Flexible sorptive polymer composite articles having adsorption and desorption configurations

Abstract

To provide a good composite sorptive polymer composite article and the like.SOLUTION: Composite sorptive polymer composite articles for adsorption are disclosed. The sorbent polymer composite article comprises a sorbent and a flexible porous polymer, wherein the sorbent polymer composite article has an adsorption configuration in which the sorbent polymer composite article is configured to adsorb one or more components of a feed stream and a desorption configuration in which the sorbent polymer composite article is configured to remove the one or more components from the sorbent polymer composite article.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 157,451, filed March 5, 2021, and U.S. Provisional Application No. 63 / 302,852, filed January 25, 2022, the disclosures of each of which are incorporated herein by reference in their entirety.

[0002] Field The present disclosure relates to sorptive polymer composite articles, methods of forming sorptive polymer composite articles, and methods of using sorptive polymer composite articles for adsorption purposes, including adsorption for direct air capture (DAC) of carbon dioxide. [Background technology]

[0003] background Rising carbon dioxide (CO2) levels due to greenhouse gas emissions have been shown to be harmful to the environment. As reported in the Climate.gov article “Climate Change: Atmospheric Carbon Dioxide,” the average CO2 level in the atmosphere in 2019 was 409.8 ppm, the highest level recorded in the past 800,000 years. The rate at which atmospheric CO2 is increasing is also much higher than in previous decades.

[0004] To limit climate change to acceptable levels, it is necessary to not only reduce CO2 emissions to zero but to make them negative in the near future. Several possibilities exist to achieve negative emissions, such as the combustion of biomaterials to generate electricity, combined with CO2 capture from combustion flue gases and subsequent CO2 sequestration ("BECCS") or direct air capture of CO2 ("DAC").

[0005] Gas separation by adsorption has many different applications in industry, such as the removal of specific components from gas streams, where the desired product can be either the component removed from the gas stream, the remaining depleted stream, or both. This allows both minor and major components of the gas stream to be subjected to the adsorption process. One important gas separation application is in the recovery of CO2 from gas streams such as flue gas, exhaust gas, industrial waste gas, biogas, and atmospheric air. Air can be considered a dilute feed stream for CO2.

[0006] Direct capture of CO2 from the atmosphere, known as DAC, is one of several means of mitigating anthropogenic greenhouse gas emissions and has attractive economic prospects as a non-fossil, site-independent source of CO2 for commodity markets and the production of synthetic fuels. Specific advantages of capturing CO2 from the atmosphere include: a) DAC can address the emissions of distributed sources (e.g., land, sea, and air vehicles), which account for a large proportion of global greenhouse gas emissions and which cannot currently be captured at the emission site in an economically viable manner; b) DAC can address conventional emissions and therefore can produce truly negative emissions; and c) DAC systems do not need to be attached to the emission source and are site-independent, meaning they can be installed at the site where the CO2 is further processed or used.

[0007] There is a growing drive to develop and improve these processes to make them more efficient, maximizing the amount of CO2 removed from the atmosphere while minimizing the energy required in the process.

[0008] FIG. 1 is a schematic diagram of the process involved in a conventional DAC system 10. An inlet feed stream 11 containing a mixture of CO2 molecules 16 in a non-CO2 diluent 18 is provided. For example, the inlet feed stream 11 can be an air stream. During the adsorption process, the inlet feed stream 11 is exposed to a sorbent 12. The CO2 molecules 16 adsorb onto the sorbent 12, while the non-CO2 diluent 18 passes through the sorbent 12 and is exhausted from the system 10. The sorbent 12 then undergoes a desorption process to release the CO2 molecules 16 from the sorbent 12. The desorption process can involve moisture in the form of liquid water or water vapor, or a change in system temperature due to a reaction or energy supplied to the system. This desorption process is referred to as "swing" adsorption to define the cyclical process of repeated CO2 adsorption and desorption. If moisture swing adsorption is used, the sorbent 12 can be exposed to moisture in the form of water vapor or liquid water, causing the CO2 molecules 16 to desorb. If temperature swing adsorption is used, heat can be applied to the sorbent 12 to cause desorption of the CO2 molecules 16. These moisture and / or temperature fluctuations can temporarily break the bonds holding the molecules to the sorbent 12, thereby releasing the CO2 molecules 16. The desorbed CO2 molecules 16 can then be separated from the sorbent 12 and collected as product 14. The collected CO2 molecules 16 can then be concentrated and subjected to further necessary processing before being used or stored. It is important that the sorbent 12 used be able to repeatedly withstand the environment required to separate the CO2 molecules 16, e.g., high temperature and humidity conditions.

[0009] Established literature and techniques exist for DAC. One example is the use of an article that includes a substrate, such as a monolith, that can support or be coated with a sorbent material. Varying the type of substrate and the sorbent used establishes variations. However, these previously established literature and methods are limited in their ability to efficiently cycle between adsorption and desorption states. They also have limitations regarding the durability of the article. Additionally, the article may degrade when exposed to environments with high temperatures or high humidity levels, or a combination thereof, potentially resulting in a shortened lifespan. Summary of the Invention

[0010] Abstract A sorbent polymer composite article for adsorption is disclosed, the sorbent polymer composite article comprising a sorbent and a flexible porous polymer, the sorbent polymer composite article having an adsorption configuration, in which the sorbent polymer composite article is configured to adsorb one or more components from an input, and a desorption configuration, in which the sorbent polymer composite article is configured to remove one or more components from the sorbent polymer composite article.

