WO2015080998A1

WO2015080998A1 - Laminates for rapid co2 capture from gas mixtures

Info

Publication number: WO2015080998A1
Application number: PCT/US2014/067052
Authority: WO
Inventors: Farid AKHTAR; Lennart Bergstrom; Steven Bolaji Ogunwumi
Original assignee: Corning Incorporated; Su Holding Ab
Priority date: 2013-11-26
Filing date: 2014-11-24
Publication date: 2015-06-04

Abstract

According to various embodiments, a laminated adsorbent for use in a swing adsorption process includes at least one sheet including a microporous adsorbent. The sheet has a thickness that is less than or equal to about 1,000 micrometers and includes less than about 5 wt % of a non-porous material. The laminated adsorbent has a macroporosity of less than about 40%. The microporous adsorbent may be one of an aluminosilicate, a metal organic framework, an aluminophosphate, or combinations thereof. In some embodiments, the laminated adsorbent is substantially free of binders.

Description

LAMINATES FOR RAPID CO? CAPTURE FROM GAS MIXTURES

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 61/908982 filed on November 26, 2013 the contents of which is incorporated herein by reference in its entirety .

BACKGROUND FIELD

[0002] The present specification generally relates to laminates for separation of a gas from a gas mixture and, more specifically, to thin, binderless laminates for use in rapid swing adsorption processes.

TECHNICAL BACKGROUND

[0003] A variety of opportunities exist in the market that require the separation of CO₂ from natural gas or other gas streams. For example, some opportunities may monetize CO₂ while other opportunities focus on minimizing the carbon footprint to the environment. However, conventional gas separation technologies are often expensive, both in terms of operational costs and capital costs, or do not yield the desired throughput.

[0004] In conventional swing adsorption processes, a feed gas stream is passed over an adsorbent having an affinity for the gas to be separated out. However, the adsorbents often include an inorganic binder to hold together the sorbent particles, which decreases the overall efficiency of the adsorbent. Additionally, conventional adsorbents may include large macroporous voids which further decrease the separation efficiency of the adsorbent. [0005] Accordingly, a need exists for alternative adsorbents capable of a reasonable throughput, and which have a small footprint, are cost-effective to manufacture and operate, and overcome the mass transfer constraints of conventional adsorbents.

SUMMARY

[0006] According to one embodiment, a laminated adsorbent includes at least one sheet including a microporous adsorbent. The at least one sheet has a thickness that is less than or equal to about 1,000 micrometers. The at least one sheet includes less than or equal to about 5 wt % of a non-porous material. The laminated adsorbent has a macroporosity of less than or equal to about 40%.

[0007] In another embodiment, method of making a laminated adsorbent includes heating, in a graphite die, microporous adsorbent particles to a target temperature by passing a pulsed current through the graphite die. Once the target temperature is reached, the method includes holding the target temperature for about 5 minutes or less. The method further includes applying a pressure to the microporous adsorbent particles during the heating and the holding to consolidate the adsorbent particles into a sheet of the laminated adsorbent. Finally, the method includes post-treating the sheet in a precursor solution including additional microporous adsorbent particles to synthesize adsorbent within the macropores in the sheet, thereby reducing the macroporosity of the sheet while maintaining an adsorption capacity of the laminated adsorbent sheet.

[0008] In yet another embodiment, a method of separating a gas from a mixture of gases includes passing the mixture of gases over a laminated adsorbent having an affinity for the gas to be separated from the mixture of gases; adsorbing, using the laminated adsorbent, the gas to be separated from the mixture of gases while a resultant portion of the mixture of gases passes through the laminated adsorbent; and reducing the pressure around the laminated adsorbent to release the gas adsorbed using the laminated adsorbent. The gas is passed over the laminated adsorbent under pressure. The laminated adsorbent includes at least one sheet including a microporous adsorbent. The sheet has a thickness of less than or equal to about 1,000 micrometers, and includes less than or equal to about 5 wt % of a non-porous material.

[0009] Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings.

