Carbon dioxide adsorption material and method for producing same

Abstract

Disclosed is a carbon dioxide adsorption material which internally contains an amine compound in pores of a porous material. The carbon dioxide adsorption material has a peak pore diameter of not less than 0.4 nm but less than 10 nm, a peak pore volume of 0.003 cm3 / g / nm or more, and an average pore diameter of 1 nm to 30 nm inclusive.

Description

Carbon dioxide adsorption material and method for manufacturing the same

[0001] This invention relates to a carbon dioxide adsorption material and a method for producing the same.

[0002] Conventional attempts have been made to recover carbon dioxide gas using adsorbent materials. Known adsorbent materials include porous or non-porous supports and polyamines filled into or coated on the supports (Patent Document 1 and Non-Patent Document 1).

[0003] JP 2019-507674

[0004] Applied Surface Science, 332 (2015), 167-171, Chao Chen etc., "Polyethylenimine-incorporated zeolite 13X with mesoporosity forpost-combustion CO2capture"

[0005] However, the inventors of this invention have found that while conventional carbon dioxide adsorption materials adsorb carbon dioxide using polyamines, a new problem arises: the low adsorption rate. In carbon dioxide adsorption, increasing the adsorption rate is important for improving air quality in enclosed spaces containing high concentrations of carbon dioxide originating from human breath.

[0006] For example, an adsorption material containing a non-porous support 201 and a polyamine 202 coated on the support 201 has a structure as shown in Figure 13, and because of its limited surface area, it was not possible to achieve a sufficiently high adsorption rate.

[0007] Therefore, as disclosed in Patent Document 1 and Non-Patent Document 1, even when using a porous material as a support, it was not possible to achieve a sufficiently high adsorption rate.

[0008] For example, the adsorption material containing the porous support 301 and the polyamine 302 filled in the support 301 has a structure as shown in Figure 14, and since it also has a limited surface area, it is thought that it could not achieve a sufficiently high adsorption rate. In more detail, although the surface area of ​​the support 301 itself is large because it is porous, as shown in Figure 15, the polyamine 302 is filled up in the pores, and the area 3020 in the polyamine that can come into contact with carbon dioxide 310 is not sufficiently expanded. As a result, carbon dioxide does not easily diffuse into the pores, and it is thought that the amount of carbon dioxide adsorbed does not increase sufficiently in the initial stages of adsorption (30 minutes or 60 minutes).

[0009] The present invention aims to provide a carbon dioxide adsorption material that has a sufficiently high carbon dioxide adsorption rate.

[0010] The present invention relates to a carbon dioxide adsorption material comprising an amine compound encapsulated within the pores of a porous material, wherein the carbon dioxide adsorption material has a peak pore diameter of 0.4 nm or more and less than 10 nm, and a pore size of 0.003 cm². ３ This invention relates to a carbon dioxide adsorption material having a peak pore capacity of 1 nm to 30 nm and a peak pore capacity of 1 nm to 30 nm.

[0011] The present invention also relates to a method for producing a carbon dioxide adsorbent material, which involves adding an organic solvent solution of an amine compound to a porous material, mixing it, and then heat-treating it to degas the solvent.

[0012] The carbon dioxide adsorption material according to the present invention exhibits a higher adsorption rate. In the carbon dioxide adsorption material according to the present invention, the surface area of ​​the porous material is sufficiently large, and the amine compound is present in the pores of the porous material without being "filled," ensuring a specific pore diameter and pore volume. Therefore, carbon dioxide can easily diffuse into the pores. As a result, the probability of contact between the amine compound and carbon dioxide becomes relatively high, and it is believed that the carbon dioxide adsorption material according to the present invention exhibits a sufficiently high adsorption rate.

[0013] Figure 3 is a schematic cross-sectional view illustrating an example of the structure of the carbon dioxide adsorption material according to the present invention. Figure 4 is a schematic cross-sectional view illustrating the mechanism by which the adsorption rate of the carbon dioxide adsorption material according to the present invention is improved. Figure 5 is a graph of pore diameter-pore capacity showing an example of the pore diameter distribution of the carbon dioxide adsorption material according to the present invention and the conventional carbon dioxide adsorption material. Figure 6 is a graph of elapsed time-carbon dioxide adsorption amount showing an example of the amount of carbon dioxide adsorbed in the initial stages (30 minutes) of adsorption for the carbon dioxide adsorption material according to the present invention and the conventional carbon dioxide adsorption material. Figure 7 is a graph of the total pore capacity of the porous material BET-optimal PEI addition amount showing the optimal PEI addition amount when manufacturing the carbon dioxide adsorption material according to the present invention. Figure 8 is a graph of pore diameter-pore capacity showing the pore diameter distribution of the carbon dioxide adsorption material manufactured in Experimental Example A. Figure 9 is a graph of elapsed time-carbon dioxide adsorption amount showing the amount of carbon dioxide adsorbed in the initial stages (30 minutes) of adsorption for the carbon dioxide adsorption material manufactured in Experimental Example A. 10 is a graph of PEI solution supply amount-carbon dioxide adsorption amount showing the amount of carbon dioxide adsorbed in the initial stages (60 minutes) of adsorption for the carbon dioxide adsorption material manufactured in Experimental Example B. This is a pore diameter-pore capacity graph showing the pore diameter distribution for carbon dioxide adsorption materials manufactured in Experimental Example B (Examples B1 and B2 and Comparative Examples B1 and B2). This is a pore diameter-pore capacity graph showing the pore diameter distribution for carbon dioxide adsorption materials manufactured in Experimental Example B (Example B1 and Comparative Example B3). This is a graph created in Experimental Example C, showing the pore diameter distribution for the carbon dioxide adsorption material of Example B1 and only the porous material of said carbon dioxide adsorption material. This is a graph created in Experimental Example C, showing the pore diameter distribution for the carbon dioxide adsorption material of Example B2 and only the porous material of said carbon dioxide adsorption material. This is a graph created in Experimental Example D, showing an example of the amount of carbon dioxide adsorbed in the initial stages (60 minutes) of adsorption for the carbon dioxide adsorption materials of Example A1 and Comparative Example D1, showing the elapsed time-carbon dioxide adsorption amount graph. This is a schematic cross-sectional view illustrating an example of the structure of a carbon dioxide adsorption material in the prior art. This is a schematic cross-sectional view illustrating an example of the structure of another carbon dioxide adsorption material in the prior art.Figure 14 is a schematic cross-sectional view illustrating the mechanism by which the adsorption rate of the carbon dioxide adsorption material is not sufficiently improved.