[0011] According to one example ("Example A"), a sorbent polymer composite article includes a flexible composite of a sorbent and a flexible porous polymer, the sorbent polymer composite article having an adsorption configuration, in which the sorbent polymer composite article is configured to adsorb one or more components from a feed stream, and a desorption configuration, in which the sorbent polymer composite article is configured to remove one or more components from the sorbent polymer composite article. The flexibility of the flexible porous polymer facilitates transformation between the adsorption configuration and the desorption configuration.

[0012] According to a second example ("Example B"), a method of using a sorbent polymer composite article includes the steps of providing a sorbent polymer composite article having a porous composite portion comprising a sorbent and a flexible porous polymer; exposing the sorbent polymer composite article in a first configuration to a feed stream comprising carbon dioxide; adsorbing at least a portion of the carbon dioxide onto the sorbent while the sorbent polymer composite article is in the first configuration; placing the sorbent polymer composite article in a second configuration after the adsorption step; and desorbing carbon dioxide from the sorbent polymer composite article while the sorbent polymer composite article is in the second configuration. [Brief explanation of the drawings]

[0013] BRIEF DESCRIPTION OF THE DRAWINGS [Figure 1] Figure 1 is a schematic diagram of the processes involved in a DAC system.

[0014] [Figure 2] FIG. 2 is an elevational view of a first sorbent polymer composite article of the present disclosure.

[0015] [Figure 2A] FIG. 2A is a schematic elevational view of a first composite region of the first composite article of FIG.

[0016] [Figure 2B] 2B is a schematic elevational view of the first composite region of the first composite article of FIG. 2 in a compressed form.

[0017] [Figure 2C] FIG. 2C is a schematic elevational view of the first composite region of the first composite article of FIG. 2B in a further compressed form.

[0018] [Figure 2D] FIG. 2D is an elevational view of the first sorbent polymer composite article of FIG. 2 shown including an edge seal region of the present disclosure.

[0019] [Figure 3] FIG. 3 is a flow chart illustrating a method of using the sorbent polymer composite article of FIG.

[0020] [Figure 4A] FIG. 4A is a perspective view of a sorbent polymer composite article in a first layered configuration.

[0021] [Figure 4B] FIG. 4B is an elevational view of the sorbent polymer composite article of FIG. 4A in a second, rolled configuration.

[0022] [Figure 4C] FIG. 4C is a side view of a sorbent polymer composite article in a first layered configuration according to another embodiment disclosed herein.

[0023] [Figure 4D] FIG. 4D is an elevational view of the sorbent polymer composite article of FIG. 4C in a second, rolled configuration.

[0024] [Figure 5] FIG. 5 is an elevational view of a continuous sorbent polymer composite article that alternates between a first configuration and a second configuration.

[0025] [Figure 6A] FIG. 6A is an elevational view of a sorbent polymer composite article in a first expanded configuration.

[0026] [Figure 6B] FIG. 6B is an elevational view of the sorbent polymer composite article of FIG. 6A in a second, compressed configuration.

[0027] [Figure 6C] FIG. 6C is an elevational view of a sorbent polymer composite article in a first expanded configuration according to another embodiment disclosed herein.

[0028] [Figure 6]FIG. 6D is an elevational view of the sorbent polymer composite article of FIG. 6C in a second, compressed configuration. DETAILED DESCRIPTION OF THE INVENTION

[0029] Detailed Description of the Invention Definitions and Terminology This disclosure is not intended to be interpreted in a limiting sense. For example, the terms used in this application should be read broadly in the context of the meaning that would be ascribed to them by a specialist in the field.

[0030] With respect to the term imprecision, the terms "about" and "approximately" may be used interchangeably to refer to measurements that include the stated measurement and also measurements that are reasonably close to the stated measurement. A measurement that is reasonably close to the stated measurement deviates from the stated measurement by a reasonably small amount, as understood and easily ascertained by one of ordinary skill in the relevant art. Such deviations may result from measurement errors, differences in calibration of measuring and / or manufacturing equipment, human error in reading and / or setting measurements, fine-tuning made to optimize performance and / or structural parameters given differences in measurements associated with other components, specific implementation scenarios, imprecise adjustment and / or manipulation of the object by a human or machine, and the like. If it is determined that the value of such a reasonably small difference would not be easily ascertainable by one of ordinary skill in the relevant art, the terms "about" and "approximately" may be understood to mean plus or minus 10% of the stated value.

[0031] The term "fibril," as used herein, describes an elongated piece of material, such as a polymer, whose length and width differ substantially from one another. For example, a fibril can resemble a string or piece of fiber, whose width (or thickness) is much shorter or less than its length.

[0032] The term "node," as used herein, describes a connection point of at least two fibrils, which may be defined as a location where two fibrils contact each other, either permanently or temporarily. In some instances, a node may also be used to describe a larger volume of polymer than a fibril and where a fibril begins or ends without a clear continuation of the same fibril through the node. In some instances, a node is wider but shorter than a fibril.

[0033] As used herein, "node" and "fibril" may be used to describe objects that are usually, but not necessarily, connected or interconnected and have, for example, microscopic size. A "microscopic" object may be defined as an object that has at least one dimension (width, length, or height) that is so substantially small that the object or details of the object are not visible to the naked eye or are difficult, if not impossible, to observe without the aid of a microscope (such as, but not limited to, a scanning electron microscope (SEM)) or appropriate type of magnifying device.