[0010] It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 schematically depicts a rapid swing apparatus including a laminated adsorbent for use in a rapid swing adsorption process, according to one or more embodiments shown or described herein; [0012] FIG. 2 depicts an SEM micrograph showing the micro structure of a laminate before a hydrothermal process (Fig. 2A) and after a hydrothermal process (Fig. 2B), according to one or more embodiments shown or described herein;

[0013] FIG. 3 is a plot illustrating the relationship between thickness and biaxial strength of a laminate, according to one or more embodiments shown or described herein; and

[0014] FIG. 4A to 4D are plots graphically depicting the change in CO2 adsorption kinetics as a function of the thickness of a laminate, according to one or more embodiments shown or described herein.

DETAILED DESCRIPTION

[0015] Reference will now be made in detail to various embodiments of absorbents having a laminate structure, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. One embodiment of a rapid swing adsorption process using a laminated adsorbent is shown in FIG. 1, and is designated generally throughout by the reference numeral 100. The laminated adsorbent may generally include at least one sheet comprising a microporous adsorbent. The sheet has a thickness that is less than or equal to about 1000 micrometers and includes less than or equal to about 5 wt % of a non-porous material. The laminated adsorbents and rapid swing adsorption processes using the laminated adsorbents will be described in more detail herein with specific reference to the appended drawings.

[0016] Referring now to FIG. 1, a rapid swing apparatus 100 for use in a rapid swing adsorption process is schematically depicted. The rapid swing apparatus 100 generally includes a vessel 106 having an inlet side 104 and an outlet side 1 10. A laminated adsorbent 108 is disposed in the vessel 106 between the inlet side 104 and the outlet side 1 10. The laminated adsorbent 108 is positioned in the vessel 106 such that a feed gas 102 entering the inlet side 104 of the vessel 106 passes through the laminated adsorbent 108 before exiting the vessel 106 at the outlet side 1 10 of the vessel 106.

[0017] In the rapid swing adsorption process, the feed gas 102 is passed into the inlet side 104 of the vessel 106. The feed gas 102 may generally comprise a mixture of gases from which at least one gas is to be separated. For example, in some embodiments, the feed gas 102 may be a stream of gas which primarily includes natural gas in addition to one or more secondary gases, such as CO₂. In these embodiments, the rapid swing apparatus 100 may be used to separate the CO₂ from the natural gas. While the separation of C02 from natural gas is one exemplary use for the rapid swing apparatus 100, it should be understood that rapid swing apparatus 100 may be used for other gas separation processes such as, for example, the separation of oxygen from air, as in the case of portable oxygen concentrators.

[0018] After entering the inlet side 104 of the vessel 106, the feed gas 102 is passed over the laminated adsorbent 108. The laminated adsorbent 108 is constructed from materials which have an affinity for the gas to be separated from the feed gas. For example, where CO2 is to be separated from the feed gas 102, the laminated adsorbent 108 has an affinity for CO₂. Although CO₂ is used as an exemplary gas to be separated, it should be understood that other gases may be separated from other gas mixtures depending on the affinity of the laminated adsorbent 108.

[0019] In various embodiments, the feed gas 102 is passed over the laminated adsorbent 108 while the temperature, pressure, and/or flow is cycled between a first temperature, pressure, and/or flow and a second temperature, pressure, and/or flow. Adsorption of at least one gas may occur at the first temperature, pressure, and/or flow while desorption of the gas occurs at the second temperature, pressure, and/or flow. For example, the feed gas 102 may be passed over the laminated adsorbent 108 under pressure. The pressure may be, for example, greater than atmospheric pressure. As the pressure increases, the gases in the feed gas 102 tend to be attracted to solid surfaces, such as the surface of the laminated adsorbent 108, and the rate of adsorption increases. Separation of the secondary gas, such as CO2, from the feed gas 102 occurs because the secondary gas has a greater attraction to surface of the laminated adsorbent 108 relative to the balance of the feed gas 102. As such, the secondary gas or gases may become "trapped" in the laminated adsorbent 108 while the balance of the feed gas that is not adsorbed pass through the laminated adsorbent 108 and into an outlet side 1 10 of the vessel 106. The secondary gases adsorbed by the laminated adsorbent 108 stay within the laminated adsorbent 108 until they are subsequently discharged through a desorption process.

