbent and the process is thermally reversible.

Claims

1. A method for removing CO, from a CO₂-containing gaseous stream, which method comprises contacting said stream with a functionalized adsorbent material comprising a mesoporous silica material having at least a portion of its pores functionalized with in-situ polymerized cyclic amine having a density of amine sites below 20.0 mmol amine/gram.

2. The method of claim 1 wherein the in-situ polymerized cyclic amine is poly(azetidine).

3. The method of claim 2 wherein the in-situ polymerized cyclic amine has a branched structure and contains primary, secondary, and tertiary amine sites.

4. The method of claim 3 wherein the ratios of primary:

secondary;

tertiary amines in the in-situ polymerized cyclic amine ranges from between about 2;

96;

2 to about 46;

8;

46.

5. The method of claim 1 wherein the functionalized adsorbent material has a BET surface area from about 100 m²/g to about 1500 m²/g, and a pore volume from about 0.3 cc/g to about 1.8 cc/g.

6. The method of claim 2 wherein the functionalized adsorbent material further comprises one or more additional components selected from the group consisting of amorphous silica binder, aluminum oxide binder, residual polymerization solvent, and residual polymerization initiator.

7. A method for removing CO₂ from a CO₂-containing gaseous stream, which method comprises contacting said gaseous stream with a liquid phase sorbent comprising an aqueous solution of a polymerized cyclic amine having a density of amine sites below 20.0 mmol amine;

gram.

8. The method of claim 7 wherein the polymerized cyclic amine is poly(azetidine).

9. The method of claim 8 wherein the poly(azetidine) has a branched structure and contains primary, secondary, and tertiary amine sites.

10. The method of claim 9 wherein the ratios of primary:

secondary;

tertiary amines in the polymerized cyclic amine ranges from between about 2;

96;

2 to about 46;

8;

46.

11. The method of claim 10 wherein the polymerized cyclic amine comprises from about 1% to about 30% of the total weight of the liquid phase sorbent.

12. The method of claim 11 wherein the contacting is performed at a temperature from about 15°

C. to about 120°

C. to form chemisorption products.

13. The method of claim 12 wherein the liquid phase sorbent is comprised of water;

the chemisorption products comprise a mixture of carbamate, bicarbonate, and carbonate species; and

the chemisorption products maintain solubility in water.

14. A method for removing CO₂ from CO₂-containing gaseous stream, which method comprises contacting said stream with a sorbent material, wherein the sorbent material is selected from the group consisting of a functionalized adsorbent material and a liquid phase sorbent material, the functionalized adsorbent material comprising a mesoporous silica material having at least a portion of its pores functionalized with in-situ poly(azetidine) having a density of amine sites below 20.0 mmol amine/gram, and the liquid phase sorbent comprising an aqueous solution of poly(azetidine) having a density of amine sites below about 20.0 mmol amine/gram.