Self-assembled carbon dioxide removal structure and method of manufacturing the same

Abstract

The present invention relates to a self-assembled carbon dioxide removal structure, in particular a carbon dioxide removal structure useful for direct air carbon capture (DAC), and methods of its manufacture and regeneration. The carbon dioxide removal structure comprises a support having at least one attachment surface with a negative triboelectric surface charge density of less than -150 µC m ‑2 ; and a plurality of amine-containing sorbent particles capable of adsorbing or binding carbon dioxide and self-assembling on the support.

Description

Technical Field

[0001] This invention relates to self-assembled carbon dioxide removal structures, particularly carbon dioxide removal structures that can be used for direct air carbon capture (DAC), and methods for manufacturing and regenerating them. Background Technology

[0002] Carbon capture is a process designed to capture carbon dioxide (CO2) emissions from industrial processes, particularly those related to the combustion of fossil fuels. The primary objective is often to mitigate the climate change impacts of CO2, a major greenhouse gas. In a carbon capture system, CO2 is separated from other gases emitted during combustion or industrial activities before being released into the atmosphere.

[0003] Direct air carbon capture (DAC) is a technology designed to remove carbon dioxide (CO2) directly from ambient air, regardless of its source. Unlike traditional carbon capture technologies that capture CO2 emissions from specific point sources such as power plants, DAC focuses on extracting CO2 directly from the atmosphere. The captured CO2 can be stored underground, used in various industrial processes, or converted into valuable products.

[0004] Monolithic and packed-bed adsorber structures are commonly used in carbon capture technologies, particularly in adsorption-based processes where gases such as carbon dioxide (CO2) are captured by the medium. Both structures provide a large surface area for effective contact between the CO2-containing gas and the capture medium. Laminated sheet or plate systems can also be used, thus providing aspects of each of the aforementioned systems. WO2021239747A1 describes a laminated sheet or plate system for DAC (Carbon Capture Demand).

[0005] A monolithic structure is a structured and continuous adsorbent support system designed to facilitate efficient chemical reactions. It typically consists of a single solid component with a highly porous structure, providing a large surface area for adsorption. Key characteristics of monolithic structures are:

[0006] Structured design: The monolithic structure is designed with a specific geometry, typically resembling a honeycomb or a series of parallel channels. This structured design ensures uniform flow distribution and minimizes contact between reactants and adsorbents.

[0007] Porosity: The monolithic structure is characterized by high porosity. The walls of the channels or honeycomb structure are filled with adsorbent material. This porous structure allows gas molecules to flow through the channels and approach the adsorbent.

[0008] Adsorbent immobilization: Adsorbent materials are typically immobilized within a porous structure of a monolithic design. Various techniques, such as impregnation, deposition, or coating, are used to ensure uniform distribution and immobilization of the adsorbent material throughout the monolithic structure.

[0009] Packed beds for adsorption are structured arrangements of adsorbent material, typically in the form of spheres or extrusions, within a container. Proper design and control of the flow and regeneration processes are crucial for efficient adsorption and regeneration.

[0010] A layered sheet or plate system consists of multiple air-collecting surfaces, each comprising parallel-arranged solid sheets or plates to provide fluid flow channels therebetween. These channels can serve as both airflow and heating fluid flow channels, and can be arranged such that heating channels are located on either side of the airflow channels.

[0011] Monolithic structures, layered sheet systems, and filled beds each have their own advantages and disadvantages.

[0012] Monolithic structures and layered sheet systems offer the following advantages:

[0013] (1) Low pressure drop: Compared to packed beds, monolithic structures and layered sheet systems typically offer lower pressure drop. This means that fluid can flow through monolithic structures or layered sheet systems with less resistance, which is crucial in applications where maintaining a specific flow rate or minimizing energy consumption is important.

[0014] (2) High surface area: Monolithic structures and layered sheet systems typically have a high surface area per unit volume, making them well-suited for processes involving surface interactions, such as catalysis and adsorption. The increased surface area can lead to higher efficiency in these processes.

[0015] (3) Uniform flow distribution: Monolithic and layered sheet systems are designed to provide a uniform flow distribution across their entire surface. In contrast, packed beds may suffer from channeling or non-uniform flow, which can lead to non-uniform contact between the fluid and the solid phase.

[0016] (4) Increased quality transfer: The structured design of monolithic structures and layered sheet systems can promote efficient quality transfer.

[0017] (5) Anti-clogging: Monolithic structures and layered sheet systems are generally less susceptible to particle blockage or clogging, which can be a problem in packed beds when fine particles or contaminants are present in the fluid.

[0018] (6) Easy to scale up: Monolithic structures and layered sheet systems can be more easily scaled up in size and adapted to different applications. They can be manufactured in various shapes (especially monolithic structures) and sizes to meet specific process requirements.

[0019] (7) Improved heat transfer: Due to their high surface area and uniform flow distribution, monolithic structures and layered sheet systems can promote efficient heat transfer. This makes them suitable for applications involving heat exchange and temperature control.

[0020] (8) Reduced material usage: Compared to packed beds, monolithic and layered sheet systems can be designed with thinner walls and less material, making them a more resource-efficient option.

[0021] (9) Easy to clean and maintain: Cleaning and maintaining a monolithic structure may be simpler than that of a filled bed, especially when dealing with fouling or contamination issues.

[0022] The packed bed offers the following advantages:

[0023] (1) Versatility: The packed bed can accommodate various particle sizes and shapes, thus allowing for flexible selection of filling materials to meet specific process requirements.

[0024] (2) Scalability: Packed beds are generally easier to scale up for large industrial processes. They can be sized to fit a variety of production scales without major design changes.

[0025] (3) Simple construction and easy replacement: The construction and replacement of the filling bed are relatively simple, which makes them cost-effective and convenient in the process of needing frequent replacement or maintenance.

[0026] (4) Mixing and redistribution: When needed, packed beds can provide better mixing of reactants or fluids. In some cases, the random arrangement of particles in a packed bed can enhance mass transfer and chemical reactions.

[0027] (5) High porosity option: Packed beds can be designed with high porosity, allowing gas or liquid to permeate effectively through the bed, which is advantageous in some applications.

[0028] (6) Cost-effective materials: The filling materials used for the filling bed are usually readily available and cost-effective compared to the manufacture of complex monolithic structures.

[0029] (7) Anti-clogging ability: In some cases, packed beds may have better anti-clogging or clogging ability because the particles can be replaced or cleaned more easily compared to monolithic structures with complex channels.

[0030] (8) Adaptability to non-uniform flow: When the flow rate is non-uniform or the flow pattern needs to be adjusted, the packed bed can be manipulated more easily to achieve the desired flow distribution.

[0031] (9) Established design guidelines: Filled beds have been widely used for decades, providing engineers and operators with comprehensive design guidelines and a wealth of practical knowledge.

