Regenerable supported amine-polyol sorbent

• US 5,492,683 A
• Filed: 09/16/1994
• Issued: 02/20/1996
• Est. Priority Date: 12/11/1992
• Status: Expired due to Fees

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Birbara, Philip J., Nalette, Timothy A.
• Primary Examiner(s): MCFARLANE, ANTHONY R
• Application Number:
  US08/307,968
• Time in Patent Office: 522 Days
• Field of Search: 423/228, 423/229, 423/230
• US Class Current: 423/230
• CPC Class Codes: B01D 53/02 by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/165 Natural alumino-silicates, e.g. zeolites
• CPC Class Codes: B01J 20/18 Synthetic zeolitic molecular sieves
• CPC Class Codes: B01J 20/20 comprising free carbon; comprising carbon obtained by carbonising processes
• CPC Class Codes: B01J 20/28057 Surface area, e.g. B.E.T specific surface area
• CPC Class Codes: B01J 20/28078 Pore diameter
• CPC Class Codes: B01J 20/3204 Inorganic carriers, supports or substrates
• CPC Class Codes: B01J 20/321 consisting of a polymer obtained by reactions involving only carbon to carbon unsaturated bonds
• CPC Class Codes: B01J 20/3248 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 20/3251 comprising at least two different types of heteroatoms selected from nitrogen, oxygen or sulphur
• 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: B01J 20/3272 Polymers obtained by reactions otherwise than involving only carbon to carbon unsaturated bonds
• CPC Class Codes: B01J 20/3425 of sorbents or filter aids comprising organic materials
• CPC Class Codes: B01J 20/3483 by thermal treatment not covered by groups B01J20/3441 - B01J20/3475, e.g. by heating or cooling
• CPC Class Codes: B01J 20/3491 by pressure treatment
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

The supported amine-polyol sorbent of the present invention comprises about 1 wt. % to about 25 wt. % amine, about 1 wt. % to about 25 wt. % polyol, with the balance being support. This sorbent is capable of absorbing and desorbing carbon dioxide at relatively high rates at ambient temperatures, thereby improving carbon dioxide sorption capacity.

Claims

1. A regenerable carbon dioxide removal process comprising the steps of:

a. passing a gaseous stream containing carbon dioxide through a sorbent bed, wherein said sorbent is formed from a supported amine-polyol sorbent having about 1 wt. % to about 25 wt. % polyol and about 1 wt. % to about 25 wt. % amine, with the balance being support;

b. absorbing the carbon dioxide into said sorbent; and

c. desorbing the absorbed carbon dioxide to regenerate the sorbent.

2. A regenerable carbon dioxide removal process as in claim 1, wherein said amine is 2-amino-2-methyl-1,3-propanediol, 2-hydroxyethyl piperazine, methyldiethanolamine, monoethanolamine, polyethylene imines, tetraethylenepentamine, triethanolamine, polyethylene imine, or mixtures thereof.

3. A regenerable carbon dioxide removal process as in claim 1, wherein said absorbed carbon dioxide is desorbed by heating said sorbent.

4. A regenerable carbon dioxide removal process as in claim 3, wherein said sorbent is heated to about 30°

C. to about 50 °

C.

5. A regenerable carbon dioxide removal process as in claim 3, wherein said absorbed carbon dioxide is desorbed by reducing the carbon dioxide partial pressure environment to below about 0.1 mm Hg.

6. A regenerable carbon dioxide removal process as in claim 5 wherein said carbon dioxide partial pressure is reduced by applying a vacuum and/or employing a carbon dioxide lean sweep gas.

7. A regenerable carbon dioxide removal process as in claim 1, wherein said polyol is dimethyl ether of polyethylene glycol, glycerol, methoxy triethylene glycol diacetate, polyethylene glycol, propylene carbonate, 1, 2-propylene glycol, a sugar alcohol, or mixtures thereof.