[0014] The present invention provides a carbon dioxide adsorption material. The carbon dioxide adsorption material of the present invention comprises a porous material and an amine compound. Specifically, as shown in Figure 1, for example, in the carbon dioxide adsorption material 1 according to the present invention, the amine compound 3 is encapsulated within the pores of the porous material 2. In this specification, "encapsulation" differs from "filling," where the amine compound completely fills (or fills) the pores, and means that the amine compound coats the inner wall of the pores as shown in Figure 1, for example, that it is present in the pores to the extent that it secures the pore diameter (and pore volume) described later. Note that the amine compound 3 is usually present not only in the pores of the porous material 2, as shown in Figure 1, but also in the non-porous regions (or outer surface) of the surface of the porous material 2, covering the entire surface of the porous material 2. Figure 1 is a schematic cross-sectional view illustrating an example of the structure of the carbon dioxide adsorption material of the present invention. Unless otherwise specified, the "up-down direction," "left-right direction," and "front-back direction" used directly or indirectly in this specification correspond to the directions in the figures, respectively. Unless otherwise specified, the same code or symbol shall indicate the same component or have the same meaning, even if their shapes differ.

[0015] The carbon dioxide adsorption material 1 of the present invention contains an amine compound 3 within the pores of a porous material 2, and CO ２ Having a pore size larger than the molecular size, CO ２It becomes possible to diffuse deep into the pores in a short time, and the number of effective adsorption sites for carbon dioxide can be increased. For example, as shown in FIG. 2, the contactable region 30 with carbon dioxide 10 in the amine compound 3 is sufficiently enlarged, and since the pore diameter in the state of encapsulating the amine compound is on the nanoscale, the number (density) of pores can be increased. As a result of these, the number of effective adsorption sites for carbon dioxide can be increased, and the adsorption rate of carbon dioxide can be sufficiently increased. When "filling" is performed such that the amine compound fills (or fills up) the pores, the number of effective adsorption sites for carbon dioxide cannot be increased, so the adsorption rate cannot be sufficiently increased. FIG. 2 is a schematic cross-sectional view for explaining the mechanism by which the adsorption rate of the carbon dioxide adsorption material of the present invention is improved.

[0016] The pore diameter of the carbon dioxide adsorption material of the present invention is 0.4 nm or more and less than 10 nm, and from the viewpoint of further improving the adsorption rate, it is preferably 0.4 nm or more and 5 nm or less, more preferably 0.4 nm or more and 2.5 nm or less, still more preferably 0.5 nm or more and 1.5 nm or less, sufficiently preferably 0.5 nm or more and 1.0 nm or less, and even more sufficiently preferably 0.6 nm or more and 0.9 nm or less. By the carbon dioxide adsorption material of the present invention having such a pore diameter, it can contribute to an increase in the carbon dioxide adsorption amount. If the pore diameter is too small or too large, the adsorption rate decreases.

[0017] The pore volume of the carbon dioxide adsorption material of the present invention is usually 0.003 cm ３ / g / nm or more, and from the viewpoint of further improving the adsorption rate, it is preferably 0.003 cm ３ / g / nm or more and 0.1 cm ３ / g / nm or less, more preferably 0.004 cm ３ / g / nm or more and 0.05 cm ３ / g / nm or less, still more preferably 0.005 cm ３ / g / nm or more and 0.04 cm ３ / g / nm or less, sufficiently preferably 0.006 cm ３ / g / nm or more and 0.03 cm ３ / g / nm or less, even more sufficiently preferably 0.007 cm ３ / g / nm or more 0.02cm ３ / g / nm or less, particularly preferably 0.008 cm ３ / g / nm or more 0.014cm ３ The pore capacity is less than or equal to g / nm. The carbon dioxide adsorption material of the present invention can contribute to an increase in the amount of carbon dioxide adsorbed (especially the adsorption rate) by having such a pore capacity. If the pore capacity is too small, it cannot contribute to an increase in the amount of carbon dioxide adsorbed (especially the adsorption rate). For example, pores with a pore capacity that is too small will not contribute to an increase in the amount of carbon dioxide adsorbed (especially the adsorption rate).

[0018] In this specification, the pore diameter and pore capacity of the carbon dioxide adsorption material are based on values ​​derived from the maximum peak in a pore diameter distribution graph (horizontal axis) - pore capacity (vertical axis), measured by applying the HK method and BJH method to a nitrogen adsorption isotherm. Therefore, the carbon dioxide adsorption material of the present invention has a certain amount or more of pores with a specific pore diameter, thereby sufficiently increasing the adsorption rate. As described above, the "pore diameter" and "pore capacity" of the carbon dioxide adsorption material are based on values ​​derived from the maximum peak in the pore diameter distribution graph, and can therefore be referred to as "peak pore diameter" and "peak pore capacity," respectively.

[0019] The carbon dioxide adsorption material of the present invention may have a particle size distribution in the pore size distribution (horizontal axis - pore volume (vertical axis)) such as that of sample A and sample B shown in Figure 3. For example, in Figure 3, the particle size distribution shown by sample A and sample B has a maximum peak P located within the range of the aforementioned pore size and pore volume. Ａ and P Ｂ It has the following characteristics. In contrast, the particle size distribution shown by sample C has a maximum peak P ＣSince sample C does not fall within the range of pore diameter and pore volume described above, sample C is outside the scope of the present invention. Samples A to C correspond to Examples A1 and B1 and Comparative Example B1, respectively, described later. For this reason, samples A and B, which are within the scope of the present invention, show a sufficiently high carbon dioxide adsorption rate as shown in Figure 4, while sample C, which is outside the scope of the present invention, does not show a sufficiently high carbon dioxide adsorption rate as shown in Figure 4. Figure 3 is a pore diameter-pore volume graph showing an example of the pore diameter distribution of the carbon dioxide adsorption material of the present invention and the conventional carbon dioxide adsorption material. Figure 4 is a graph showing the elapsed time-carbon dioxide adsorption amount, showing an example of the amount of carbon dioxide adsorbed in the initial period (30 minutes) after adsorption started for the carbon dioxide adsorption material of the present invention and the conventional carbon dioxide adsorption material in Figure 3.