[0032] The choice between packed beds, layered plate or sheet systems, and monolithic structures typically depends on the specific requirements of the process, including factors such as reaction or separation type, fluid properties, space constraints, and economic considerations. Each structure has its unique advantages and is usually selected based on the requirements of a given application. However, designing adsorbers for direct air capture (DAC) (a technology for the direct removal of carbon dioxide (CO2) from the atmosphere) faces several challenges, including:

[0033] (1) Low CO2 concentration: The ambient air contains only trace amounts of CO2 (about 0.04%), making it a dilution source. The adsorber must be highly selective to efficiently capture CO2 while minimizing the adsorption of other gases such as nitrogen and oxygen.

[0034] (2) Energy requirements: DAC involves adsorbing CO2 from a large amount of air, and releasing the captured CO2 requires a large amount of energy, usually in the form of heat. Designing energy-efficient adsors and optimizing energy is a critical challenge.

[0035] (a) Adsorption: Due to the dilutive nature of CO2 in the atmosphere, large volumes of air need to be processed, which typically involves passing large volumes of air through an adsorber. Generally, for adsorption-based gas separation processes, the required adsorbent material configuration imposes a small pressure drop on the gas flow to minimize the energy required for gas pumping, while simultaneously maximizing contact between the adsorbent and the gas flow to maximize the mass transfer rate of components removed from the gas flow. Typical configurations include packed bed columns or fluidized beds, typically ranging from tens of centimeters to several meters in length, which typically impose a pressure drop of several thousand Pascals to several bar on the gas flow. This can generate large pressure drops on the adsorbent bed, thus increasing energy consumption. Therefore, thin adsorbent beds or monolithic systems are preferred.

[0036] (b) Regeneration: Regenerating the adsorbent to release captured CO2 involves heating and energy consumption. Achieving an efficient and economical regeneration process while minimizing heat loss is a challenge. Effective thermal management is crucial for reducing energy consumption. Integrating heat recovery systems and optimizing heat exchange between different process flows are complex tasks.

[0037] (3) Adsorbent stability: Selecting the right adsorbent is crucial. The adsorbent must have high CO2 adsorption capacity, good selectivity, and the ability to withstand cyclic adsorption-desorption processes without degradation. DAC systems are designed for long-term operation. The adsorbent must be stable and durable, minimizing degradation over time due to cyclic loading and regeneration.

[0038] (4) Adsorption kinetics: Achieving rapid CO2 adsorption and desorption kinetics is crucial for efficient DACs. Designing an adsorber that promotes rapid CO2 mass transfer while maintaining high capacity is a challenge.

[0039] (5) Pollutant Management: Ambient air contains various impurities, including dust and volatile organic compounds. These pollutants can contaminate or poison the adsorbent, requiring effective pretreatment and filtration systems to protect it.

[0040] Overcoming these challenges will help in the development and implementation of effective DAC systems that can mitigate climate change by removing CO2 from the atmosphere.

[0041] The present invention aims to eliminate or mitigate one or more challenges associated with the prior art, or to provide an alternative adsorbent structure that can be used for carbon capture, particularly direct air carbon capture.

[0042] It would be useful to provide an adsorber structure that can be used for direct air capture of carbon dioxide.

[0043] It would be useful to provide an adsorber structure that is relatively easy to manufacture and / or cost-effective.

[0044] It would be useful to provide an adsorbent structure that is easy to replace when the adsorbent degrades or becomes deactivated.

[0045] It would be useful to provide an adsorbent structure that allows for rapid heat transfer to / from the adsorbent. Summary of the Invention

[0046] According to the present invention, a carbon dioxide removal structure for separating gaseous carbon dioxide from a gas mixture containing gaseous carbon dioxide is provided, comprising:

[0047] A support having at least one attachment surface, wherein the negative vacuum triboelectric surface charge density of the attachment surface is less than -150 µc m -2 ;

[0048] Multiple amine-containing adsorbent particles, which can adsorb or bind carbon dioxide;

[0049] Multiple amine-containing adsorbent particles self-assemble on at least one attachment surface of the support.

[0050] The ability to rapidly transfer heat to and from the adsorbent is a key feature of this invention. It allows for rapid regeneration of the adsorbent (i.e., removal of CO2 from the adsorbent) because the organized, self-assembled layers of adsorbent particles, particularly when attached to the support surface, allow for highly efficient heat transfer, significantly reducing the total cycle time and thus increasing adsorbent productivity. This contrasts with conventional packed beds, where heat transfer is primarily through particle-to-particle conduction, resulting in slow heat transfer and consequently long regeneration times.

[0051] The negative vacuum triboelectric surface charge density was measured according to the method described in the following literature: Lui et al. Standardized measurement of dielectric materials' intrinsic triboelectric charge density through the suppression of air breakdown. Nature Communications. (2022) Oct;13(1):6019. DOI: 10.1038 / s41467-022-33766-z. PMID:36224185; PMCID: PMC9556570., the full text of which, together with its publicly available supplemental information, is incorporated herein by reference.

[0052] Preferably, the negative vacuum triboelectric surface charge density of the adhesion surface is less than -200 µc m. -2 .

[0053] Preferably, the negative vacuum triboelectric surface charge density of the adhesion surface is less than -250 µc m. -2 .

[0054] Preferably, the negative vacuum triboelectric surface charge density is measured in a vacuum.

[0055] Preferably, the negative vacuum triboelectric surface charge density is approximately 5 × 10⁻⁶. -5 Measured at a vacuum pressure of Pa or lower.

[0056] Preferably, the negative vacuum triboelectric surface charge density is measured at a temperature of 400 Kelvin (400 K) or lower.

[0057] Under vacuum conditions (here, vacuum is approximately 5 × 10⁻⁶) -5Induced charge density σ under vacuum pressure of Pa or greater I It is independent of the thickness t of the material being measured. Under high vacuum conditions (approximately 5 × 10⁻⁶), -5 Under Pa), σ I As the temperature rises to 400K, it remains almost stable.

[0058] Optionally, an iron (Fe) electrode is used in the measurement of the charge density of a negative vacuum triboelectric surface.

[0059] A carbon dioxide removal structure for separating gaseous carbon dioxide from a gas mixture containing gaseous carbon dioxide, comprising:

[0060] A support having at least one attachment surface, the attachment surface being a material selected from the group consisting of:

[0061] Halogenated polymers;

[0062] Polyimide;

[0063] Polysulfone;

[0064] Polystyrene;

[0065] Silicone rubber;

[0066] Quartz glass;

[0067] Acetylcellulose tablets;

[0068] Polyethylene; and

[0069] Multiple amine-containing adsorbent particles, which can adsorb or bind carbon dioxide;

[0070] Multiple amine-containing adsorbent particles self-assemble on at least one attachment surface of the support.

[0071] Preferably, the gas mixture containing the gaseous carbon dioxide is ambient air.

[0072] Alternatively, the support is a porous solid substrate.

