Method of preparation of a CO;removal sorbent with high chemical stability during multiple cycles

• US 9,079,160 B2
• Filed: 04/22/2013
• Issued: 07/14/2015
• Est. Priority Date: 04/22/2013
• Status: Active Grant

• Current Assignee: US Department of Energy (Government of the United States of America)
• Original Assignee: US Department of Energy (Government of the United States of America)
• Inventors: Siriwardane, Ranjani V., Rosencwaig, Shira
• Primary Examiner(s): ANTHONY, JOSEPH DAVID
• Application Number:
  US13/867,192
• Publication Number:
  US 20140312271A1
• Time in Patent Office: 813 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B01D 2251/304 of sodium
• CPC Class Codes: B01D 2251/604 Hydroxides
• CPC Class Codes: B01D 2252/20405 Monoamines
• CPC Class Codes: B01D 2252/20489 with two or more hydroxyl groups
• CPC Class Codes: B01D 2253/11 Clays
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• 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 53/52 Hydrogen sulfide
• CPC Class Codes: B01D 53/526 Mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01D 53/80 Semi-solid phase processes, i.e. by using slurries
• CPC Class Codes: B01J 20/04 comprising compounds of alkali metals, alkaline earth metals or magnesium
• CPC Class Codes: B01J 20/041 Oxides or hydroxides
• CPC Class Codes: B01J 20/043 Carbonates or bicarbonates, e.g. limestone, dolomite, aragonite
• CPC Class Codes: B01J 20/06 comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/12 Naturally occurring clays or bleaching earth
• CPC Class Codes: B01J 20/22 comprising organic material
• 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 20/30 Processes for preparing, regenerating, or reactivating
• CPC Class Codes: B01J 20/3204 Inorganic carriers, supports or substrates
• CPC Class Codes: B01J 20/3236 : containing metal, other than zeolites, e.g. oxides, hydroxides, sulphides or salts
• 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 2220/46 : Materials comprising a mixture of inorganic and organic materials materials coated or impregnated on a carrier B01J20/32
• 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

Abstract

Method for the production of a clay-alkali-amine CO₂ sorbent prepared by integrating a clay substrate, basic alkali salt, and amine liquid. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay substrate and basic alkali salt may be combined in a solid-solid heterogeneous mixture and followed by introduction of the amine liquid. Alternatively, an alkaline solution may be blended with the amine solution prior to contacting the clay substrate. The clay-alkali-amine CO₂ sorbent is particularly advantageous for low temperature CO₂ removal cycles in a gas stream having a CO₂ concentration less than around 2000 ppm and an oxygen concentration around 21%, such as air. Results are presented illustrating the performance of the clay-alkali-amine CO₂ sorbent compared to a clay-amine sorbent lacking the alkali inclusion.

Claims

1. A method of making a clay-alkali-amine CO₂ sorbent comprising:

supplying a clay substrate;

supplying a basic alkali salt, where the basic alkali salt is supplied at from about 1 part to about 50 parts per 100 parts of the clay substrate by weight;

supplying an amine liquid comprised of an amine, where the amine liquid is supplied at from about 1 part to about 10 parts per 10 parts of a clay-alkali combination by weight, where the clay-alkali combination is a combined proportion of the clay substrate and the basic alkali salt; and

integrating the clay substrate, the basic alkali salt, and the amine liquid, thereby producing the clay-alkali-amine CO₂ sorbent.

2. The method of claim 1 where the clay substrate is a plurality of clay substrate granules and where the basic alkali salt is a plurality of basic alkali salt granules, and where the integrating step is comprised of:

mixing the plurality of basic alkali salt granules and the plurality of clay substrate granules, thereby generating a solid-solid heterogeneous mixture; and

combining the solid-solid heterogeneous mixture and the amine liquid, thereby producing the clay-alkali-amine CO₂ sorbent.

3. The method of claim 2 where the plurality of clay substrate granules and the plurality of basic alkali salt granules has a mean diameter of less than 500 micron.

4. The method of claim 2 further comprised of adding liquid to the solid-solid heterogeneous mixture and forming porous clay-alkali pellets.

5. The method of claim 4 further comprised of subjecting the porous clay-alkali pellets to a temperature of at least 50°

C. for a period of at least 30 minutes.

6. The method of claim 4 where the integrating step is comprised of contacting the porous clay-alkali pellets and the amine liquid and allowing the amine liquid to penetrate some portion of the pores of the porous clay-alkali pellets, thereby producing the clay-alkali-amine CO₂ sorbent.