[0020] The pore size distribution for measuring the pore diameter and pore capacity of carbon dioxide adsorbent materials can be measured using a gas adsorption analyzer (Microtrac Bel, Belsorp Max X) with adsorbent materials from which water and carbon dioxide have been removed without removing amine compounds. For example, by heating and degassing the adsorbent material at 120°C in an atmospheric environment for 24 hours, and then holding it at 120°C under vacuum for 15 hours, water and carbon dioxide can be removed without removing amine compounds.

[0021] The average pore diameter of the carbon dioxide adsorption material of the present invention is 1 nm to 30 nm, and from the viewpoint of further improving the adsorption rate, it is preferably 3 nm to 25 nm, more preferably 5 nm to 25 nm, very preferably 10 nm to 25 nm, even more preferably 15 nm to 25 nm, and particularly preferably 20 nm to 25 nm. If the average pore diameter is too small or too large, the adsorption rate will decrease.

[0022] In this specification, the average pore diameter of the carbon dioxide adsorbent material is determined by measuring the pore diameter distribution using the same method as described above, and using the average pore diameter obtained for all pores.

[0023] The total pore capacity of the carbon dioxide adsorption material of the present invention is typically 0.005 cm². ３ / g or more 1cm ３ It is less than or equal to / g, and from the viewpoint of further improving the adsorption rate, it is preferably 0.008 cm ３ / g or more 0.8cm ３ less than or equal to 0.01 cm / g, more preferably 0.01 cm ３ / g or more 0.7cm ３ less than or equal to 0.01 cm / g, more preferably 0.01 cm ３ / g or more 0.6cm ３ Less than or equal to / g, preferably 0.01cm ３ / g or more 0.5cm ３ It is less than or equal to / g.

[0024] In this specification, the total pore capacity of the carbon dioxide adsorption material is determined by measuring the pore size distribution using the same method as described above, and using the total pore capacity obtained for all pores.

[0025] The BET specific surface area of ​​the carbon dioxide adsorption material of the present invention is typically 1 m². ２ / g or more 40m ２ The amount is less than or equal to / g, and from the viewpoint of further improving the adsorption rate, preferably 2m ２ / g or more 30m ２ / g or less, more preferably 3m ２ / g or more 30m ２ / g or less, more preferably 10m ２ / g or more 20m ２ It is less than or equal to / g.

[0026] In this specification, the BET specific surface area of ​​carbon dioxide adsorption materials is based on values ​​measured by the following method: The sample is heated and degassed at 120°C in an atmospheric environment for 24 hours, and then held at 120°C under vacuum for 15 hours. After that, the nitrogen adsorption isotherm is measured, and then the BET analytical formula is applied.

[0027] The porous material is not particularly limited as long as it has a large number of pores and can secure the above-mentioned pore diameter and pore volume when an amine compound is encapsulated within the pores. Examples include metal-organic frameworks (MOFs), silica (especially mesoporous silica and fumed silica), zeolites, calcium sulfate, alumina, titania, activated carbon, and diatomaceous earth. From the viewpoint of further improving the adsorption rate, the porous material is preferably MOF, silica (especially mesoporous silica), or zeolite, more preferably MOF or silica (especially mesoporous silica), and even more preferably silica (especially mesoporous silica).

[0028] Mesoporous silica is silica that has a large number of pores. Mesoporous silica is available commercially. Examples of commercially available mesoporous silica include MCM-41 (manufactured by Sigma-Aldrich, mesostructure, type (hexagonal)) and MCM-48 (manufactured by Sigma-Aldrich, mesostructure).

[0029] MOFs are porous materials based on coordinate bonding between organic molecules and metal atoms. More specifically, MOFs are crystalline complexes formed when organic molecules bridge metal atoms (especially metal atom ions) as ligands.

[0030] The organic molecules constituting the MOF may be any organic molecules known in the field of MOFs as capable of constituting an MOF. From the viewpoint of further improving the adsorption rate, the organic molecules preferably include one or more organic molecules selected from the group consisting of azole organic molecules, cyanide organic molecules, and carboxylic acid organic molecules. From a similar viewpoint, the organic molecules more preferably include one or more organic molecules selected from the group consisting of azole organic molecules and cyanide organic molecules, and even more preferably include one or more organic molecules selected from the group consisting of azole organic molecules. Azole organic molecules (especially imidazole organic molecules) have a faster carbon dioxide adsorption rate because the organic molecule and the metal atom are bonded via a nitrogen atom.

[0031] The azole organic molecules constituting the MOF include organic molecules selected from the group consisting of imidazole, benzimidazole, triazole, and purine. From the viewpoint of further improving the adsorption rate, imidazole, benzimidazole, and purine are preferred, more preferably imidazole and benzimidazole, and even more preferably imidazole.

[0032] Azole organic molecules may or may not have substituents. Substituents that azole organic molecules may have include, for example, one or more substituents selected from the group consisting of alkyl groups, halogen atoms, hydrophobic groups such as nitro groups, phenyl groups, pyridyl groups, and cyano groups; and hydrophilic groups such as amino groups and carboxyl groups. Alkyl groups are, for example, alkyl groups having 1 to 5 carbon atoms (particularly 1 to 3 carbon atoms). Specific examples of alkyl groups include, for example, methyl groups, ethyl groups, n-propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, sec-butyl groups, tert-butyl groups, and n-pentyl groups. Examples of halogen atoms include fluorine atoms, chlorine atoms, and bromine atoms.

[0033] From the viewpoint of further improving the adsorption rate, the azole organic molecules constituting the MOF are preferably selected from the group consisting of azole organic molecules without substituents and azole organic molecules having substituents but only hydrophobic groups (particularly alkyl or nitro groups), and more preferably from the group consisting of azole organic molecules having only hydrophobic groups (particularly alkyl groups).

[0034] Examples of azole organic molecules that constitute MOFs include imidazole molecules represented by the following general formula (1), benzimidazole molecules represented by the following general formula (2), triazole molecules represented by the following general formulas (3) and (4), and purine molecules represented by the following general formula (5).

[0035]

[0036] In formula (1), R 1 ~R 3Each of these is independently a hydrogen atom; a hydrophobic group such as an alkyl group, halogen atom, nitro group, phenyl group, pyridyl group, or cyano group; or a hydrophilic group such as an amino group or carboxyl group. From the viewpoint of further improving the adsorption rate, it is preferably a hydrogen atom or the above hydrophobic group, and more preferably a hydrogen atom, alkyl group, halogen atom, nitro group, or cyano group. In a more preferred embodiment from a similar viewpoint, R 1 R is a hydrogen atom, an alkyl group, or a nitro group. 2 and R 3 R is a hydrogen atom, an alkyl group, a halogen atom, or a nitro group. In a more preferred embodiment from a similar viewpoint, R 1 R is an alkyl group, 2 and R 3 It is a hydrogen atom.

