HYDRATED POROUS MATERIALS FOR SELECTIVE CO2 CAPTURE

• US 20180008957A1
• Filed: 07/03/2017
• Published: 01/11/2018
• Est. Priority Date: 08/25/2015
• Status: Active Grant

• Current Assignee: Rice University
• Original Assignee: Rice University
• Inventors: Tour, James M., Jalilov, Almaz S.
• Granted Patent: US 10,232,343 B2
• Time in Patent Office: Days
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2253/306 Surface area, e.g. BET-specific surface
• CPC Class Codes: B01D 2253/311 Porosity, e.g. pore volume
• CPC Class Codes: B01D 2256/24 Hydrocarbons
• CPC Class Codes: B01D 2256/245 Methane
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/025 with wetted adsorbents; Chromatography analytical chromatography G01N30/00 - G01N30/96; for liquids B01D15/08
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01J 20/20 comprising free carbon; comprising carbon obtained by carbonising processes
• CPC Class Codes: B01J 20/28073 being in the range 0.5-1.0 ml/g
• CPC Class Codes: B01J 20/28076 being more than 1.0 ml/g
• CPC Class Codes: B01J 20/3085 Chemical treatments not covered by groups B01J20/3007 - B01J20/3078
• CPC Class Codes: C10L 2290/542 Adsorption of impurities during preparation or upgrading of a fuel
• CPC Class Codes: C10L 3/104 Carbon dioxide
• 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

In some embodiments, the present disclosure pertains to methods of capturing CO₂ from an environment by hydrating a porous material with water molecules to the extent thereby to define a preselected region of a plurality of hydrated pores and yet to the extent to allow the preselected region of a plurality of pores of the porous material to uptake gas molecules; positioning the porous material within a CO₂ associated environment; and capturing CO₂ by the hydrated porous material. In some embodiments, the pore volume of the hydrated porous material includes between 90% and 20% of the pre-hydrated pore volume to provide unhydrated pore volume within the porous material for enhanced selective uptake of CO₂ in the CO₂ associated environment. In some embodiments, the step of capturing includes forming CO₂-hydrates within the pores of the porous material, where the CO₂·n/H₂O ratio is n<4.

Claims

1. A method of capturing CO₂ from an environment, the method comprising:

hydrating a porous material with water molecules to the extent thereby to define a preselected region of a plurality of hydrated pores and yet to the extent to allow the preselected region of a plurality of pores of the porous material to uptake gas molecules;

positioning the porous material within a CO₂ associated environment; and

capturing CO₂ by the hydrated porous material.

2. The method of claim 1, wherein the porous material comprises a plurality of nucleophilic moieties.

3. The method of claim 1, wherein the hydrating step comprises imbibing a plurality of pores of a predefined region of the porous material with water molecules.

4. The method of claim 1, wherein prior to the step of hydrating the porous material, pore volume of the porous material comprises at least 0.5 cm³/g to thereby define a pre-hydrated pore volume, and wherein after the step of hydrating the porous material, the pore volume of the hydrated porous material comprises less than 90% of the pre-hydrated pore volume thereby to provide unsaturated pores of the porous material and enhanced for selective uptake of the CO₂ in the CO₂ associated environment.

5. The method of claim 4, further comprising reducing saturation of the pores to a value less than 100%.

6. The method of claim 5, wherein the pore volume of the hydrated porous material comprises between 90% and 20% of the pre-hydrated pore volume to provide unhydrated pore volume within the porous material for enhanced selective uptake of CO₂ in the CO₂ associated environment.

7. The method of claim 4, further comprising the step of determining pore volume by porosimetry measurements.

8. The method of claim 1, further comprising forming one or more ordered matrices within the pores, the one or more ordered matrices comprising gas-hydrates.

9. The method of claim 1, wherein the step of capturing includes forming CO₂-hydrates within the pores of the porous material, and wherein the CO₂·

n/H₂O ratio is n<

4.

10. The method of claim 3, wherein the water molecules comprise a form of gas hydrates positioned within the plurality of pores.

11. The method of claim 3, wherein the water molecules are associated with water soluble additives.

12. The method of claim 11, wherein the water soluble additives are selected from the group consisting of salts, bases, organic solvents, organic amines, fluorocarbons, small molecules, oligomers, polymers, and combinations thereof.

13. The method of claim 1, wherein the porous material has a CO₂ capture capacity of about 50% to about 250% of the porous material weight.

14. The method of claim 1, wherein the molar ratio of captured CO₂ over captured hydrocarbon in porous material ranges from 10 to about 250.

15. The method of claim 1, wherein the molar ratio of captured CO₂ over captured hydrocarbons in the porous carbon material is more than 200.

16. The method of claim 1, wherein the porous material is selected from the groups consisting of porous organic frameworks, metal-organic frameworks, zeolites, molecular sieves, porous carbon materials, and combinations thereof.

17. The method of claim 1, wherein the porous material is a porous carbon material.

18. The method of claim 1, wherein CO₂ associated environment comprises a natural gas stream that also contains water vapor.

19. The method of claim 1, wherein the capture of CO₂ by the hydrated pores of the porous material occurs selectively over hydrocarbons in the environment.

20. The method of claim 1, further comprising a step of releasing the captured CO₂ from the porous material thereby to maintain hydration within the porous material.

21. The method of claim 20, further comprising a step of reusing the plurality of hydrated pores of the porous material after the releasing to capture additional CO₂ from an environment.

22. The method of claim 1, wherein the porous material comprises ultra-high surface area porous carbon material.