[0073] Alternatively, the support is a non-porous solid substrate.

[0074] Alternatively, the support structure can be a monolithic structure.

[0075] Optionally, at least some of the inner surfaces of the porous solid substrate or monolithic structure include at least one attachment surface.

[0076] Optionally, the support may comprise one or more layered plates or sheets.

[0077] This can be referred to as a layered or laminated system, or a sheet or plate system.

[0078] Advantageously, the layered sheets or plates are arranged to form channels through which fluid can flow. Preferably, the channels are multiple substantially parallel channels. The channels may be elongated in two dimensions.

[0079] Preferably, the channels are interleaved to form air channels and separate heating fluid channels using alternating channels.

[0080] Optionally, a secondary support structure is provided on the side of the amine-containing adsorbent particles opposite to the adhesion surface.

[0081] Optionally, when the support comprises one or more layered plates or sheets, the secondary support structure is configured as a mesh structure. The mesh structure can be in the form of a cage that is substantially the same shape as the channel.

[0082] Optionally, the attachment surface is formed by a coating on the surface of the support.

[0083] Alternatively, the attachment surface is formed by and integrally formed with the support itself.

[0084] Optionally, at least the surface to which the material is attached contains a halogenated polymer or a halogenated polymer.

[0085] Optionally, at least the surface to which the material is applied contains a fluorinated polymer or a fluorinated polymer.

[0086] Optionally, the attachment surface comprises a material selected from the group consisting of:

[0087] Polyvinyl chloride (PVC);

[0088] Polytetrafluoroethylene (PTFE);

[0089] Polypropylene;

[0090] Acrylonitrile butadiene styrene;

[0091] Polyphenylene sulfide;

[0092] Acetaldehyde;

[0093] Polyethylene;

[0094] Cellulose acetate tablets;

[0095] Quartz glass;

[0096] Polydichloroethylene;

[0097] Polyvinylidene fluoride;

[0098] Silicone rubber;

[0099] Fluorinated ethylene propylene (FEP);

[0100] Polystyrene;

[0101] Polysulfone;

[0102] Fluororubber;

[0103] Polyimide;

[0104] Polyetheretherketone;

[0105] Polytetrafluoroethylene;

[0106] Polyvinyl chloride;

[0107] Perfluoroalkoxy (PFA).

[0108] In a preferred embodiment, the attachment surface is polyvinyl chloride (PVC).

[0109] In another preferred embodiment, the attachment surface is polytetrafluoroethylene (PTFE).

[0110] Advantageously, PTFE exhibits wide temperature stability and is highly corrosion resistant. This is beneficial because the carbonic acid produced by high concentrations of CO2 dissolved in water at high temperatures can corrode typical structural materials such as stainless steel and aluminum.

[0111] In another preferred embodiment, the adhesion surface is silicone rubber.

[0112] In another preferred embodiment, the attachment surface is fluorinated ethylene propylene (FEP).

[0113] In another preferred embodiment, the attachment surface is perfluoroalkoxy (PFA).

[0114] Alternatively, the support itself is a halogenated polymer.

[0115] In a preferred embodiment, the support itself is polyvinyl chloride (PVC).

[0116] In another preferred embodiment, the support itself is polytetrafluoroethylene (PTFE).

[0117] In another preferred embodiment, the support itself is silicone rubber.

[0118] Optionally, the amine-containing adsorbent particles contain commercial anion exchange resins.

[0119] Alternatively, the amine-containing adsorbent particles may contain a metal-organic framework (MOF).

[0120] Preferably, the amine-containing adsorbent particles are uniformly distributed on at least one attachment surface of the support.

[0121] Preferably, the amine-containing adsorbent particles are not mixed or combined with a separate chemical binder. Preferably, no chemical binder is present (or only in trace amounts that do not have significant binding activity between the amine-containing adsorbent particles and the attachment surfaces of the support).

[0122] Adhesives are an additional cost in manufacturing monolithic structures. Besides binding the active material (adsorbent) to the monolithic structural walls, they generally lack active function in carbon capture. They can clog activated carbon capture sites, thus impairing adsorbent performance. They must withstand temperature cycling, which causes thermal expansion / contraction of the underlying monolithic structure, leading to detachment of the coating / active layer from the monolithic structure. Furthermore, typical amine adsorbents expand and contract with the adsorption and desorption of CO2 and water vapor, further limiting the role of adhesives. In this invention, the absence of adhesives eliminates or reduces the detrimental effects of expansion / contraction associated with adsorption / desorption and temperature cycling. It also eliminates or reduces the detrimental effects of adhesives on pore / active site clogging.

[0123] Optionally, the support includes one or more tubes, wherein the interior of the tubes is an attachment surface.

[0124] Optionally, the support includes an integral structure comprising multiple internal channels having one or more attachment surfaces. Optionally, the integral structure includes multiple parallel channels. Optionally, the integral structure includes a honeycomb structure.

[0125] Optionally, the support comprises one or more layered plates or sheets, wherein the surface of the plate or sheet is the attachment surface.

[0126] A method for manufacturing the carbon dioxide removal structure described above, comprising:

[0127] A slurry is injected into a support having one or more attachment surfaces. The slurry contains multiple amine-containing adsorbent particles and an aqueous fluid. The adsorbent particles are capable of adsorbing or binding carbon dioxide.

[0128] The slurry present on one or more adhesion surfaces is dried to remove most of the aqueous fluid;

[0129] This allows amine-containing adsorbent particles to assemble on one or more attachment surfaces.

[0130] Advantageously, adsorbent particles are assembled on one or more attachment surfaces and uniformly coated on these surfaces. The adsorbent particles adhere to the attachment surfaces without the need for an adhesive. In this way, the adsorbent particles are releasably bound to the attachment surfaces without the need for an adhesive (which can be released by rinsing with an aqueous substance, such as water).

[0131] Preferably, the method further includes the step of filtering an aqueous fluid from the adsorbent particles.

[0132] Preferably, the step of filtering the aqueous fluid from the adsorbent particles is performed before or simultaneously with the drying step.

[0133] Preferably, the drying step is carried out at an elevated temperature.

[0134] Optionally, the drying step may be carried out at 80 degrees Celsius (80°C).

[0135] Optionally, the drying step may be carried out at 70 to 90 degrees Celsius (70-90°C).

[0136] Preferably, any excess aqueous fluid is drained from the support before the drying step.

[0137] Optionally, the drying step may last for at least 30 minutes. Optionally, the drying step may last for at least 2 hours. Optionally, the drying step may last for 3 hours or longer.

[0138] As the amine-containing adsorbent particles gradually dry, they self-bind to the attachment surface of the support.

[0139] A method for replacing the adsorbent particles described above includes the step of flushing the support with an aqueous fluid to remove any amine-containing adsorbent particles from the adhesion surface; then

[0140] Implement the steps described above for manufacturing the carbon dioxide removal structure.