[0037] Specific examples of imidazole molecules represented by general formula (1) include the following compounds: imidazole, methylimidazole (especially 2-methylimidazole), ethylimidazole, nitroimidazole, aminoimidazole, chloroimidazole, bromoimidazole, and imidazole carbonitrine.

[0038]

[0039] In formula (2), R 11 ~R 15 Each of these is independently a hydrogen atom; a hydrophobic group such as an alkyl group, halogen atom, nitro group, phenyl group, pyridyl group, or cyano group; or a hydrophilic group such as an amino group or carboxyl group. From the viewpoint of further improving the adsorption rate, it is preferably a hydrogen atom or the above hydrophobic group, and more preferably a hydrogen atom, alkyl group, halogen atom, nitro group, or cyano group. In a more preferred embodiment from a similar viewpoint, R 11 , R 14 and R 15 R is a hydrogen atom, 12 and R 13 Each of these is independently a hydrogen atom, an alkyl group, a halogen atom, or a nitro group.

[0040] Specific examples of benzimidazole molecules represented by general formula (2) include the following compounds: benzimidazole, chlorobenzimidazole, dichlorobenzimidazole, methylbenzimidazole, bromobenzimidazole, nitrobenzimidazole, aminobenzimidazole, and benzimidazole carbonitrile.

[0041]

[0042] In formula (3), R 21 ~R 22 Each of these is independently a hydrogen atom; a hydrophobic group such as an alkyl group, halogen atom, nitro group, phenyl group, pyridyl group, or cyano group; or a hydrophilic group such as an amino group or carboxyl group. From the viewpoint of further improving the adsorption rate, it is preferably a hydrogen atom or the above hydrophobic group, and more preferably a hydrogen atom.

[0043] Specific examples of triazole molecules represented by general formula (3) include, for example, the following compound: 1,2,3-triazole.

[0044]

[0045] In formula (4), R 31 ~R 32 Each of these is independently a hydrogen atom; a hydrophobic group such as an alkyl group, halogen atom, nitro group, phenyl group, pyridyl group, or cyano group; or a hydrophilic group such as an amino group or carboxyl group. From the viewpoint of further improving the adsorption rate, it is preferably a hydrogen atom or the above hydrophobic group, and more preferably a hydrogen atom.

[0046] Specific examples of triazole molecules represented by general formula (4) include, for example, the following compound: 1,2,4-triazole.

[0047]

[0048] In formula (5), R 41 ~R 43Each of these is independently a hydrogen atom; a hydrophobic group such as an alkyl group, halogen atom, nitro group, phenyl group, pyridyl group, or cyano group; or a hydrophilic group such as an amino group or carboxyl group. From the viewpoint of further improving the adsorption rate, it is preferably a hydrogen atom or the above hydrophobic group, and more preferably a hydrogen atom.

[0049] Specific examples of purine molecules represented by general formula (5) include the following compounds: purines.

[0050] Cyanide-based organic molecules such as potassium ferricyanide, potassium ferrocyanide, and hydrogen cyanide can be used. Carboxylic acid-based organic molecules such as terephthalic acid, benzenetricarboxylic acid, and benzenedicarboxylic acid can be used.

[0051] The metal atoms constituting the MOF are selected from the group consisting of, for example, zinc atoms, copper atoms, nickel atoms, iron atoms, indium atoms, aluminum atoms, cobalt atoms, praseodymium atoms, cadmium atoms, mercury atoms, and manganese atoms. From the viewpoint of further improving the adsorption rate, they are preferably selected from the group consisting of zinc atoms, cobalt atoms, and iron atoms, more preferably from the group consisting of zinc atoms and cobalt atoms, and even more preferably zinc atoms. The compounds that supply such metal atoms are not particularly limited and include, for example, zinc nitrate, copper nitrate, aluminum nitrate, nickel nitrate, and the like.

[0052] The combination of organic molecules and metal atoms in MOFs is not particularly limited, but from the viewpoint of further improving the adsorption rate, the following combinations (C1) to (C3) are preferred, and the following combination (C1) is preferred: Combination (C1) = A combination of an imidazole molecule represented by general formula (1) (particularly 2-methylimidazole and / or nitroimidazole) and one or more metal atoms selected from the group consisting of zinc atoms and iron atoms (particularly zinc atoms); Combination (C2) = A combination of an imidazole molecule represented by general formula (1) (particularly 2-methylimidazole and / or nitroimidazole) and one or more metal atoms selected from the group consisting of zinc atoms and cobalt atoms (particularly zinc atoms); Combination (C3) = A combination of a benzimidazole molecule represented by general formula (2) and one or more metal atoms selected from the group consisting of zinc atoms and cobalt atoms.

[0053] The ratio of organic molecules to metal atoms in an MOF is not particularly limited, but is usually determined by the types of organic molecules and metal atoms that constitute the MOF. For example, an imidazole molecule (Im) (for example, an imidazole molecule represented by general formula (1)) and one or more divalent metal atoms (M) selected from the group consisting of zinc atoms, cobalt atoms, and iron atoms. 1 MOFs containing only ) have the composition formula: M 1 It can also be represented by (Im)2; for example, a benzimidazole molecule (bIm) (for example, a benzimidazole molecule represented by general formula (2)) and one or more divalent metal atoms (M) selected from the group consisting of zinc atoms, cobalt atoms, and iron atoms. 1 MOFs containing only ) have the composition formula: M 1 It can also be represented by (bIm)2; for example, a triazole molecule (Tra) (for example, a triazole molecule represented by general formula (3) and / or (4)) and one or more divalent metal atoms (M) selected from the group consisting of zinc atoms, cobalt atoms and iron atoms. 1 MOFs containing only ) have the composition formula: M 1It can also be represented by (Tra)2; for example, a purine molecule (Pur) (for example, a triazole molecule represented by general formula (5)) and one or more divalent metal atoms (M) selected from the group consisting of zinc atoms, cobalt atoms, and iron atoms. 1 MOFs containing only ) have the composition formula: M 1 It can also be represented by (Pur)2. For example, an imidazole molecule (Im) (e.g., an imidazole molecule represented by general formula (1)) and a benzimidazole molecule (bIm) (e.g., a benzimidazole molecule represented by general formula (2)) and one or more divalent metal atoms (M) selected from the group consisting of zinc atoms, cobalt atoms and iron atoms. 1 MOFs containing only ) have the composition formula: M 1 (Im) x (bIm) y It can be expressed as (where x + y = 2).