[0034] Description of Various Embodiments The present disclosure relates to sorbent polymer composite articles, methods for forming sorbent polymer composite articles, and methods for using sorbent polymer composite articles to adsorb and separate one or more desired substances from a source stream. While the sorbent polymer composite articles are described with respect to their use in the DAC of CO from dilute feed streams such as air, they can also be used in other adsorption processes and applications. These processes include, but are not limited to, the adsorption of substances from various inputs, including other gaseous feed streams (e.g., combustion exhaust) and liquid feed streams (e.g., seawater). The adsorbed substance is not limited to CO. Other adsorbed substances may include, but are not limited to, other gas molecules (e.g., N, CH, CO), liquid molecules, solutes, etc. In certain embodiments, the input may be diluted, containing the substance to be adsorbed on the order of parts per million (ppm).

[0035] 2 illustrates a first exemplary sorbent polymer composite article 20 of the present disclosure, including a first composite region 28. The first composite region 28 includes a first porous polymer 22 and a sorbent material 24, 24'. The first composite article 28 can also optionally include a carrier 26. Each element of the first composite region 28 is further described below.

[0036] The first porous polymer 22 of the first composite region 28 can be one of expanded polytetrafluoroethylene (ePTFE), expanded (expanded, expanded, stretched, or foamed) polyethylene (ePE), polytetrafluoroethylene (PTFE), or another suitable porous polymer. It will be understood that nonwoven materials, such as nanospun, meltblown, spunbond, and porous cast films, can be various other suitable porous polymer forms. The first porous polymer 22 can be expanded by stretching the polymer at a controlled temperature and a controlled stretching rate, causing the polymer to fibrillate. After expansion, the first porous polymer 22 can include a microstructure of multiple nodes 30 and multiple fibrils 34 connecting adjacent nodes 30. In these examples, the first porous polymer 22 includes pores 32 bounded by the fibrils 34 and nodes 30. Exemplary node and fibril microstructures are described in U.S. Patent No. 3,953,566 to Gore, which is incorporated herein by reference in its entirety. The pores 32 of the first porous polymer 22 can be considered micropores. Such pores can have a single pore size or can have a distribution of pore sizes. The average pore size can range from 0.1 microns to 100 microns in certain embodiments.

[0037] The sorbent material 24, 24' of the first complex region 28 is a substrate having a surface configured to retain desired substances from the input on the solid surface by adsorption. The sorbent material 24, 24' varies based on which substances are targeted for adsorption. In various embodiments, the sorbent material 24, 24' is a carbon dioxide sorbent material, including, but not limited to, an ion exchange resin (e.g., a strong base anion exchange resin such as Dowex® Marathon® A resin, Dow Chemical available from the Company), zeolites, activated carbon, alumina, metal organic frameworks, polyethyleneimine (PEI), or another suitable carbon dioxide adsorbent material, such as desiccants, carbon molecular sieves, carbon adsorbents, graphite, activated alumina, molecular sieves, aluminophosphates, silicoaluminophosphates, zeolite adsorbents, ion exchanged zeolites, hydrophilic zeolites, hydrophobic zeolites, modified zeolites, natural zeolites, faujasite, clinoptilolite, mordenite, metal exchanged silicoaluminophosphates, monopolar resins, bipolar resins, aromatic crosslinked polystyrene matrices, brominated aromatic matrices, methacrylate ester copolymers, graphite based adsorbents, carbon fibers, carbon nanotubes, nanomaterials, metal salt adsorbents, perchlorates, oxalates, alkaline earth metal particles, ETS, CTS, metal oxides, chemisorbents, amines, organometallic reactants, hydrotalcites, silicalites, zeolitic imadazolate frameworks, and Metal organic frameworks (MOFs), adsorbent compounds, and combinations thereof may be mentioned.

[0038] The sorbent material 24, 24′ can be present in the first porous polymer 22 as a coating, packing, entrained particles, and / or in another suitable form, as described further below. In the embodiment shown in FIG. 2 , the first porous polymer 22 is coated with the sorbent material 24 such that the sorbent material 24 forms a substantially continuous coating on the nodes 30 and / or fibrils 34 of the first porous polymer 22. It is also within the scope of the present disclosure for the first porous polymer 22 to be filled with the sorbent material 24 such that the sorbent material 24 is incorporated into the nodes 30 and / or fibrils 34 of the first porous polymer 22. In the illustrated embodiment of FIG. 2 , particles of the sorbent material 24′ on the carrier 26 are entrained in the first porous polymer 22 such that the sorbent material 24′ occupies the pores 32 between the nodes 30 and / or fibrils 34 of the first porous polymer 22.

[0039] The optional carrier 26 in the first composite region 28 is a material configured to increase the surface area of ​​the region it occupies, thereby increasing the surface area available for adsorption of the desired substance. The carrier 26 can include mesoporous silica, polystyrene beads, porous polymer beds or spheres, oxide supports, or another suitable carrier material. The carrier 26 can further include a porous film containing a porous inorganic material therein, such as calcium sulfate, alumina, activated carbon, or fumed silica. As described above, the carrier 26 can be present within the pores 32 of the first composite region 28 as high-surface-area particles coated or functionalized with a sorbent material 24′. The combination of the carrier 26 coated with a sorbent material 24′ increases the surface area available for adsorption. In these embodiments, the nodes 30 and fibrils 34 may or may not be coated with a sorbent material 24. The original hydrophobicity of the first porous polymer 22 can be maintained when the nodes 30 and fibrils 34 are uncoated.