[0141] Preferably, the aqueous fluid is water.

[0142] A direct air carbon capture (DAC) system includes one or more adsorber containers, wherein at least one of the adsorber containers includes the carbon dioxide removal structure described above.

[0143] Various other features and aspects of the invention are defined in the claims.

[0144] Unless otherwise defined, all technical and scientific terms used herein have the meanings commonly understood by one of ordinary skill in the art to which this invention pertains.

[0145] The term "halogenated polymer" refers to a polymer formed by polymerization of at least one halogen-containing monomer. Polymerization may include one or more halogen-free monomers. Those skilled in the art will understand that not all halogens are useful in this regard, and that halogenated polymers generally contain common halogen elements such as fluorine, chlorine, and bromine. Preferably, the term "halogenated polymer" refers to a polymer containing one or more of fluorine, chlorine, and bromine.

[0146] The term "fluoropolymer" refers to a halogenated polymer in which at least one halogen atom in the structure of the precursor halogenated monomer is fluorine. Attached Figure Description

[0147] Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which the same parts are provided with corresponding reference numerals, and in the drawings:

[0148] Figure 1 This is a schematic diagram of an integral structure according to one aspect of the present invention;

[0149] Figure 2 This is a graph showing the triboelectric charge density (TECD) of various materials under vacuum conditions (i.e., the vacuum triboelectric surface charge density of the material). The error bar represents the standard deviation, n=5 independent samples. This graph is reproduced from the following literature without modification under a Creative Commons Attribution 4.0 International License: Lui et al. Standardized measurement of dielectric materials' intrinsic triboelectric charge density through the suppression of air breakdown. Nature Communications. (2022) Oct;13(1):6019.DOI: 10.1038 / s41467-022-33766-z. PMID: 36224185; PMCID: PMC9556570. This license allows for use, sharing, adaptation, distribution and reproduction in any media or format, provided that you properly attribute the original author and source, provide a link to the Creative Commons license, and indicate whether modifications have been made. To view a copy of this license, see http: / / creativecommons.org / licenses / by / 4.0 / .

[0150] Figure 3a This is an image of adsorbent beads (approximately 0.5 mm in diameter) that self-adhere to the inner surface of a 6 mm OD (4 mm ID) PTFE tube manufactured according to the present invention. Figure 3c Figure 3d is an image of adsorbent beads coated on a PFA tube (6 mm OD; 4 mm ID) manufactured according to the present invention;

[0151] Figure 4This is a graph showing the breakthrough curve of the adsorbent bonded to a 307 mm PTFE tube (4 mm ID). Mass of dried adsorbent: 0.49 g; humidity: 50%; temperature: 21 °C.

[0152] Figure 5 This is a schematic diagram of a layered sheet system with a thin plate or laminate according to the present invention. The thin metal sheet is coated with a fluoropolymer, and alternating channels are used for heating fluid, thereby eliminating the need for steam regeneration.

[0153] Figure 6 This is a graph showing the breakthrough curves of ion exchange resin adsorbents electrostatically bonded to 150 mm FEP and PFA (4 mm ID). Flow rate 0.51 L / min; humidity 50%; temperature 21°C; and

[0154] Figure 7a It is another layered sheet or board system. Figure 7b yes Figure 7a The cross-section aa with an internal network structure Figure 7c yes Figure 7a The cross-section aa that does not have an internal network structure; and

[0155] Figure 8a and Figure 8b This is an image of adsorbent beads (without adhesive) coated on a 100-micron FEP sheet according to the present invention. Figure 8a With aluminum foil backing, Figure 8b No aluminum foil backing; and

[0156] Figure 9This is a schematic diagram illustrating an apparatus and method for measuring the triboelectric charge density of materials according to the present invention. The diagram is reproduced without modification from the following document under a Creative Commons Attribution 4.0 International License: Lui et al. Standardized measurement of dielectric materials' intrinsic triboelectric charge density through the suppression of air breakdown. Nature Communications. (2022) Oct;13(1):6019. DOI: 10.1038 / s41467-022-33766-z. PMID: 36224185; PMCID:PMC9556570. This license allows for use, sharing, adaptation, distribution, and reproduction in any media or format, provided that you properly attribute the original author and source, provide a link to the Creative Commons license, and indicate whether modifications have been made. To view a copy of this license, see [link to Creative Commons Attribution 4.0 International License]. http: / / creativecommons.org / licenses / by / 4.0 / . Detailed Implementation

[0157] A carbon dioxide removal structure 1 according to the present invention, in this embodiment, the structure is in the form of an integral structure 2, such as... Figure 1 As shown. In this embodiment, the monolithic structure 2 is designed to have a series of parallel channels 3 through which air can flow. However, it should be understood that alternative designs known in the art (e.g., cellular designs) can be used to engineer the monolithic structure 2. This design ensures a relatively uniform airflow distribution through the channels 3.

[0158] The integral body 2 is made of ceramic material, and the inner wall 4 of the channel 3 is coated with polytetrafluoroethylene (PTFE) to provide an adhesion surface 5. Figure 2 As shown, the vacuum triboelectric surface charge density of PTFE is -853.7 μCm. -2 .

[0159] Although in this embodiment, the inner wall 4 of the channel 3 is coated to provide an adhesion surface 5, if the integral structure 1 is made of a vacuum triboelectric surface with a charge density of -150 μCm -2 It can be made of a larger (i.e., higher negative charge density) material—or if surface 2 is induced to have such a vacuum triboelectric surface charge density—so that a separate coating is not required, and the inner wall 4 is the attached surface 5.

[0160] An adsorbent material comprises a plurality of adsorbent particles in the form of amine-containing anion exchange resin beads 6, the adsorbent material being disposed on an attachment surface 5. In this embodiment, the adsorbent beads 6 are microporous divinylbenzene crosslinked polymers in the form of spherical beads having primary amine groups. The adsorbent material can adsorb carbon dioxide from ambient air.

[0161] Anion exchange resin beads 6 are assembled in an organized manner on the attachment surface 5 without a binder. The adsorbent beads 6 self-bind to and assemble on the attachment surface 5 to provide a uniform distribution of beads 6 on the surface. Without being bound by theory, it is assumed that the difference in triboelectric charge density between the beads 6 and the attachment surface 5 causes the beads to self-assemble in an organized manner on the attachment surface. Further, it is assumed that the binding force is essentially an electrostatic force (and / or van der Waals force), which, in addition to binding the adsorbent beads to the PTFE surface, tends to repel adjacent adsorbent beads. This means that the beads do not aggregate but tend to be distributed in a monolayer of isolated material on the surface, with gaps between the beads, thus producing a degree of coating uniformity. Typically, 50-60% of the surface is covered by anion exchange resin beads 6.

[0162] During use, ambient air flows through channel 3 and comes into close contact with adsorbent beads 6 assembled on the attachment surface 5. Carbon dioxide present in the ambient air is adsorbed by the ambient beads, resulting in a lower carbon dioxide content in the air leaving channel 3 than when it entered channel 3.