[0054] The pore size of a MOF depends on the types of organic molecules and metal atoms that make up the MOF. Therefore, the pore size can be adjusted by selecting the types of organic molecules and metal atoms.

[0055] The MOF may be, for example, the following MOFs: ZIF-1 (composition formula: Zn(Im)2); ZIF-4 (composition formula: Zn(Im)2); ZIF-7 (composition formula: Zn(bIm)2); ZIF-8 (composition formula: Zn(mIm)2); ZIF-9 (composition formula: Co(bIm)2); ZIF-14 (composition formula: Zn(eIm)2); ZIF-81 (composition formula: Zn(cbIm)(nIm)); ZIF-75 (composition formula: Co(mbIm)(nIm)); ZIF-77 (composition formula: Zn(nIm)2); ZIF-81 (composition formula: Zn(brbIm)(nIm)). Here, the abbreviations in the composition formulas indicate the following compounds. Im: Imidazole, bIm: Benzimidazole, mIm: Methylimidazole, eIm: Ethylimidazole, nIm: Nitroimidazole, cbIm: Chlorobenzimidazole, brbIm: Bromobenzimidazole.

[0056] The BET specific surface area of ​​porous materials is typically 100 m². ２ / g or more 2000m ２The amount is less than or equal to / g, and from the viewpoint of further improving the adsorption rate, it is preferably 800m ２ / g or more 1800m ２ / g or less, more preferably 950m ２ / g or more 1600m ２ / g or less, more preferably 950m ２ / g or more 1500m ２ / g or less, particularly preferably 950m ２ / g or more 1300m ２ It is less than or equal to / g.

[0057] In this specification, the BET specific surface area of ​​porous materials is the value obtained by the same method as the method for measuring the BET specific surface area of ​​carbon dioxide adsorbing materials.

[0058] The average primary particle diameter of porous materials is typically 0.01 μm to 10 μm, and from the viewpoint of further improving the adsorption rate, it is preferably 0.01 μm to 5 μm, more preferably 0.01 μm to 3 μm, and even more preferably 0.02 μm to 0.2 μm.

[0059] In this specification, the average primary particle diameter is calculated by approximating the diameters obtained by circular approximation for any 50 support particles in the SEM image, representing them as a pore distribution, and using the median value.

[0060] The average pore diameter of porous materials is typically 0.1 nm to 30 nm, and from the viewpoint of further improving the adsorption rate, it is preferably 0.2 nm to 20 nm, more preferably 0.2 nm to 10 nm, even more preferably 0.3 nm to 8 nm, and very preferably 1 nm to 5 nm.

[0061] In this specification, the average pore diameter of porous materials is the value obtained by the same method as the method for measuring the average pore diameter of carbon dioxide adsorbing materials.

[0062] The total pore volume of porous materials is typically 0.01 cm³. ３ / g or more 10cm ３ It is less than or equal to / g, and from the viewpoint of further improving the adsorption rate, it is preferably 0.1 cm. ３ / g or more 8cm ３ less than or equal to 0.2 cm / g, more preferably 0.2 cm３ 6 cm or more per g ３ 4 cm or less per g, more preferably 0.4 cm ３ 5 cm or more per g ３ 1 cm or less per g, highly preferably 1 cm ３ 4 cm or more per g ３ It is 4 cm or less per g.

[0063] In this specification, the total pore volume of the porous material uses the value measured by the same method as the measurement method of the total pore volume of the carbon dioxide adsorbent material.

[0064] The amine compound is not particularly limited as long as it is a substance having an amino group, and usually an amino group-containing organic compound is used. The weight average molecular weight of the amino group-containing organic substance is not particularly limited, and may be, for example, 100 or more. The weight average molecular weight of the amino group-containing organic substance is 300 or more, preferably 500 or more, from the viewpoint of preventing a decrease in the adsorption ability of carbon dioxide gas due to volatilization. The upper limit value of the weight average molecular weight is not particularly limited, and the weight average molecular weight may usually be 10,000 or less, particularly 1,000 or less. Specific examples of the amino group-containing polymer include, for example, polyethyleneimine (PEI), polyamidoamine, polyvinylamine, and the like. The amino group-containing polymer may be linear or branched, and is preferably branched from the viewpoint of further improving the adsorption ability of carbon dioxide gas.

[0065] From the viewpoint of further improving the adsorption rate, the amine compound is preferably polyethyleneimine, particularly branched polyethyleneimine.

[0066] The amine value of the amine compound (particularly the amino group-containing polymer) is not particularly limited, and is usually 15 to 25 mmol / g·solid, and preferably 17 to 22 mmol / g·solid from the viewpoint of further improving the adsorption rate.

[0067] The amine value uses the value measured by the neutralization method calculated from the amount of hydrochloric acid required to neutralize the amine compound.

[0068] In the carbon dioxide adsorption material of the present invention, the content of the amine compound is usually 10 parts by mass or more and 300 parts by mass or less per 100 parts by mass of porous material, and from the viewpoint of further improving the adsorption rate, it is preferably 30 parts by mass or more and 300 parts by mass or less, more preferably 30 parts by mass or more and 230 parts by mass or less, even more preferably 50 parts by mass or more and 220 parts by mass or less, and very preferably 100 parts by mass or more and 220 parts by mass or less.

[0069] The amine compound content can be measured and calculated from the mass of the carbon dioxide adsorbent material before and after the removal of the amine compound. The removal of the amine compound can be easily achieved by washing the carbon dioxide adsorbent material with an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the amine compound, and examples include ethanol, methanol, and chloroform.