7. The method of claim 6 where a mean diameter of the porous clay-alkali pellets is less than 30 mm.

8. The method of claim 6 further comprised of drying the clay-alkali-amine CO₂ sorbent by subjecting the clay-alkali-amine CO₂ sorbent to a temperature of less than 120°

C. for a period of at least 30 minutes.

9. The method of claim 1 further comprised of adding an alkaline solution to the amine liquid, where the alkaline solution is comprised of a second basic alkali salt.

10. The method of claim 2 where the basic alkali salt is comprised of a metallic cation and an anion, where the metallic cation is Na, K, Li, Rb, Cs, Ca, Ba, or Sr and where the anion is hydroxide ion, a carbonate ion, a acetate ion, a phosphate ion, or an oxide

11. The method of claim 10 where the metallic cation is Na and the anion is the carbonate ion, and further comprised of adding an alkaline solution to the amine liquid, where the alkaline solution is comprised of a second basic alkali salt, where the second basic alkali salt is comprised of Na, and where a mass of the second basic alkali salt comprising the alkaline solution is less than about 30% of the mass of the amine comprising the amine liquid.

12. The method of claim 1 where the clay substrate is a plurality of porous clay pellets, and where the basic alkali salt is an alkali solution comprised of the basic alkali salt, and where a mass of the basic alkali salt comprising the alkali solution is less than about 30% of the mass of the amine comprising the amine liquid, and where the integrating step is comprised of:

blending the liquid amine, the alkali solution, and a solvent, where the basic alkali salt is soluble in the solvent, and where the solvent is soluble in the amine, thereby generating an amine-alkali liquid;

contacting the plurality of porous clay pellets and the amine-alkali liquid and allowing at least a portion of the amine alkali liquid to impregnate at least a portion of the plurality of porous clay pellets, thereby producing the clay-alkali-amine CO₂ sorbent.

13. The method of claim 12 where a mean diameter of the porous clay pellets is less than 30 mm.

14. The method of claim 12 further comprised of drying the clay-alkali-amine CO2 sorbent by subjecting the clay-alkali-amine CO₂ sorbent to a temperature of less than 120°

C. for a period of at least 30 minutes.

15. The method of claim 12 where the basic alkali salt is comprised of a metallic cation and an anion, where the metallic cation is Na, K, Li, Rb, Cs, Ca, Ba, or Sr and where the anion is hydroxide ion, a carbonate ion, a acetate ion, a phosphate ion, or an oxide ion.

16. The method of claim 15 where the metallic cation is Na and the anion is the carbonate ion.

17. A method of making a clay-alkali-amine CO₂ sorbent comprising:

supplying a clay substrate, where the clay substrate is a plurality of clay substrate granules;

supplying a basic alkali salt, where the basic alkali salt is comprised of a metallic cation and an anion where the metallic cation is Na, K, Li, Rb, Cs, Ca, Ba, or Sr and where the anion is hydroxide ion, a carbonate ion, an acetate ion, a phosphate ion, or an oxide ion, and where the basic alkali salt is a plurality of basic alkali salt granules, and where the basic alkali salt is supplied at from about 1 part to about 50 parts per 100 parts of the clay substrate by weight;

mixing the plurality of basic alkali salt granules and the plurality of clay substrate granules, thereby generating a solid-solid heterogeneous mixture;

adding water to the solid-solid heterogeneous mixture and forming porous clay-alkali pellets, where a mass of the water is less than 50% of a mass of the solid-solid heterogeneous mixture;

supplying an amine liquid comprised of an amine, where the amine liquid is supplied at from about 1 part to about 10 parts per 10 parts of a clay-alkali combination by weight, where the clay-alkali combination is a combined proportion of the clay substrate and the basic alkali salt;

contacting the porous clay-alkali pellets and the amine liquid and allowing the amine liquid to penetrate some portion of the pores of the porous clay-alkali pellets, thereby producing the clay-alkali-amine CO₂ sorbent.

18. The method of claim 17 further comprised of adding an alkaline solution to the amine liquid, where the alkaline solution is comprised of a second basic alkali salt, and where a mass of the second basic alkali salt comprising the alkaline solution is less than about 30% of the mass of the amine comprising the amine liquid.

19. The method of claim 18 further comprised of subjecting the porous clay-alkali pellets to a temperature of at least 50°

C. for a period of at least 30 minutes and further comprised of subjecting the clay-alkali CO₂ sorbent to a temperature of less than 120°

C. for a period of at least 30 minutes.

20. The method of claim 19 where the plurality of clay substrate granules and the plurality of basic alkali salt granules has a mean diameter of less than 500 micron, and where a mean diameter of the porous clay-alkali pellets is less than 30 mm.