[0040] The first composite region 28 of the sorbent polymer composite article 20 includes a first side 72 (e.g., the upper side in FIG. 2 ) and a second side 74 (e.g., the lower side in FIG. 2 ). The sorbent polymer composite article 20 further includes a second region 36 including a second porous polymer 40, the second region 36 being disposed adjacent to the first side 72 of the first composite region 28. In various embodiments, the sorbent polymer composite article also includes a third region 38 including a third porous polymer 48, the third region 38 being disposed adjacent to the second side 74 of the first composite region 28. In this manner, the first composite region 28 can be sandwiched between the second region 36 on the first side 72 and the third region on the second side 74. The second porous polymer 40 of the second region 36 can include a plurality of nodes 42, a plurality of fibrils 46 connecting adjacent nodes 42, and a plurality of pores 44 each formed between each node 42 and fibril 46. Similarly, the third porous polymer 48 of the third region 38 may include a plurality of nodes 50, a plurality of fibrils 52 connecting adjacent nodes 50, and a plurality of pores 54 formed between each node 50 and fibril 52. The pores 44 of the second porous polymer 40 and / or the pores 54 of the third porous polymer 48 may be considered micropores, as further described above.

[0041] The first composite region 28, the second region 36, and the third region 38 of the sorbent polymer composite article 20 may be formed using different processes. In certain embodiments, the first composite region 28, the second region 36, and / or the third region 38 may be formed as separate layers and then bonded together. In this case, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and / or the third porous polymer 48 of the third region 38 may be distinct structures. In other embodiments, the first composite region 28, the second region 36, and / or the third region 38 may be formed together and then subjected to different coating processes or surface treatments to distinguish the particular regions, as described further below. In this case, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and / or the third porous polymer 48 of the third region 38 may be continuous or monolithic structures.

[0042] The first composite region 28, the second region 36, and the third region 38 of the sorbent polymer composite article 20 can have different degrees of hydrophobicity. The hydrophobicity can be altered by various methods, such as the application of coatings or surface treatments, including, but not limited to, plasma etching and the application of fine topographical features. The first composite region 28 can have a first hydrophobicity, the second region 36 can have a second hydrophobicity, and the third region 38 can have a third hydrophobicity. The first hydrophobicity is less than the second and third hydrophobicities, respectively. The second hydrophobicity can be less than, greater than, or equal to the third hydrophobicity. The greater hydrophobicity of the second and third regions 36, 38 can reduce the permeability of liquid water through the respective regions 36, 38, thus forming a barrier between the surrounding liquid water and the components of the first composite region 28. This reduces degradation of the sorbent material 24, 24' in the first composite region 28 that can be caused by liquid water, improving the life and durability of the sorbent polymer composite article 20. The increased hydrophobicity of the second region 36 and the increased hydrophobicity of the third region 38 relative to the first hydrophobicity of the first composite region 28 can be attributed to the absence of the sorbent material 24, 24' in the second and third regions 36, 38.

[0043] In some embodiments, the first composite region 28 is sealed with a coating (not shown). In particular examples, the coating is configured to be a carbon adsorbent material similar to the sorbent materials 24, 24' described above.

[0044] The second porous polymer 40 of the second region 36 and the third porous polymer 48 of the third region 38 can be at least one of polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), expanded polyethylene (ePE), or other suitable porous polymers. The second porous polymer 40 of the second region 36 may be the same or different from the third porous polymer 48 of the third region 38. Furthermore, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and the third porous polymer 48 of the third region 38 may be the same or different.

[0045] In various embodiments, the thickness of second region 36 is less than the thickness of first composite region 28, and the thickness of third region 38 is less than the thickness of first composite region 28. The overall thickness of sorbent polymer composite article 20 can be from about 0.1 mm to about 5.0 mm. In certain embodiments, the thickness of first composite region 28 can comprise a majority of the overall thickness, for example, about 70%, about 80%, about 90% or more of the overall thickness.

[0046] The pore characteristics of the porous polymers 22, 40, 48 of the first composite region 28, second region 36, and third region 38, respectively, can be varied. In certain embodiments, the second and third regions 36, 38 can have fewer and / or smaller pores 44, 54 than the first composite region 28 to selectively limit the permeation of undesirable contaminants (e.g., water) into the first composite region 28 while allowing the permeation of desired molecules (e.g., CO) into the first composite region 28. In contrast, the first composite region 28 can have more and / or larger pores 32 than the second and third regions 36, 38 to facilitate the movement of CO through the first composite region 28 for adsorption and desorption.

[0047] Additionally, the pore characteristics can vary between different embodiments, and this variation in pore characteristics can depend on the overall thickness of the sorbent polymer composite article 20, as well as the individual thicknesses of the first composite region 28, the second region 36, and the third region 38.

[0048] FIG. 2A is a schematic elevational view of the first composite region 28 of the sorbent composite article 20 of FIG. 2. In this embodiment, the sorbent polymer composite article 20 (FIG. 2) is relatively thick, e.g., about 3 mm, with the first composite region 28 having a thickness T1 that accounts for a majority of the overall thickness of the sorbent polymer composite 20. The sorbent polymer composite article 20 can be loaded with a desired amount of sorbent material 24 (e.g., about 60% sorbent material 24) to maintain a relatively high porosity, where porosity is the relative ratio of the volume of void space in the first composite region 28 to the overall volume of the first composite region 28. In this manner, the sorbent polymer composite article 20 is structurally relatively open, providing relatively high accessibility to the sorbent material 24. Because of the thickness T1 in this embodiment, the sorbent material 24 remains accessible to gases, although the distance required for gas diffusion may be greater. As a result, the initial rate of gas adsorbing onto the sorbent material 24 may be slower compared to thinner embodiments, as described herein, but equilibrium of CO2 adsorbing onto the sorbent material 24 may be reached more quickly.