[0163] An alternative embodiment of the present invention is as follows: Figure 5 As shown. In this embodiment, the support structure of the carbon dioxide removal structure 1' is formed by a plurality of parallel plates 7 held in a frame 8. Channels 3' are formed between the plates 7, and alternating channels are used for airflow (from which carbon dioxide is removed) and heating fluid (e.g., steam). In practice, this means that the airflow path passes through each of the formed alternating channels. Gaskets can be arranged to ensure a suitable airflow path. This embodiment is based on a plate heat exchanger structure. In this embodiment, the plates 7 are metal, and the outer planar surface 4' of the plates 7 is coated with PFA (or other suitable surface coatings according to the invention and disclosed herein), but it should be understood that the plates can also be formed of PFA (or other suitable materials). A particular advantage of the plate form is that it can be easily and uniformly coated if a suitable adhesion surface 5' is required. Typically, the anion exchange resin beads 6' cover 50-60% of the adhesion surface 5'.

[0164] An adsorbent material comprising a plurality of adsorbent particles in the form of amine-containing adsorbent beads 6' disposed on an attachment surface 5'. In this embodiment, the adsorbent anion exchange resin beads 6 are made of a polymer in the form of spherical beads, more particularly an amine-functionalized polymer resin. The adsorbent material can adsorb carbon dioxide from ambient air.

[0165] Besides the advantage of the plate form, where plate 7 can be easily coated with fluoropolymers, it also means that alternating channels can be used for heating fluid, thus eliminating the need for steam regeneration (reducing the risk of beads accidentally detaching from the adhesion surface). Advantageously, by incorporating the heating fluid on one side of the plate, this also applies a charge to the gas / air side of the plate, thereby further enhancing the adhesion of beads 6' to the adhesion surface 5'.

[0166] In use, ambient air flows through alternating channels 3', while heating fluid (steam or hot water) can flow through the remaining channels. The ambient air comes into close contact with the adsorbent beads 6' assembled on the attachment surface 5'. Steam or hot water does not come into close or direct contact with the beads 6' assembled on the attachment surface 5' because the plate structure allows for heating of the beads 6'. Carbon dioxide present in the ambient air is adsorbed by the ambient beads, resulting in a lower carbon dioxide content in the air leaving channel 3' compared to its entry into channel 3'.

[0167] Another similar implementation is as follows Figures 7a to 7c As shown. Similarly, this is a layered sheet or plate system. The support structure of the carbon dioxide removal structure 1” is formed by multiple parallel plates 7”. The plates 7” are arranged to provide two interlocking or staggered fluid flow paths. As shown in Figure 7c As can be seen more clearly, spacer elements 10” can be included between the plates to maintain a gap between the surfaces (3 mm in this case). The path formed by the interlaced channels 3a” creates an airflow path that allows air to flow into structure 1” and travel through the alternating channels. Another set of interlaced channels 3b” forms a heating / cooling path through which fluids (e.g., steam or hot water) can flow. This is achieved through… Figure 7aThe arrows in the diagram more clearly illustrate how the fluid flow paths are arranged so that the heating / cooling fluid flows through alternating channels. Since the airflow and heating paths are interleaved channels 3a”, 3b (i.e., alternating parallel channels used for either airflow or heating), this means that plate 7” can have adsorbent 6” on one side and be heated from the other. Because the plates have good thermal conductivity (in this case, they are 0.4 mm thick metal plates with a 0.1 mm fluoropolymer coating), and the adsorbent beads 6” are assembled in a layered form (held electrostatically to the fluoropolymer coating) on ​​one surface of the plate (so that most of the adsorbent is in contact with plate 7” via the attachment surface 5”), the adsorbent can be easily and quickly heated by allowing the heating fluid to flow through the heating path without direct contact with the heating fluid (e.g., steam or hot water). Heat is conducted from the heating fluid (e.g., steam) in contact with one surface of plate 7” to the layer of adsorbent beads 6” arranged on the opposite surface of plate 7”.

[0168] In this embodiment, plate 7” is metal, and its outer planar surface 4” is coated with FEP (or other suitable surface coatings according to the invention and disclosed herein), but it should be understood that the plate can also be formed of FEP (or other suitable materials). A particular advantage of the plate form is that it can be easily and uniformly coated if a suitable adhesion surface 5” is required. An adsorbent material comprising a plurality of adsorbent particles in the form of positively charged adsorbent beads 6’ disposed on the adhesion surface 5’. In this embodiment, the adsorbent beads 6 are made of a polymer, more particularly an amine-functionalized polymer resin, in the form of spherical beads. The adsorbent material can adsorb carbon dioxide from ambient air.

[0169] like Figure 7b As shown, the fine mesh cage 8” can be used to provide a secondary support structure for the beads. If the system is to be used in challenging environments, this can further help retain the adsorbent particles (in this case, amine-functionalized ion exchange resin beads) on the support surface. In this embodiment, the mesh cage 8” is removable to allow for easy removal and replacement of the beads. Mesh end caps 9” can also be provided at the ends of the elongated channels. The mesh end caps 9” can be useful during the manufacture of the sheet system 1”, as discussed further below.

[0170] It is worth noting that the secondary support structure can be used in other embodiments. The mesh cage 8” forming the optional secondary support 8” can also be positively charged. This can induce stronger adhesion to the attachment surface when one does not wish to be bound by theory.

[0171] Layered sheet or plate systems are known in the art, for example, WO2021239747A1 describes such structures that can be adapted according to the present invention, and is incorporated herein by reference.

[0172] Adsorbent

[0173] Amine-containing adsorbent particles are known in the art and are capable of reacting with and binding to carbon dioxide. They can be tailored or even optimized for direct air capture (DAC). Surface modification can be achieved through impregnation, grafting, and / or bonding of amine functional groups (especially primary and / or secondary amine functional groups). The adsorbent material can be an amine-functionalized solid adsorbent. For example, the material can be a weak base ion exchange resin and / or amine-functionalized cellulose and / or amine-functionalized silica and / or amine-functionalized carbon and / or amine-functionalized metal-organic framework and / or other amine-functionalized polymer adsorbents. Another adsorbent material suitable for the present invention can be amine-functionalized cellulose. The solid inorganic or organic, non-polymer or polymer matrix of the particles can be an organic or inorganic polymer support, preferably an organic polymer support, particularly a polystyrene-based material, preferably a styrene-divinylbenzene copolymer, thereby preferably forming an adsorbent material surface functionalized with a primary amine (e.g., methylamine or benzylamine moiety). Polymer resins having amine functional groups can be formed into bead shapes.