[0020] The resultant portion 112 of the gas mixture (i.e., the feed gas 102 less the secondary gases trapped in the laminated adsorbent 108) exits the vessel 106. The resultant portion 1 12 may be exhausted from the outlet side 110 of the vessel 106 as a waste gas, or it may be condensed in another vessel positioned downstream of the vessel 106. For example, the resultant portion 112 may be concentrated and monetized separately, as in the case of natural gas.

[0021] In order to maintain the adsorbent capability of the laminated adsorbent 108, the laminated adsorbent 108 may be periodically regenerated. The laminated adsorbent 108 may be regenerated, for example, by decreasing the pressure within the vessel 106 around the laminated adsorbent 108, increasing the temperature within the vessel 106, and/or altering a flow passed over the laminated adsorbent 108. In some embodiments, the laminated adsorbent 108 may be regenerated by exposing the laminated adsorbent 108 to microwaves. In various embodiments, when the laminated adsorbent 108 is regenerated, the gas adsorbed by the laminated adsorbent 108 is released. The released gas may be exhausted from the vessel 106 through the inlet side 104 or the outlet side 110 of the vessel 106, depending on the particular embodiment. The gas may be condensed in another vessel or exhausted as a waste gas, depending on the particular implementation. Similar to the resultant portion 1 12, the released gas may be concentrated and monetized. For example, CO2 may be sold for use in enhanced oil recovery or other operations requiring CO₂.

[0022] A cycle of the rapid swing adsorption process may take less than about five minutes to adsorb and regenerate. However, in some embodiments, the cycle time may be from about 1 minute to about 10 minutes. In some embodiments, the cycle may take less than about two minutes or less than about one minute. Accordingly, in some embodiments, the rapid swing adsorption process 100 may include two vessels 106, such that while one laminated adsorbent 108 is adsorbing gas, another laminated adsorbent 108 is regenerating.

[0023] In embodiments in which the cycle time is less than 2 minutes, the laminated adsorbent 108 may be selected in order to overcome mass transfer constraints, have a low backpressure, a low attrition, and offer some heat transfer advantage.

[0024] In various embodiments, the laminated adsorbent 108 includes at least one sheet that includes a microporous adsorbent material. As used herein, the phrase "microporous adsorbent" refers to an adsorbent material that contains pores with diameters less than about 2nm. The microporous adsorbent may be an aluminosilicate (such as a zeolite), a metal organic framework, an aluminophosphate (A1PO), a zeolite imidazolate framework (ZIF), a carbon, an alkali or alkali earth oxide, a lithium zirconate, a clay (hydrotalcite-like adsorbent), and/or combinations thereof. In some embodiments, polyethyleneimine (PEI) and PEI hybrids may be used as microporous adsorbents. The microporous adsorbent utilized may vary depending on the particular gas to be separated from the gas mixture, and the ability of the laminate to adsorb the gas in rapid swing separation processes.

[0025] It has been found that the addition of non-porous materials and binders to the at least one sheet of the laminated adsorbent 108 may reduce the adsorbent capacity of the laminated adsorbent 108, thereby decreasing process efficiency. As such, in the embodiments described herein, the addition of non-porous materials and binders is limited in order to improve both capture efficacy and efficiency. Accordingly, in various embodiments, in order to increase the adsorbent capacity of the at least one sheet of the laminated adsorbent 108, the at least one sheet includes less than or equal to about 5 wt % of a non-porous material. Non-porous materials can include materials that are substantially free of pores, such as amorphous and inorganic colloidal binders, inorganic whiskers or fibers, metals and other materials conventionally used in membrane forming methods. In some embodiments, the sheet may include less than or equal to about 2 wt % of the non-porous material, less than or equal to about 1 wt % of the non-porous material, or may be substantially free of non- porous material. The sheet may also be substantially free of binders which similarly reduce capture efficacy and efficiency. For example, in some embodiments, no additional binder material may be added to the microporous adsorbent material during formation of the sheet.