[0049] FIG. 2B is an alternative embodiment of the first composite region 28 of FIG. 2A, in which the sorbent composite article 20 (FIG. 2) has a median thickness of, for example, about 0.5 mm. In this embodiment, the first composite region 28 has a thickness T2 that accounts for a majority of the overall thickness of the sorbent polymer composite article 20. In this case, if the amount of polymer 22 (FIG. 2) and the amount of sorbent material 24 in the first composite region are constant compared to the previous embodiment, the porosity is relatively smaller than that of the first composite region 28 of FIG. 2A. Thus, the sorbent polymer composite article 20 maintains a porosity that allows gas access to the sorbent material 24 but is relatively less accessible than the sorbent material 24 of the embodiment of FIG. 2A. As a result, the initial rate of gas adsorption into the sorbent material 24 may be faster due to the shorter diffusion distance, but the time to reach equilibrium CO2 adsorption is increased compared to the embodiment of FIG. 2A.

[0050] FIG. 2C is an alternative embodiment of the first composite region 28 of FIGS. 2A and 2B, in which the sorbent polymer composite article 20 (FIG. 2) is relatively thin, e.g., about 0.1 mm. In this embodiment, the first composite region 28 has a thickness T3 that accounts for a majority of the overall thickness of the sorbent polymer composite article 20. In this case, if the amount of polymer 22 (FIG. 2) and the amount of sorbent material 24 in the first composite region 28 are constant relative to the previous two embodiments, the polymer 22 and available sorbent material 24 are more concentrated within the sorbent polymer composite article 20. The diffusion distance required for gas to pass through the article 20 is shorter due to the compressed thickness of the sorbent polymer composite article 20, but the sorbent material 24 is also less accessible to the gas. As a result, the initial rate of gas adsorption onto the sorbent material 24 is faster than in the previous embodiment, but it may take longer for the system to reach CO2 adsorption equilibrium.

[0051] 2, the pore characteristics of the sorbent polymer composite 20 can vary within each layer, but also across various embodiments as a result of varying various properties including the thickness of the sorbent polymer composite article 20, the thickness of the first composite region 28, the amount of sorbent material 24, 24′ used in the sorbent polymer composite article 20, and the amount of polymer 22. In this manner, the relationship between the diffusion length and the accessibility of the sorbent material 24, 24′ can be varied to maximize the performance of the sorbent polymer composite article 20.

[0052] Additionally, the ability to vary the hydrophobicity, thickness, pore characteristics, and other properties of the first composite region 28, second region 36, and third region 38 can increase the durability and adaptability of the sorbent polymer composite article 20. Additionally, the use of a relatively thin and flexible sorbent polymer composite article 20 may allow the sorbent polymer composite article 20 to conform to different configurations for CO2 adsorption and desorption.

[0053] FIG. 2D is an additional elevational view of the sorbent polymer composite article of FIG. 2 , including an additional edge seal region 21. In certain embodiments, the sorbent polymer composite article 20 includes this edge seal region 21 to protect the components of the sorbent polymer composite article 20. For example, if the sorbent polymer composite article 20 is cut or divided in any manner, such as for production or manufacturing purposes, it may leave the first composite region 28, and thus the sorbent material 24, 24′ within the first composite region 28, exposed to external environmental elements such as water, steam, or debris that may be detrimental to the properties of the sorbent polymer composite article 20. Therefore, an embodiment with an edge seal region 21 may be desirable. As shown in FIG. 2D , the edge seal region 21 can connect the polymer 40 of the second region 36 and the polymer 48 of the third region 38 and is positioned to cover the exposed polymer 28 of the first composite region on at least one side.

[0054] In the illustrated embodiment of FIG. 2D , the edge seal region 21 is formed by applying an additional layer of sealing material 47 onto the sorbent polymer composite article 20. The sealing material 47 may be the same or different from the material of the second region 36 and the third region 36. For example, the sealing material 47 may be ePTFE (as shown in FIG. 2D ), ePE, a silicone elastomer, or any other suitable non-porous and / or hydrophobic material that protects the first composite region 28. In other embodiments, the edge seal region 21 may be formed by extending the second region 36 and the third region 38 and bonding (e.g., sandwiching, gluing) the regions 36, 38 together. The addition of this edge sealing step benefits the composite by protecting the sorbent retained within the composite and strengthening the leading edge of the composite (the area most susceptible to damage from airborne debris and high-velocity impacts).

[0055] FIG. 3 is a flow chart illustrating a method 100 of using the sorbent polymer composite article 20 (FIG. 2) for DAC. The method of using the sorbent polymer composite article 20 (FIG. 2) is described with reference to its use in DAC, but the method can be modified for use in different adsorption processes other than DAC. An example of a first embodiment of this method 100 is shown in FIGS. 4A-4D. Accordingly, method 100 will first be described with reference to FIGS. 3, 4A, 4B, 4C, and 4D. Next, in the following paragraphs, method 100 will be described with reference to FIG. 5 and FIGS. 6A-6D.

[0056] At block 102, the method 100 first includes providing a sorbent polymer composite article 20 having a porous composite portion 62. In certain embodiments, the porous composite portion 62 includes a first composite layer 28, a second layer 36, and a third layer 38 having an adsorbent material 24, 24′ and a first porous polymer 22, as shown and described above with respect to FIG. 2. In certain examples, block 102 can further include providing a non-porous portion 64 coupled to the porous composite portion 62 of the sorbent polymer composite article 20. In the embodiment of FIGS. 4A and 4C, the non-porous portion 64 is located at an outermost end 68 of the porous composite portion 62 of the sorbent polymer composite article 20. The length of the porous composite portion 62, the non-porous portion 64, and / or the overall length of the sorbent polymer composite article 20 can vary.