[0174] manufacture

[0175] An exemplary method for manufacturing the monolithic structure 2 and carbon dioxide removal structure 1 described above is as follows. Adsorbent anion exchange resin beads 6 are loaded into the monolithic structure 1 by injection in the form of adsorbent beads 6 / water slurry. Excess water is drained from the tube and the monolithic structure 1, and the beads 6 are dried in a vacuum oven at 80°C. As the beads gradually dry, they self-bond to the attachment surface 5 of the monolithic structure 2. After approximately 3 hours of drying, the monolithic structure 2 is removed from the oven and gently stirred, thereby uniformly coating the inner wall 4 of the monolithic structure 2 with adsorbent beads 6. The beads can be stirred by vibrating the monolithic structure or by dispersing them through channels using an airflow.

[0176] Multiple parallel plates for layered sheet or plate systems can be manufactured using similar exemplary methods. In a preferred embodiment, the plates form two interlocking or staggered fluid flow paths. Adsorbent anion exchange resin beads 6 are coated onto the plates in the form of adsorbent beads 6' / water slurry. Excess water is drained from plates 7, 7" and the anion exchange resin beads 6' are dried. In a preferred embodiment, a mesh end cap 9" is disposed at one end of a channel that will be an airflow channel and has adsorbent beads present on the walls of plate 7". A slurry of beads and water is loaded into the airflow channel. The mesh end cap 9" retains the beads based on size and allows water to flow through, such that the channel can be filled with the bead mixture. The retained bead mixture can then be dried by raising the temperature to 80°C.

[0177] In a preferred form of this method, the heat transfer fluid present in the alternating heating channels can itself be used to dry the beads (in a manner similar to that used for regeneration). Such a system is likely preferred because, unlike many monolithic structural systems, layered sheet or plate systems do not require steam regeneration, where steam comes into direct contact with the anion exchange resin beads. As the beads gradually dry, they self-bond to the adhesion surfaces 5', 5' of plates 7, 7". After approximately 30 minutes of drying, plates 7, 7" have a uniform coating of adsorbent beads 6', 6" on their adhesion surfaces 5', 5'.

[0178] It should be understood that higher temperatures can be used and drying time can be reduced.

[0179] Similarly, a lower temperature can be used and the drying time can be increased.

[0180] A vacuum oven can help with this process, but it is not necessary.

[0181] Adsorbent replacement

[0182] Chemical binders are an additional cost to the manufacture of conventional carbon dioxide removal structures, such as monolithic structures or layered sheet / plate systems. Generally, binders have no active function in carbon capture other than binding the active material (adsorbent) to the walls through which the gas will pass. Furthermore, chemical binders can clog activated carbon capture sites, thereby impairing adsorbent performance. Binders can also cause problems because they must withstand temperature cycling, which causes thermal expansion / contraction of the underlying structure, leading to detachment of the adsorbent and binder layers from the monolithic structure. Moreover, typical amine adsorbents expand and contract with the adsorption and desorption of CO2 as well as water vapor, further limiting the binder's capabilities. In this invention, the absence of chemical binders eliminates the detrimental effects of expansion / contraction associated with adsorption / desorption and temperature cycling. It also eliminates the detrimental effects of binders clogging pores / active sites.

[0183] The absence of chemical binders also allows for easy replacement of deactivated adsorbent by simply rinsing the channels with water. This removes the active component (adsorbent), leaving the carbon dioxide removal structure (e.g., monolithic structure, bed, or sheet / plate structure) intact. In a typical monolithic structure, when the active component becomes deactivated, either the entire monolithic structure must be replaced, or the active component can be burned off by the high-temperature treatment of the monolithic structure. Similar regeneration challenges apply to sheet / plate systems. This increases costs, operational downtime, and additional waste. This invention allows the carbon dioxide regeneration support structure below to be reused multiple times by simply rinsing with water to remove old adsorbent particles and then (e.g., using the manufacturing method described above) replenishing new adsorbent particles.

[0184] Examples include layered sheet / monolithic structures composed entirely of adsorbent. However, these structures can be subjected to stress due to expansion / contraction, which can lead to cracking and degradation of the layered / monolithic structure. In this invention, the adsorbent particles, preferably spherical adsorbent beads, can expand and contract without causing structural damage to the beads.

[0185] Selection of Adhesion Surface Material

[0186] The selection of materials for the adhesion surface (on which amine-containing adsorbent particles will self-assemble even in the absence of an adhesive) is based on the triboelectric charge density measured under vacuum conditions (referred to herein as “vacuum triboelectric charge density” or “vacuum TECD”). As described in the article by Lui et al. (Lui et al. Standardized measurement of dielectric materials' intrinsic triboelectric charge density through the suppression of air breakdown. Nature Communications. (2022) Oct;13(1):6019.DOI: 10.1038 / s41467-022-33766-z. PMID: 36224185; PMCID: PMC9556570, the full text of which and related supplemental information are incorporated herein by reference), the triboelectric charge density is measured under vacuum conditions (preferably, a vacuum pressure of about 5 × 10⁻⁶). -5 Measured at Pa (or lower).

[0187] Vacuum TECD of the material can be measured by incorporating it into a contact-separation triboelectric generator (TENG) and then measuring the triboelectric charge density under vacuum conditions as described below: Part 1: The material is cut into a circular shape (e.g., diameter: 20 mm; thickness: 3 mm) using a laser cutter (PLS6.75, Universal Laser System). An iron plate (diameter: 20 mm; thickness: 0.1 mm) is adhered to the surface as an electrode layer (the iron electrode has high temperature stability and high hardness, minimizing material transfer). Part 2: A circular material is cut (diameter: 15 mm; thickness: 3 mm). An iron plate (diameter: 15 mm; thickness: 0.1 mm) is adhered to the surface of the substrate material as the electrode layer. The substrate material is then adhered to the surface of the electrode layer as the triboelectric layer. The iron electrode can be obtained by cutting an iron plate and sanding it. The two metal plates are connected by a high-temperature resistant wire for electrical measurement.

[0188] A high-vacuum system with a heater is used to provide a stable operating environment. Low atmospheric pressure can be achieved using a mechanical pump, and pressure regulation can be achieved by combining it with an adjustable inlet. A molecular pump is used to achieve high vacuum conditions (the ultimate vacuum of a molecular pump is approximately 5 × 10⁻⁶). -5 Pa). Before testing, the sample is placed in a high vacuum system until the molecular pump reaches its ultimate vacuum, and then kept in a steady state for 2 hours with the vacuum gauge turned off (the vacuum gauge can generate ions that have little impact on environmental conditions). Equilibrium will be reached within 2 hours as the temperature changes. The vacuum is monitored using a vacuum ionization gauge. The temperature is monitored using a vacuum thermocouple gauge. The output charge and voltage of the substrate material are measured using an electrometer (e.g., Keithley 6514). The energy density is calculated as the ratio of output energy to geometric area. The induced charge (σ) measured in vacuum... I ) represents TECD (σ T Charge density measurement equipment and methods, such as... Figure 9 As shown.