[0026] In addition, in various embodiments, the laminated adsorbent 108 has a low macroporosity in order to accommodate fast mass transfer kinetics. As used herein, the term macroporosity refers to the presence of cavities between particles that are larger than or equal to about 50 nm. In various embodiments, the laminated adsorbent 108 has a macroporosity of less than or equal to about 40%. In some embodiments, the macroporosity of the laminated adsorbent is less than or equal to about 27%. [0027] In various embodiments, multiple sheets of microporous adsorbent material may be layered to form the laminated adsorbent 108. The sheets may be made from the same microporous adsorbent or from different microporous adsorbents, resulting in a composite of microporous adsorbents for removal of at least one secondary gas component from a feed gas 102. For example, a first sheet may be made of an aluminosilicate microporous adsorbent and a second sheet may be made of an aluminophosphate microporous adsorbent. As another example, both sheets may be made from different aluminosilicate microporous adsorbents (e.g., zeolite Y and zeolite 13X). In yet another example, a composite result when single sheets are made from multiple microporous adsorbents. In various embodiments, the sheets are layered directly on one another, without the inclusion of spacers or flow channels between adjacent sheets.

[0028] In order to maintain the fast mass transfer capability while limiting the amount of backpressure, each sheet of the microporous adsorbent material may be thin. For example, in various embodiments, each sheet of microporous adsorbent material has a thickness that is less than or equal to about 1000 micrometers. In some embodiments, the thickness of each sheet of microporous adsorbent material is less than or equal to about 400 micrometers.

[0029] Though each sheet in the laminated adsorbent 108 is thin, in various embodiments, the laminated adsorbent 108 has a biaxial tensile strength that is greater than or equal to about 1.2 MPa. The biaxial tensile strength, a measure of the strength of the laminated adsorbent 108 in width and length directions, may be determined according to one of a variety of known methods. For example, a piston-on-three-ball test or a piston-on-ring test may be used to determine the biaxial tensile strength of the laminated adsorbent 108. In some embodiments, the biaxial tensile strength of the laminated adsorbent 108 is greater than or equal to about 2 MPa. [0030] In various embodiments, each sheet of the laminated adsorbent 108 may be made via pulsed current processing (PCP) (i.e., spark plasma sintering). For example, adsorbent particles may be placed in graphite dies of a spark plasma sintering machine. Depending on the temperature, at least some of the adsorbent particles may be sintered together, resulting in a stronger sheet. In various embodiments, substantially no binder is added to the adsorbent particles. A pulsed DC current is then passed through the graphite dies, and the graphite dies and adsorbent particles are heated at a heating rate from about 50 °C min ¹ to about 100 °C min^"1 up to a target temperature. In embodiments, the target temperature may be from about 500 °C to about 600 °C. In embodiments, the target temperature may be held from about 3 minutes to about 5 minutes. A pressure from about 20 MPa to about 50MPa may be applied during heating and holding cycles. As such, in various embodiments, adsorbent particles can be consolidated from a layer with a thickness of about 600 micrometers to about 800 micrometers to a laminated adsorbent having a thickness of about 300 micrometers. The temperature within the graphite dies may be measured using a K-type thermocouple or other suitable temperature measurement device. The consolidation of the adsorbent particles may be monitored by following a position of a plunger coupled to the graphite dies of the spark plasma sintering machine. The result of the consolidation is a sheet of the self-supporting laminated adsorbent 108.

[0031] In some embodiments, the macroporosity of the laminated adsorbent 108 may be further tailored after the PCP. For example, hydrothermal treatment of a precursor solution of microporous adsorbent positioned in the macropores of the laminated adsorbent 108 may be used to synthesize adsorbent within the macropores, thereby decreasing the porosity of the laminated adsorbent 108. In some embodiments, the laminated adsorbent 108 may be post- treated at about 70 °C in a precursor solution of the microporous adsorbent that was used to form the laminated adsorbent 108 for about 3 hours. The macroporosity may be reduced while the adsorption capacity of the laminated adsorbent 108 is retained.

Examples

[0032] Various embodiments will be further clarified by the following examples. It should be understood that while the following examples include zeolite 13X as the microporous adsorbent, other microporous adsorbents may be employed.