[0057] At block 104, the method 100 includes exposing the sorbent polymer composite article 20 in a first adsorption configuration to a feed stream 60. The sorbent polymer composite article 20 can have a substantially layered morphology in the first configuration such that the porous portions 62 are exposed to the feed stream 60 without being obscured by the non-porous portions 64, examples of which are shown in FIGS. 4A and 4C. In this first configuration, the sorbent polymer composite article 20 can be held by a support structure 70. The flexible nature of the sorbent polymer composite article 20 can allow the sorbent polymer composite article 20 to extend outward from the support structure 70 like a fabric flag or banner. While a horizontal configuration is described in the exemplary embodiment of FIGS. 4A-4D, additional vertical configurations are contemplated. In some examples, the sorbent polymer composite can be supported by structures 70 at each end of the sorbent polymer composite article 20, with the material traversing between the supports 70. In various embodiments, the feed stream 60 includes at least CO2 and one other substance. Feed stream 60 can be similar to the feed stream of input 11 shown and described with reference to Figure 1. Feed stream 60 can be directed in a substantially parallel direction, a substantially perpendicular direction, or another suitable direction across sorbent polymer composite article 20, as shown in Figures 4A and 4C.

[0058] At block 106, the method 100 includes adsorbing CO onto the sorbent material 24, 24' (FIG. 2) of the sorbent polymer composite article 20 while the sorbent polymer composite article 20 is in the first configuration. In various embodiments, at least a portion of the CO in the feed stream 60 is adsorbed onto the sorbent material 24, 24' (FIG. 2) of the porous portion 62 of the sorbent polymer composite article 20. In certain examples, the sorbent polymer composite article 20 is maintained in the first configuration until its CO adsorption capacity is reached. This occurs when the amount of CO adsorbed onto the sorbent material 24, 24' of the sorbent polymer composite article 20 equals the maximum amount of CO that the sorbent material 24, 24' of the sorbent polymer composite article 20 can adsorb. It is also within the scope of the present disclosure to discontinue the adsorption step of block 106 before the sorbent polymer composite article 20 reaches its adsorption capacity. For example, the dynamics of the system may be limited so that the amount of CO2 adsorbed onto the sorbent material 24, 24' reaches equilibrium and plateau before reaching adsorption capacity. In this example, the adsorption step of block 106 may be stopped when the amount of CO2 adsorbed onto the sorbent material 24, 24' plateaus.

[0059] In block 108, the method 100 includes placing the sorbent polymer composite article 20 in a second desorption configuration after adsorbing CO2 onto the sorbent polymer composite article 20 in the previous block 106. In certain examples, this placing step in block 108 occurs after or before reaching adsorption capacity. In the second configuration, the sorbent polymer composite article 20 can have a substantially rolled or wound cylindrical shape, with the porous portion 62 rolled onto the porous drum 72 and the non-porous portion 64 rolled onto the porous portion 62. Thus, according to some examples, the inner porous portion 62 can be concealed by the outer non-porous portion 64. The non-porous portion can apply a vacuum within the porous drum 72. Applying a vacuum or negative pressure is a standard method for extracting desorbed CO2. In some examples, the porous portion 62 can be temporarily covered by the outer non-porous portion 64, which can include one or more layers of non-porous material. In some instances, the porous portion 62 may be physically separated, insulated, or protected from the external environment by an outer non-porous portion 64 .

[0060] In block 110, the method 100 includes desorbing CO2 while the sorbent polymer composite article 20 is in the second configuration by exposing the sorbent polymer composite article 20 to a desorption source 80 (e.g., water, water vapor, and / or heat). In the embodiment shown in Figures 4B and 4D, this desorption step in block 110 includes injecting water vapor as the desorption source 80 longitudinally through the center of the sorbent polymer composite article 20 while it is in the second configuration. The edge seal region 21 (Figure 2) can protect the sorbent material 24, 24'. Because the material is confined to a much smaller shape during the desorption step, the energy required for desorption can be minimized compared to conventional systems. The sorbent polymer composite article 20 has a degree of flexibility that facilitates transformation between the first and second configurations without the need for hinges and additional components. This desorption step in block 110 can vary depending on alternating geographic regions, seasons, temperatures, and climates.

[0061] The formation of water droplets can inhibit both adsorption from the feed stream 60 during the adsorption step of block 106 and the desorption of CO2 that occurs during the desorption step of block 110. The feed stream 60 can contain enough water vapor to form droplets on the sorbent polymer composite article 20 that inhibit CO2 adsorption. Similarly, droplets can condense on the sorbent polymer composite article 20 during desorption. In such situations, the droplets can be removed from the sorbent polymer composite article 20 by shaking, vibrating, rocking, or otherwise moving the sorbent polymer composite article 20. These techniques can improve adsorption and desorption efficiencies, respectively. This mobility represents an additional benefit of the flexibility of the sorbent polymer composite article 20. Various means of imparting motion to remove droplets are known to those skilled in the art and can include physically vibrating the sorbent polymer composite article 20, shaking the structure 70, applying pulsed air, and / or vibrating the structure 70 with sound or magnetic forms. This step of shaking or vibrating the sorbent polymer composite article 20 can occur simultaneously with, before, and / or after the exposing step of block 104, the adsorbing step of block 106, the disposing step of block 108, and the desorbing step 110 of block 108.

[0062] In certain examples, the method 100 further includes recovering the extracted CO. This recovery process can be performed using a vacuum to recover the liberated CO.

[0063] Another embodiment of the method 100 of Figure 3 involves the use of a sorbent polymer composite article 20' shown in Figure 5. The sorbent polymer composite article 20' can be similar to the sorbent polymer composite article 20 described above, except as described below, and like reference numbers identify like elements.