[0070] In the carbon dioxide adsorption material of the present invention, the pore diameter of the pore diameter distribution peak is typically 0.05 nm to 5 nm smaller than the pore diameter of the pore diameter distribution peak of a porous material that does not contain an amine compound. Specifically, the pore diameter of the pore diameter distribution peak of the carbon dioxide adsorption material is r Ａ And the pore size of the pore size distribution peak of a porous material that does not contain amine compounds is set to r. Ｂ When that is the case, "r Ｂ -r Ａ The value represented by is 0.05 nm or more and 5 nm or less, and from the viewpoint of further improving the adsorption rate, it is preferably 0.08 nm or more and 4 nm or less, more preferably 0.5 nm or more and 4 nm or less, and even more preferably 1 nm or more and 4 nm or less. The pore size of the pore size distribution peak of the porous material that does not contain the amine compound may be the pore size of the pore size distribution peak of the porous material after the amine compound has been removed from the carbon dioxide adsorption material. The pore size distribution peak is the maximum peak in the pore size distribution.

[0071] The carbon dioxide adsorbent material of the present invention can be manufactured by the following method: an organic solvent solution of an amine compound is added to a porous material, mixed, and then heat-treated to remove the organic solvent.

[0072] The organic solvent is not particularly limited as long as it can dissolve the amine compound, and examples include ethanol, methanol, and chloroform. If water is used instead of the organic solvent, even if the amine compound dissolves in the water, the amine compound cannot be sufficiently encapsulated in the pores due to the surface tension of water, etc., so the average pore diameter of the carbon dioxide adsorbent material does not increase, and the carbon dioxide adsorbent material of the present invention cannot be obtained.

[0073] The concentration of the amine compound in the organic solvent solution is usually between 10% and 30% by volume, and preferably between 15% and 25% by volume from the viewpoint of further improving the adsorption rate. In particular, if the amine compound is PEI with an average molecular weight of 600, if the above concentration is too high, the pore diameter and / or pore capacity of the resulting carbon dioxide adsorption material will decrease, and the carbon dioxide adsorption material of the present invention cannot be obtained.

[0074] The amount of amine compound used, y (ml / g), is calculated by multiplying the total pore volume of the porous material by x (cm²). ３ When expressed as ( / g), as shown in Figure 5, the value is within ±0.2436 ml / g, with y = 1.131x + 0.0393 as the reference. For details, the amount of amine compound used (or supplied) is determined by the total pore capacity of the porous material (BET) of x (cm ３When expressed as ( / g), the amount is within the range of "1.131 × x - 0.2043" ml / g or more and "1.131 × x + 0.2829" ml / g or less. The amount of amine compound used (or supplied) refers to the amount of the amine compound added individually, and may be, for example, the amount of the amine compound used (or supplied) calculated from the amount added to the solution when used as a 200 mg / mL concentration solution. If the amount of amine compound used is too high, the pore diameter and / or pore capacity of the resulting carbon dioxide adsorption material will decrease, and the carbon dioxide adsorption material of the present invention cannot be obtained. If the amount of amine compound used is too low, the absolute amount of amino groups, which are carbon dioxide adsorption sites, will decrease, and the carbon dioxide adsorption material of the present invention cannot be obtained. Figure 5 is a graph of the total pore capacity of the porous material BET - optimal PEI addition amount, showing the optimal PEI addition amount when producing the carbon dioxide adsorption material of the present invention.

[0075] The heat treatment should be carried out under relatively mild conditions. This is thought to slow down the degassing rate of the solvent, allowing the amine compound solution to diffuse deep into the pores in a low viscosity state, and resulting in the amine compound being uniformly encapsulated within the pores. For example, since pure PEI has very high viscosity, it is easier for it to diffuse into the pores when it is diffused with the solvent present. The heating temperature should be between 40°C and 65°C, preferably between 50°C and 65°C, and more preferably between 55°C and 65°C, from the viewpoint of further improving the adsorption rate. The heating time should be between 20 minutes and 120 minutes, preferably between 40 minutes and 100 minutes, and more preferably between 50 minutes and 70 minutes, from the viewpoint of further improving the adsorption rate. If the heat treatment is carried out under harsh conditions (strong conditions), the amine compound solution will not diffuse deep into the pores, resulting in a decrease in the pore diameter and / or pore capacity of the resulting carbon dioxide adsorption material, and it will not be possible to obtain the carbon dioxide adsorption material of the present invention.

[0076] (Applications) The carbon dioxide adsorption material of the present invention can be regenerated at relatively low temperatures (60°C and above) and has a fast carbon dioxide adsorption rate. Therefore, it is envisioned for use in DAC (Direct Air Capture), which selectively recovers carbon dioxide from environments with low carbon dioxide concentrations (especially the atmosphere).

[0077] The present invention as described above includes the following preferred embodiments. <1> A carbon dioxide adsorption material in which an amine compound is encapsulated in pores of a porous material, wherein the carbon dioxide adsorption material has a peak pore diameter of 0.4 nm or more and less than 10 nm, a peak pore volume of 0.003 cm ３ / g / nm or more, and an average pore diameter of 1 nm or more and 30 nm or less. <2> The carbon dioxide adsorption material according to <1>, wherein the peak pore diameter of the pore size distribution peak of the carbon dioxide adsorption material is 0.05 nm or more and 5 nm or less smaller than the peak pore diameter of the pore size distribution peak of the porous material that does not encapsulate the amine compound. <3> The carbon dioxide adsorption material according to <1> or <2>, wherein the content of the amine compound in the carbon dioxide adsorption material is 10 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the porous material that does not encapsulate the amine compound. <4> The carbon dioxide adsorption material according to any one of <1> to <3>, wherein the porous material has an average primary particle diameter of 0.01 μm or more and 10 μm or less. <5> The carbon dioxide adsorption material according to any one of <1> to <4>, wherein the amine compound is an amino group-containing polymer having a weight average molecular weight of 100 or more. <6> The carbon dioxide adsorption material according to any one of <1> to <5>, wherein the amine compound is polyethyleneimine. <7> A method for producing a carbon dioxide adsorption material, comprising adding an organic solvent solution of an amine compound to a porous material, mixing, and then performing a heat treatment to degas the organic solvent. <8> The method for producing a carbon dioxide adsorption material according to <7>, wherein the heat treatment is performed by heating at 40°C or more and 65°C or less over 20 minutes or more and 120 minutes or less. <9> When the BET total pore volume of the porous material is x (cm ３ / g), the amount of the amine compound used is "1.131×x - 0.2043" ml / g or more and "1.131×x + 0.2829" ml / g or less. <10> A method for producing a carbon dioxide adsorption material according to any one of <7> to <9> for producing the carbon dioxide adsorption material according to any one of <1> to <6>.

[0078] The present invention will be described in more detail below based on specific examples, but the present invention is not limited in any way to the following examples.