EXAMPLE 1

[0033] NaX zeolite powders including particles having sizes of about 1-2μιη and about 3- 5μιη were consolidated into 13X zeolite laminates by PCP. No additional binder was added, and the amount of amorphous, non-porous materials was below about 2%. Consolidation was performed in a Dr. Sinter 2050 spark plasma sintering machine (Sumitomo Coal Mining Co., Ltd., Japan) by electric heating driven by an alternating current combined with compressive stress. The powder bodies were heated in graphite dies at a heating rate from about 50 °C min ¹ to about 100 °C min ¹ up to a targeted temperature between 500-600 °C. The temperature was held for about 3 to about 5 minutes. A pressure of about 20 to about 50 MPa was applied during the heating and holding cycles. Table 1 shows the characteristics of laminates with a thickness of about 600 μιη and about 300 μιη.

Laminate 570 550 20 0.24 0.92 2.4 39 4.7 (0.6 mm)

Laminate 643 ± 610 ± 50 34 ± 4 0.29 0.65 ± 2.8 ± 39.5 ± 4.8 ± 0.3 (0.3 mm) 50 0.1 0.6 0.5

Table 1 : Textural properties, average micropore size, total macropore area, porosity and CO2 adsorption capacity of 13X laminates.

[0034] In Table 1, the BET surface area, t-plot micropore area, external surface area, and micropore volume values are determined from 2 adsorption at 77 K. The median macropore diameter, total macropore area, and porosity values were determined from mercury intrusion porosimetry.

[0035] The macroporosity of the laminate was tailored by hydrothermal treatment. The laminate was post-treated at 70 °C in a precursor solution of zeolite 13X for about 3 hours. The macroporosity was reduced from about 40% to about 27%, and the CO2 adsorption capacity remained at about 4.3 mmol/g or above following treatment. FIG. 2 is an SEM micrograph confirming the post crystalline microstructure of the laminate after the hydrothermal treatment process (panel b) as compared with the microstucture of the laminate before the hydrothermal treatment process (panel a). Table 2 illustrates the change in average pore diameter, total macropore area, porosity, and CO2 adsorption of the laminate before and after hydrothermal treatment.

Average Total Porosity (%) CO2 adsorption macropore macropore area capacity at 20 °C diameter (μιη) (m²/g) (mmol/g)

Laminate 1 0.7 4 40 4.5

Laminate 1 after 0.7 1.3 27 4.3

HT treatment

Table 2 : Change in average pore diameter, total macropore area, porosity and C02 adsorption capacity of laminates via a hydrothermal treatment to synthesize zeolite 13X within macropores.

EXAMPLE 2

[0036] The mechanical strength and CO2 uptake kinetics of zeolite 13X laminates having various thicknesses were compared. FIG. 3 is a plot illustrating the relationship between the mechanical strength and the thickness of the laminate. The biaxial tensile strength was measured using a piston-on-3-ball test. As shown in FIG. 3, zeolite 13X laminates having a thickness of about 300 micrometers have a biaxial tensile strength of about 2 MPa. The biaxial tensile strength increases with increasing thickness, and is above about 3.4 MPa for laminates having a thickness greater than about 500 micrometers.

[0037] FIG. 4 is a plot illustrating CO2 uptake kinetics of zeolite 13X laminates of varying thicknesses. In particular, the CO2 uptake kinetics of zeolite 13X laminates having thicknesses of 350 micrometers, 450 micrometers, 600 micrometers, and 750 micrometers are shown. The CO2 uptake kinetics were determined using a thermo gravimetric analyzer (TGA). As shown in FIG. 4, laminates with a thickness of 350 micrometers show faster CO2 adsorption compared to the thicker laminates at initial times for the second cycle, where physisorption dominates. The uptake for the thin laminate is fast during the first 5-10 seconds. This may be advantageous for a rapid swing adsorption process. [0038] It should now be understood that various embodiments described herein may enable the separation of CO₂ or other gases from gas streams in a rapid and efficient manner. The laminated adsorbent according to various embodiments may be used in ultra-rapid swing adsorption processes, potentially decreasing the cycle time and increasing throughput compared to conventional methods. In addition, the laminated adsorbent may be formed as a skid for use outside of a plant, increasing mobility and decreasing costs associated with gas separation. Furthermore, various embodiments of the laminated adsorbent exhibit high CO₂ adsorbent capability, which may be used to provide more space-efficient gas storage when compared to conventional extrusion storage methods.

[0039] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus it is intended that the specification cover the modifications and variations of the various embodiments described herein provided such modification and variations come within the scope of the appended claims and their equivalents.