[0189] By avoiding charge loss caused by air breakdown and thermionic emission effects, Lui et al. used a standardized strategy to test the TECD of more than 40 dielectric materials with iron electrodes, as iron electrodes exhibit high-temperature stability and high hardness, minimizing material transfer. The initial surface charge on the triboelectric layer was removed using anhydrous ethanol. Five materials of different thicknesses were tested, further demonstrating the effectiveness of this method in reducing σc. TThe thickness of the substrate material is irrelevant. Furthermore, to eliminate the randomness of testing individual samples, each material was tested with five different samples, and the corresponding values ​​were recorded and plotted. Figure 2 The negative and positive charge densities indicate whether the material will acquire a negative or positive charge when in contact with an iron electrode. For example, polyvinyl chloride (PVC) and PTFE tend to gain electrons, while polyurethane (PU) and cellulose tend to lose electrons. This differs from the traditional triboelectric series, which only considers the polarity of the material, because both polarity and the amount of transferred charge are taken into account.

[0190] Those skilled in the art will also understand that the material chosen for the attachment surface must also be suitable for use as an attachment surface in a DAC system. For example, it must be structurally capable of withstanding temperatures suitable for adsorbent regeneration (typically in the range of 80-120°C).

[0191] Experimental work

[0192] by Figure 2 Using the triboelectric charge density diagram as a reference, a set of tests was conducted to demonstrate the suitability of different materials as attachment surfaces for the DAC (as a coating on a support or as one or more elements forming the support). It should be understood that the material also needs to be suitable for inclusion in the structure either as a structural material or as a coating, and needs to be able to withstand the temperatures used in the DAC, i.e., stable at temperatures up to 100°C.

[0193] PTFE

[0194] Experiments were conducted using PTFE tubes of a single length loaded with adsorbent beads. Commercially, multiple parallel channels can be used in monolithic structures. Results obtained in a single channel can be linearly scaled up, applicable to a range of structures, including monolithic structures and layered sheet / plate systems.

[0195] Adsorbent beads (commercially available amine-loaded anion exchange resin) were injected into a PTFE tube (307 mm) as an adsorbent bead / water slurry. Excess water was drained from the tube, and the beads were dried in a vacuum oven at 80°C. As the beads gradually dried, they self-bonded to the inner surface of the tube. After drying (3 hours), the PTFE tube was removed from the oven and gently shaken, causing the adsorbent to be evenly coated onto the inner wall of the tube. Figure 3a The same experiment was performed using perfluoroalkoxyalkane (PFA) tubes (OD: 6 mm; ID: 4 mm), and the results are as follows. Figure 3b and Figure 3cAs shown in Figure 3, the binding force appears to be essentially an electrostatic force (and / or van der Waals force), which, in addition to binding the adsorbent particles to the PTFE surface, tends to repel adjacent adsorbent particles. This means that the beads do not aggregate and tend to be distributed in a monolayer isolated on the surface, with gaps between the beads, resulting in a uniform coating.

[0196] Connect the PTFE tubing to a humid airflow (0.25 L / min, 410 ppm CO2, 50% RH) and measure the CO2 concentration in the bed exhaust. Figure 4 The adsorbent bed was regenerated in a vacuum oven, and the experiment was repeated with double the air flow rate (0.51 L / min).

[0197] After the adsorption test is completed, the adsorbent can be easily removed from the tube by rinsing with water.

[0198] Table 1 summarizes the results. The CO2 uptake (to 100% breakthrough) was similar for both flow rates, indicating that the equilibrium uptake at 21 °C and 50% RH was 1.71 mol / kg.

[0199] Table 1: Summary of Penetration Experiments

[0200] FEP (Fluoroethylene propylene) and PFA (Perfluoroalkoxyalkane)

[0201] As in previous experiments, adsorbent materials containing anion exchange resin particles were loaded into tubes simulating monolithic structures, beds, or layered / sheet structures on the inner wall. Anion exchange resin adsorbents with primary amine functional groups (more specifically, macroporous polystyrene crosslinked with divinylbenzene) were loaded in their fresh, "wet" form (i.e., bound to water) into 170 mm FEP tubes with a 6 mm outer diameter (OD) (4 mm inner diameter (ID)). Glass wool was used at the top and bottom of the tubes to prevent adsorbent loss. Excluding the glass wool, the usable tube length for the adsorbent coating was 150 mm. After drying in a vacuum oven at 80°C and 1 mbar (for 3 hours), the adsorbent beads were dispersed to form a uniformly formed adsorbent bead coating on the inner surface of the FEP tubes.

[0202] The same experiment was performed using PFA tubes.

[0203] After regeneration, the adsorption of the tube containing the adsorbent was tested using a moist stream of air containing 420 ppm CO2. A summary of the experimental conditions and results is shown in Table 2.

[0204] Table 2: Screening results of substrate materials at 21℃ and 50%RH.

[0205] The breakthrough curve of the anion exchange resin is as follows: Figure 6 As shown. The air flow rate containing 420 ppm carbon dioxide was 0.51 L / min; the humidity was 50%; and the temperature was 21℃.

[0206] It is worth noting that when the adsorbent beads are arranged on the attachment surface, this allows for effective heating, which allows regeneration to occur within 40 minutes (or less), instead of the usual 3 or 4 hours required in packed bed systems.

[0207] Similar experiments were also conducted on FEP sheets instead of tubes to demonstrate that the beads self-assemble on substantially flat or flat surfaces (although said surfaces may have variations in surface roughness). Amine-functionalized adsorbent beads (without chemical binders) were coated onto 100-micron FEP sheets. Excess water was drained from the tubes, and the beads were dried at 80°C. As the beads gradually dried, they self-bonded to the surface of the sheet. Results can be seen in… Figure 8a and Figure 8b As seen in, Figure 8a The medium-sized sheet has an aluminum foil backing, in Figure 8b The FEP sheet has no backing. This indicates that the method is equally applicable to layered / laminated or sheet systems.

[0208] All features disclosed in this specification (including any appended claims, abstract, and drawings) and / or all steps of any method or process so disclosed may be combined in any combination, except that at least some of such features and / or steps are mutually exclusive combinations. Unless expressly stated otherwise, each feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Therefore, unless expressly stated otherwise, each disclosed feature is merely one example of a series of equivalent or similar features. The invention is not limited to the details of one or more of the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification (including any appended claims, abstract, and drawings), or any novel feature or any novel combination of steps of any method or process so disclosed.

[0209] Regarding the use of virtually any plural and / or singular terms in this document, those skilled in the art can translate from plural to singular and / or from singular to plural depending on the context and / or application. For clarity, various singular / plural permutations may be explicitly described herein.