[0079] <Porous Materials> Porous materials having the physical properties shown in Table 1 were used.

[0080]

[0081] <Experimental Example A> A carbon dioxide adsorption material (Comparative Example A1) was produced by filling a porous material "ZIF-8" with polyamine, and a carbon dioxide adsorption material (Example A1) was produced by encapsulating polyamine while leaving pores intact. The pore size distribution and initial (30 minutes) CO2 adsorption of these materials were investigated. ２ The amount of adsorption was measured and is shown in Figures 6 and 7. Further details are as follows.

[0082] (Example A1) As the porous material, ZIF-8 (Basolite Z1200, manufactured by BASF (sigmaaldrich.com), BET specific surface area (1395 m)) was used. ２ 300 mg of ( / g) was prepared. Then, an ethanol solution containing 20 vol% polyamine (polyethyleneimine (PEI), average molecular weight = 600, amine value = 20 mmol / g・solid, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added to the porous material. The amount of PEI solution (20 vol%) added was 2.83 ml per gram of porous material (net amount of PEI added was 0.57 ml per gram of porous material). After mixing at atmospheric pressure for 10 minutes at 25°C, a carbon dioxide adsorbent material was obtained by heating and degassing at 60°C for 60 minutes.

[0083] (Comparative Example A1) A carbon dioxide adsorbent material was obtained by the same method as in Example A1, except that the amount of PEI solution (20 vol%) added was 4.67 ml per gram of porous material (net PEI added amount was 0.93 ml per gram of porous material).

[0084] (Pore size distribution) The distribution was measured using a gas adsorption analyzer (Microtrac Bel, Belsorp Max X). Specifically, the sample (e.g., carbon dioxide adsorption material) was pretreated by heating and degassing it at 120°C under an atmospheric environment for 24 hours, and then holding it at 120°C under vacuum for 15 hours. The HK method and BJH method were applied to the obtained nitrogen adsorption isotherm to measure the pore size distribution, which is shown in Figure 6. In subsequent experimental examples, when this measurement method is applied mutatis mutandis to a sample without polyamine encapsulation, the pore size distribution was measured in the same manner as above, except that the pretreatment was performed by holding it at 150°C under vacuum for 15 hours.

[0085] (CO2 over 30 minutes) ２ Adsorption amount) The manufactured wet powdered carbon dioxide adsorption material is placed in a 12L capacity acrylic chamber, CO ２ Introducing 24 ml of gas, CO ２ The concentration was monitored, and the graph shown in Figure 7 was created. The conditions inside the acrylic chamber were atmospheric pressure, 25°C, and approximately 50% humidity.

[0086] Figure 7 shows the initial (30 minutes) CO2 levels in Example A1. ２ The amount of adsorption was the initial (30 minutes) CO2 in Comparative Example A1. ２ The amount of adsorption increased by approximately 1.4 times compared to the initial CO ２ When it is desired to increase the adsorption amount, it is clearly better to leave the pores unfilled, as in the present invention, rather than filling them, as in Patent Document 2. CO2 with the characteristics of the present invention ２ When using adsorbent materials, the initial CO ２ The amount of adsorption can be improved.

[0087] <Experimental Example B> (Examples B1 and B2 and Comparative Examples B1-B3) CO2 when the amount of polyamine encapsulated in the following materials as porous or non-porous materials is varied. ２ The amount of adsorption is shown in Figure 8. • ZIF-8 (porous material, BET specific surface area 1395 m²) ２ / g, Basolite Z1200, manufactured by BASF (sigmaaldrich.com) ・HS-320 (porous material, BET specific surface area 904 m²) ２ / g, Fujifilm Wako Chemical Co., Ltd., CAS RN 308081-05-2, Synthetic zeolite, Zeolite, Powder, Sodium Y) ・MCM-41 (Porous material, BET specific surface area 1022 m²) ２ / g, mesoporous silica, manufactured by Sigma-Aldrich, mesostructure, type (hexagonal)) ・DE (porous material, BET specific surface area 116 m²) ２ / g, diatomaceous earth (from Wakkanai), Natural Materials Research Institute Co., Ltd.) ・Al ２ O ３ (Non-porous material, BET specific surface area 8m ２ ( / g, manufactured by Sumitomo Chemical Co., Ltd.)

[0088] In detail, a carbon dioxide adsorption material was obtained by the same method as in Example A1, except that the above-mentioned porous or non-porous material was used and the supply amount of PEI solution (20 vol%) was set to a predetermined value. Then, the CO2 adsorption material was used and the adsorption time was set to 60 minutes, except that the CO2 adsorption material was used in the same manner as in Experimental Example A. ２ CO ２ The amount of adsorption was measured. This involved the amount of PEI solution supplied and the CO2 adsorption rate over 60 minutes. ２ Figure 8 was created based on the relationship with the amount of adsorption. Comparative Example A1 is also shown in Figure 8. The samples indicated by the arrows in Figure 8 were used as Examples B1 and B2 and Comparative Examples B1, B2, and B3, and the pore size distribution was measured using the same method as the pore size distribution measurement method for Experimental Example A, and is shown in Figures 9A and 9B.

[0089] As shown in Figures 8, 9A, and 9B, the carbon dioxide adsorption materials of Examples B1 and B2, which have the features of the present invention, adsorb up to approximately 5.3 times more CO2 per gram of porous material compared to the carbon dioxide adsorption materials of Comparative Examples B1, B2, and B3. ２The amount of adsorption is shown. Note that Example B2 corresponds to Example A1. In particular, Figure 9B clearly shows the difference between Example B1 and Comparative Example B3. From Figure 9B, it can be seen that the peak of pore capacity in Comparative Example B3 is at 10 nm. Also, from Figure 8, the amount of CO2 adsorbed in Comparative Example B3 is significantly smaller than that of Example B1. This indicates that the 10 nm pores do not contribute to CO2 adsorption.

[0090] <Experimental Example C> The carbon dioxide adsorption materials of Examples B1 and B2, produced in Experimental Example B, were thoroughly washed with ethanol to remove amine compounds (especially polyamines) from the carbon dioxide adsorption materials. The pore size distribution of the obtained porous material ("porous material only") was measured using the same method as the pore size distribution measurement method in Experimental Example A. The pore size distribution before and after the removal of amine compounds for Examples B1 and B2 are shown in Figures 10 and 11, respectively. In Figure 10, the peak of the pore size distribution showed a shift of 3 nm. In Figure 11, the peak of the pore size distribution showed a shift of 0.25 nm. The shift amount is calculated by moving the pore size of the pore size distribution peak of the carbon dioxide adsorption material to r. Ａ Furthermore, the pore size of the pore size distribution peak of the porous material from which the amine compound has been removed is set to r. Ｂ When that is the case, "r Ｂ -r Ａ This refers to the value represented by "".