Claims

What is claimed is:

1. A laminated adsorbent comprising at least one sheet comprising a microporous adsorbent, wherein:

the at least one sheet has a thickness that is less than or equal to about 1000 micrometers;

the at least one sheet comprises less than about 5 wt % of a non-porous material; and the laminated adsorbent has a macroporosity of less than about 40%.

2. The laminated adsorbent according to claim 1, wherein the thickness of the at least one sheet is less than or equal to about 400 micrometers.

3. The laminated adsorbent according to claim 1 or claim 2, wherein the microporous adsorbent comprises one of an aluminosilicate, a metal organic framework, an aluminophosphate, and combinations thereof.

4. The laminated adsorbent according to any of the preceding claims, wherein the at least one sheet comprises less than about 2 wt % of the non-porous material.

5. The laminated adsorbent according to claim 4, wherein the at least one sheet comprises less than about 1 wt % of the non-porous material.

6. The laminated adsorbent according to claim 5, wherein the at least one sheet is substantially free of the non-porous material.

7. The laminated adsorbent according to any of the preceding claims, wherein the at least one sheet is substantially free of binders.

8. The laminated adsorbent according to any of the preceding claims, wherein the macroporosity of the laminated adsorbent is less than about 27%.

9. The laminated adsorbent according to any of the preceding claims, wherein the laminated adsorbent has a biaxial tensile strength greater than about 1.2 MPa.

10. The laminated adsorbent according to claim 9, wherein the biaxial tensile strength of the laminated adsorbent is greater than or equal to about 2 MPa.

1 1. The laminated adsorbent according to any of the preceding claims, wherein the laminated adsorbent comprises a first sheet comprising a first microporous adsorbent and a second sheet comprising a second microporous adsorbent, wherein:

the first microporous adsorbent differs from the second microporous adsorbent; and the first sheet and the second sheet are layered to provide a composite laminated adsorbent.

12. A method of making a laminated adsorbent, the method comprising:

heating, in a graphite die, microporous adsorbent particles to a target temperature by passing a pulsed current through the graphite die;

holding the target temperature for about 5 minutes or less;

applying a pressure to the microporous adsorbent particles during the heating and the holding to consolidate the adsorbent particles into a sheet of the laminated adsorbent; and post-treating the sheet in a precursor solution comprising additional microporous adsorbent particles to synthesize adsorbent within macropores in the sheet, thereby reducing a macroporosity of the sheet while maintaining an adsorption capacity of the sheet of the laminated adsorbent.

13. The method according to claim 12, applying the pressure comprising applying a pressure from about 20 MPa to about 50 MPa.

14. The method according to claim 12 or claim 13, wherein the post-treating reduces the macroporosity of the sheet from greater than or equal to about 40% to about 27%.

15. The method according to any of claims 12 to 14, wherein:

the microporous adsorbent particles comprise at least one of an aluminosilicate, a metal organic framework, a zeolite imidazolate framework, a carbon, an alkali or alkali earth oxide, a lithium zirconate, a clay, an aluminophosphate, and combinations thereof; and

substantially no binder is added to the microporous adsorbent particles.

16. A method of separating a gas from a mixture of gases, the method comprising:

passing, under pressure, the mixture of gases over a laminated adsorbent having an affinity for the gas to be separated from the mixture of gases, wherein the laminated adsorbent comprises at least one sheet comprising a microporous adsorbent, the at least one sheet having a thickness that is less than or equal to about 1,000 micrometers, and the at least one sheet comprises less than about 5 wt % of a non-porous material; adsorbing, using the laminated adsorbent, the gas to be separated from the mixture of gases while a resultant portion of the mixture of gases passes through the laminated adsorbent; and

reducing the pressure around the laminated adsorbent to release the gas adsorbed using the laminated adsorbent.

17. The method of claim 16, wherein the gas to be separated from the mixture of gases comprises CO2.

18. The method of claim 16 or claim 17, wherein the laminated adsorbent is in the form of a plate.

19. The method of any of claims 16 to 18, wherein the at least one sheet comprises less than about 2 wt % of the non-porous material.

20. The method of any of claims 16 to 19, further comprising applying microwaves to the laminated adsorbent to regenerate the laminated adsorbent.