[0210] Those skilled in the art will understand that, in general, the terms used herein, and especially those used in the appended claims, are intended to be “open-ended” terms (e.g., the terms “including” or “comprising” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “at least having,” and the term “includes” should be interpreted as “including but not limited to,” etc.). Those skilled in the art will further understand that if it is intended to introduce a particular number of claims, this intention will be expressly stated in the claims, and where such a statement is absent, this intention does not exist. For example, to aid understanding, the appended claims may contain the use of introductory phrases such as “at least one” and “one or more” to introduce the claims. However, the use of such phrases should not be construed as implying that introducing a claim recitation by the indefinite article "a / an" limits any particular claim containing such an introduced claim recitation to an embodiment containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a / an" (e.g., "a / an" should be interpreted as meaning "at least one / an" or "one / an or more / an"); the same applies to the use of definite articles used to introduce a claim recitation. Furthermore, even when a specific number of introduced claim recitations is explicitly stated, those skilled in the art will recognize that such recitations should be interpreted as indicating at least the number of recitations (e.g., in the absence of other modifiers, simply stating "two recitations" means at least two recitations, or two or more recitations).

[0211] It should be understood that various embodiments of this disclosure have been described herein for illustrative purposes, and various modifications may be made without departing from the scope of this disclosure. Therefore, the various embodiments disclosed herein are not intended to be limiting, and the true scope is indicated by the appended claims.

Claims

1. A carbon dioxide removal structure for separating gaseous carbon dioxide from a gas mixture containing gaseous carbon dioxide, comprising: A support having at least one attachment surface, wherein the negative vacuum triboelectric surface charge density of the at least one attachment surface is less than -150 µC m -2 ; Multiple amine-containing adsorbent particles, said adsorbent particles being capable of adsorbing or binding carbon dioxide; The plurality of amine-containing adsorbent particles self-assemble on at least one attachment surface of the support.

2. The carbon dioxide removal structure according to claim 1, wherein the negative vacuum triboelectric surface charge density is measured in a vacuum.

3. The carbon dioxide removal structure according to claim 1 or 2, wherein the negative vacuum triboelectric surface charge density is measured at a temperature of 400 Kelvin (400 K) or lower.

4. The carbon dioxide removal structure according to any one of the preceding claims, wherein an iron electrode is used for measuring the negative vacuum triboelectric surface charge density.

5. A carbon dioxide removal structure for separating gaseous carbon dioxide from a gas mixture containing gaseous carbon dioxide, comprising: A support having at least one attachment surface, said attachment surface being a material selected from the group consisting of: Halogenated polymers; Polyimide; Polysulfone; Polystyrene; Silicone rubber; Quartz glass; Cellulose acetate tablets; Polyethylene; and Multiple amine-containing adsorbent particles, said adsorbent particles being capable of adsorbing or binding carbon dioxide; Multiple amine-containing adsorbent particles self-assemble on at least one attachment surface of the support.

6. The carbon dioxide removal structure according to any one of the preceding claims, wherein the gas mixture containing the gaseous carbon dioxide is ambient air.

7. The carbon dioxide removal structure according to any one of the preceding claims, wherein the support is a solid substrate, such as an integral structure, or wherein the support comprises one or more layered plates or sheets.

8. The carbon dioxide removal structure according to any one of the preceding claims, wherein the adhesion surface is a coating.

9. The carbon dioxide removal structure according to any one of the preceding claims, wherein at least the attachment surface comprises a halogenated polymer or a halogenated polymer.

10. The carbon dioxide removal structure according to any one of the preceding claims, wherein the adhesion surface comprises a material selected from the group consisting of: Polyvinyl chloride (PVC); Polytetrafluoroethylene (PTFE); Polypropylene; Acrylonitrile butadiene styrene; Polyphenylene sulfide; Acetaldehyde; Polyethylene; Cellulose acetate tablets; Quartz glass; Polydichloroethylene; Polyvinylidene fluoride; Silicone rubber; Fluorinated ethylene propylene (FEP); Polystyrene; Polysulfone; Fluororubber; Polyimide; Polyetheretherketone; Polytetrafluoroethylene; Polyvinyl chloride; Perfluoroalkoxy (PFA).

11. The carbon dioxide removal structure according to any one of the preceding claims, wherein the attachment surface is polytetrafluoroethylene (PTFE).

12. The carbon dioxide removal structure according to any one of the preceding claims, wherein the attachment surface is fluorinated ethylene propylene (FEP).

13. The carbon dioxide removal structure according to any one of the preceding claims, wherein the attachment surface is perfluoroalkoxy (PFA).

14. The carbon dioxide removal structure according to any one of the preceding claims, wherein the amine-containing adsorbent particles comprise a commercial anion exchange resin and / or a metal-organic framework (MOF).

15. The carbon dioxide removal structure according to any one of the preceding claims, wherein the amine-containing adsorbent particles are uniformly distributed on at least one attachment surface of the support.

16. The carbon dioxide removal structure according to any one of the preceding claims, wherein no chemical binder is present (or in trace amounts that do not have significant binding activity between the amine-containing adsorbent particles and the attachment surface of the support).

17. The carbon dioxide removal structure according to any one of the preceding claims, wherein the support comprises a plurality of plates, wherein at least a portion of the surface of the plates is an attachment surface, and a plurality of channels are formed between the plates.

18. The carbon dioxide removal structure of claim 17, wherein the channels are interleaved to form air channels and separate heating fluid channels using alternating channels.

19. The carbon dioxide removal structure according to claim 17 or 18, wherein a secondary support structure is provided on the side of the amine-containing adsorbent particles opposite to the attachment surface.

20. The carbon dioxide removal structure according to any one of claims 17 to 19, wherein the secondary support structure is configured as a mesh structure, and the mesh structure may be a mesh cage.

21. A method for manufacturing a carbon dioxide removal structure according to any one of claims 1 to 20, comprising: A slurry is injected into a support having one or more attachment surfaces. The slurry contains a plurality of amine-containing adsorbent particles and an aqueous fluid, wherein the adsorbent particles are capable of adsorbing or binding carbon dioxide. The slurry is dried to remove most of the aqueous fluid. This causes the amine-containing adsorbent particles to coat the one or more adhesion surfaces.

22. The method for manufacturing a carbon dioxide removal structure according to claim 21, wherein the drying step is performed at a high temperature preferably 80 degrees Celsius (80°C).

23. The method of manufacturing a carbon dioxide removal structure according to claim 21 or 22, wherein any excess aqueous fluid is discharged from the support prior to the drying step.

24. A method for replacing the adsorbent in a carbon dioxide removal structure according to any one of claims 1 to 20, comprising the step of rinsing a support with an aqueous fluid to remove any amine-containing adsorbent particles from the attachment surface; and then carrying out the steps of manufacturing the carbon dioxide removal structure according to any one of claims 21 to 23.

25. The method for replacing the adsorbent in the carbon dioxide removal structure according to claim 24, wherein the aqueous fluid is water.

26. A direct air carbon capture (DAC) system comprising one or more adsorber containers, wherein at least one of the adsorber containers comprises a carbon dioxide removal structure according to any one of claims 1 to 20.

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