[0064] In the embodiment shown in FIG. 5, the providing step of block 102 (FIG. 3) includes disposing a belt-like porous composite portion 62 along a continuous path 81 having a first portion 82 (e.g., upper portion in FIG. 5) and a second portion 84 (e.g., lower portion in FIG. 5). The exposing step of block 104 (FIG. 3), in which the sorbent polymer composite article 20′ is in a first configuration, includes disposing at least a portion of the porous composite 62 in the first (e.g., upper) portion 82 of the path 81 in communication with the feed stream 60. The adsorption step of block 106 (FIG. 3) includes adsorbing CO2 from the feed stream 60 onto the portion of the sorbent polymer composite article 20′ disposed in the first configuration. The disposing step of block 108 (FIG. 3), in which the sorbent polymer composite article 20′ is in a second configuration, includes disposing at least a portion of the porous composite 62 in the second (e.g., lower) portion 84 of the path 81 in communication with the desorption source 80. The desorption step of block 110 (FIG. 3) involves exposing the portion of the sorbent polymer composite article 20′ arranged in the second configuration to a desorption source 80 to desorb CO. In the embodiment shown in FIG. 5, this desorption source 80 is water vapor (e.g., a greenhouse containing water vapor). In the greenhouse example, the released CO can be used by plants. In certain other embodiments, the extracted CO can be recovered after the desorption step of block 110.

[0065] As shown in FIG. 5 , the sorbent polymer composite article 20′ is supported by rollers 86a, 86b, 86c, and 86d and can be continuously rotated along a path 81. In this embodiment, the sorbent polymer composite article 20′ operates as an endless track, continuously rotating between a first configuration when positioned in a first portion 82 of the path 81 and a second configuration when positioned in a second portion 84 of the path 81. In this manner, each point along the length of the sorbent polymer composite article 20′ can experience adsorption in the first configuration, desorption and regeneration when rotated to the second configuration, further adsorption when rotated back to the first configuration, and so on. The flexibility of the sorbent composite article 20 facilitates the transition between the first and second configurations without the need for additional components, including, but not limited to, hinge components. This embodiment also allows for simultaneous adsorption and desorption with a single sorbent polymer composite article 20′. For example, adsorption can occur in the top half of the sorbent polymer composite article 20' arranged in a first configuration, while desorption can occur simultaneously in the bottom half of the sorbent polymer composite article 20' arranged in a second configuration. The rate at which the sorbent polymer composite 20' moves can be varied according to its adsorption and desorption capacity or based on its kinetics as it reaches equilibrium.

[0066] Another embodiment of the method 100 of FIG. 3 involves the use of a sorbent polymer composite article 20'', examples of which are shown in FIGS. 6A-6D. The sorbent polymer composite article 20'' can be similar to the sorbent polymer composite article 20 described above, except as described below, and like reference numbers identify like elements.

[0067] In this embodiment, the first configuration, corresponding to the exposing step of block 104 (FIG. 3), is an expanded or unfolded configuration, examples of which are shown in FIGS. 6A and 6C. The second configuration, corresponding to the deploying step of block 108 (FIG. 3), is a compressed or folded configuration, examples of which are shown in FIGS. 6B and 6D. The sorbent polymer composite article 20'' can be a lattice structure having hinge points 91 to accommodate such unfolding and folding. In this embodiment, the height 90 of the sorbent polymer composite article 20'' in the first, expanded configuration is greater than the height 92 of the sorbent polymer composite article 20'' in the second, compressed configuration.

[0068] In certain embodiments, the sorbent polymer composite article 20" can include regions that include the sorbent material 24 (e.g., filled regions) and regions that do not include the sorbent material 24 (e.g., unfilled regions). The regions that do not include the sorbent material 24 can be more conformal than the regions that include the sorbent material 24. This ability to control the conformability of the sorbent polymer composite article 20" can also make it possible to control the location of the hinge point 91. To increase durability, a substance such as silicone may be associated with the regions of the sorbent polymer composite article 20 that do not include the sorbent material 24. The flexibility of the sorbent composite article 20 facilitates conversion between a first configuration and a second configuration without the need for mechanical hinges and additional components that increase cost and reduce lifespan and durability.

[0069] Additionally, the desorption step of block 110 (FIG. 3) can include exposing the sorbent polymer composite article 20" to a desorption source 80. In the embodiment shown in FIGS. 6B and 6D, the desorption source 80 can be water, whereby the desorption step involves immersing the sorbent polymer composite article 20" in water while in the second, compressed configuration to desorb the CO2. In other embodiments, the desorption source 80 can be steam or heat. Those skilled in the art will clearly recognize the potential for energy savings by minimizing the volume occupied by the sorbent polymer composite during the desorption step. This reduction in volume results in reduced energy usage and ultimately reduced costs.

[0070] An additional benefit of flexible sorbent polymer composites is their ability to be reduced in volume (e.g., folded, rolled, or wound). Minimizing the volume of an air contactor or module can reduce storage space at a CO2 capture site, inventory space at a manufacturing site, and transportation and packaging costs. These benefits are listed but are not intended to be limiting. To further illustrate, the benefits of volume reduction can be far-reaching, including reducing the number of workers required to replace a sorbent polymer composite of the present invention. For example, while in a deployed or adsorbing configuration, a sorbent polymer composite is bulky and requires a team of technicians to handle and replace it, whereas a folded or spooled sorbent polymer composite of the present invention can require only one technician to perform the same task that previously required multiple technicians.

[0071] Various modifications and additions can be made to the exemplary embodiments described without departing from the scope of the present disclosure. For example, while the above-described embodiments refer to particular features, the scope of the present disclosure also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present disclosure is intended to encompass all alternatives, modifications, and variations falling within the scope of the claims, together with all equivalents thereof.

Claims

1. 1. A sorbent polymer composite article comprising a flexible composite of a sorbent and a flexible porous polymer, said sorbent polymer composite article comprising: an adsorption configuration in which the sorbent polymer composite article is arranged to adsorb one or more components of a feed stream; a desorption configuration in which said sorbent polymer composite article is configured to remove one or more components from said sorbent polymer composite article; and A sorbent polymer composite article, wherein the flexibility of said flexible porous polymer facilitates transformation between said adsorbing configuration and said desorbing configuration.

2. The sorbent polymer composite article of claim 1 , wherein said sorbent polymer composite article further comprises a carrier.

3. The sorbent polymer composite article of claim 1 , wherein the feed stream comprises carbon dioxide.

4. The sorptive polymer composite article of claim 1 , wherein said sorptive polymer composite article is substantially laminar in said adsorption configuration and substantially cylindrical in said desorption configuration.

5. The sorbent polymer composite article comprises: an expanded arrangement in an adsorption configuration; and a compressed arrangement in the detached configuration; The sorbent polymer composite article of claim 1 , comprising:

6. The sorbent polymer composite article of claim 1 , wherein said sorbent polymer composite article is substantially unfolded in said adsorbing configuration and substantially folded in said desorbing configuration.

7. The sorbent polymer composite article of claim 1 further comprising a non-porous portion that does not contain said sorbent, said non-porous portion being bonded to said composite.

8. The sorbent polymer composite article of claim 7 , wherein said non-porous portion is bonded to an outermost edge of said composite.

9. The sorbent polymer composite article of claim 7 , wherein the porous polymer of the composite is temporarily covered by the non-porous portion when the sorbent polymer composite article is in the detached configuration.

10. The sorptive polymer composite article of claim 1 , wherein said sorptive polymer composite article transitions from said adsorbing configuration to said desorbing configuration upon reaching the adsorption capacity or adsorption equilibrium of said sorptive polymer composite article.

11. The sorbent polymer composite article of claim 1 , wherein the sorbent polymer composite article returns from the desorbing configuration to the adsorbing configuration.

12. 1. A method of using a sorbent polymer composite article, comprising: providing a sorbent polymer composite article comprising a porous composite portion comprising a sorbent and a flexible porous polymer; exposing the sorbent polymer composite article in a first configuration to a feed stream comprising carbon dioxide; adsorbing at least a portion of the carbon dioxide onto the sorbent while the sorbent polymer composite article is in the first configuration; placing the sorbent polymer composite article in a second configuration after the adsorbing step; and desorbing carbon dioxide from said sorbent polymer composite article while said sorbent polymer composite article is in said second configuration; A method comprising the steps of:

13. 13. The method of claim 12, further comprising maintaining the sorbent polymer composite article in the first configuration until the sorbent reaches carbon dioxide capacity or equilibrium, and wherein the placing step occurs once the carbon dioxide capacity or equilibrium is reached.

14. the providing step further comprises bonding a non-porous portion having a flexible polymer to the flexible porous polymer of the porous composite portion; the exposing step further comprises disposing the sorbent polymer composite article in a substantially layered configuration; and The method of claim 12 , wherein the placing step further comprises placing the sorbent polymer composite article in a substantially cylindrical shape, the porous composite portion being obscured by the non-porous portion.

15. 15. The method of claim 14, wherein the desorbing step comprises injecting water vapor into the center of the sorbent polymer composite article in the second configuration and recovering at least a portion of the carbon dioxide.

16. The method of claim 12 , further comprising returning the sorbent polymer composite article from the second configuration to the first configuration after the desorbing step.

17. further comprising alternating the sorbent polymer composite article along a path having a first portion and a second portion; during an exposure step with the sorbent polymer composite article in the first configuration, a portion of the sorbent polymer composite article is positioned in the first portion of the path; and The method of claim 12 , wherein during the placing step with the sorbent polymer composite article in the second configuration, a portion of the sorbent polymer composite article is placed in the second portion of the pathway.

18. 20. The method of claim 17, wherein said alternating step reduces the volume occupied by said sorbent polymer composite article.

19. The method of claim 17 , wherein the desorbing step further comprises immersing the porous composite portion in the second configuration in a substance to desorb carbon dioxide.

20. 20. The method of claim 19, wherein the substance is water or water vapor.

21. 13. The method of claim 12, further comprising recovering the extracted carbon dioxide after the desorbing step.

22. 18. The method of claim 17, wherein said alternating step is performed continuously such that said sorbent polymer composite article continuously transitions between said first configuration and said second configuration.

23. the exposing step includes placing the sorbent polymer composite article in an expanded configuration; and The method of claim 12 , wherein the placing step comprises placing the sorbent polymer composite article in a compressed configuration.

24. 24. The method of claim 23, wherein the height of the sorbent polymer composite article in the expanded configuration is greater than the height of the sorbent polymer composite article in the compressed configuration.

25. 24. The method of claim 23, wherein the desorbing step further comprises immersing the sorbent polymer composite article in the second configuration in a material that desorbs carbon dioxide.

26. The method of claim 12 , wherein the sorbent polymer composite article further comprises an edge seal region that protects the sorbent.

27. The method of claim 12 further comprising moving the sorbent polymer composite article to substantially remove the droplets.

28. The method of claim 12 , wherein the feed stream further comprises steam or heat.

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