[0091] The peak shift in the pore distribution represents the decrease in pore diameter and is thought to correspond to twice the thickness of the polyamine in the pores.

[0092] <Experimental Example D>

[0093] (Comparative Example D1) A carbon dioxide adsorbent material was obtained in the same manner as in Example A1, except that water was used instead of ethanol as the solvent for the polyamine solution. Then, the carbon dioxide adsorbent material produced in Comparative Example D1 was used, and the adsorption time was set to 60 minutes, except that the CO2 adsorbent material produced in Comparative Example D1 was used, and the CO2 adsorbent material was set to 60 minutes. ２ CO ２ The amount of adsorption was measured and is shown in Figure 12. The carbon dioxide adsorption material produced in Example A1 also showed CO２ The amount of adsorption was measured and is shown in Figure 12. Figure 12 is a graph showing the elapsed time and carbon dioxide adsorption amount, illustrating an example of the amount of carbon dioxide adsorbed during the initial period (60 minutes) of adsorption for the carbon dioxide adsorption materials in Example A1 and Comparative Example D1.

[0094] <Characteristic Values> The characteristic values ​​of the carbon dioxide adsorption materials for Examples A1 (B2) and B1, and Comparative Examples A1, B1, B2, B3 and D1 are shown below.

[0095]

[0096] A comparison of the values ​​for ZIF-8 and MCM-41 in Table 1 with the values ​​for Examples A1 and B1 in Table 2 shows that the average pore diameter of the porous material is larger than that of the carbon dioxide adsorbent material containing amine compounds. This is thought to be due to the following reason: When PEI is added to the porous material, the majority of small pores (e.g., pores smaller than 1 nm) are filled with PEI, and these small pores are not counted, while only larger pores (e.g., pores larger than 1 nm) are counted. Therefore, the average pore diameter of the porous material appears to be larger than that of the carbon dioxide adsorbent material.

[0097] A comparison of the values ​​for ZIF-8 and MCM-41 in Table 1 with the values ​​for Examples A1 and B1 in Table 2 shows that the total pore capacity of the porous material is larger than that of the carbon dioxide adsorbent material containing the amine compound. This is thought to be due to the following reason: When PEI is added to the porous material, the pores of the porous material are filled with PEI, so the total pore capacity of the porous material is considered to be larger than that of the carbon dioxide adsorbent material.

[0098] (CO2 over 60 minutes) ２ Adsorption amount) CO2 in 60 minutes ２ Aside from measuring the amount of adsorption, the aforementioned "CO2 in 30 minutes" ２ The amount of adsorption was measured using the same method as described above.

[0099] (Optimal PEI supply amount) In Figure 8, the maximum "CO2 supply over 60 minutes" ２The amount of PEI solution supplied that achieved the desired adsorption amount was defined as the "optimal PEI supply amount."

[0100] (BET specific surface area) The BET specific surface area of ​​the support material (porous or non-porous material) containing the polyamine was measured using Belsorp Max X (Microtrac-Bel). The measurement conditions were as follows: - Heating and degassing at 120°C and in an atmospheric environment for 24 hours; - Pretreatment by holding at 150°C and in a vacuum for 15 hours; - Measurement of nitrogen adsorption isotherms between relative pressures of 1.0E-8 and 0.99; - The BET method was applied to the obtained nitrogen adsorption isotherms.

[0101] Furthermore, the BET specific surface area of ​​a wet, powdery carbon dioxide adsorbent material containing polyamine was measured using a Belsorp Max X (Microtrac-Bel). The measurement conditions were as follows: - Heat treatment at 120°C in an atmospheric environment for 24 hours; - Pretreatment at 120°C in a vacuum for 15 hours (by holding); - Measurement of nitrogen adsorption isotherms between relative pressures of 1.0E-8 and 0.99; - Application of the BET method to the obtained nitrogen adsorption isotherms.

[0102] (Pore Capacity) The pore size distribution was measured and the BET total pore capacity was determined using the same method as described above for measuring the pore size distribution. In particular, the BET total pore capacity was calculated using a value of 0.99 relative pressure.

[0103] (Average pore diameter) The pore diameter distribution was measured using the same method as described above, and the average pore diameter for all pores was determined.

[0104] (Average primary particle diameter) The average primary particle diameter is calculated by approximating the diameters of 50 arbitrary support particles (porous or non-porous material) in the SEM image using a circular approximation, representing the pore distribution, and using the median value.

[0105] The carbon dioxide adsorption material of the present invention is useful for sensors (especially carbon dioxide sensors), carbon dioxide gas adsorption filters, and carbon dioxide gas removal devices.

[0106] 1: Carbon dioxide adsorbent material 2: Porous material 3: Amine compound 10: Carbon dioxide 30: Region of the amine compound that can come into contact with carbon dioxide

Claims

1. A carbon dioxide adsorption material comprising an amine compound encapsulated within the pores of a porous material, wherein the carbon dioxide adsorption material has a peak pore diameter of 0.4 nm or more and less than 10 nm, and 0.003 cm². ３ A carbon dioxide adsorption material having a peak pore capacity of 1 nm to 30 nm and a peak pore capacity of 1 nm to 30 nm.

2. The carbon dioxide adsorbent material according to claim 1, wherein the peak pore diameter of the pore diameter distribution peak of the carbon dioxide adsorbent material is 0.05 nm to 5 nm smaller than the peak pore diameter of the pore diameter distribution peak of the porous material that does not contain the amine compound.

3. The carbon dioxide adsorbent material according to claim 1 or 2, wherein the content of the amine compound in the carbon dioxide adsorbent material is 10 parts by mass or more and 300 parts by mass or less per 100 parts by mass of the porous material that does not contain the amine compound.

4. The carbon dioxide adsorption material according to any one of claims 1 to 3, wherein the porous material has an average primary particle diameter of 0.01 μm or more and 10 μm or less.

5. The carbon dioxide adsorption material according to any one of claims 1 to 4, wherein the amine compound is an amino group-containing polymer with a weight-average molecular weight of 100 or more.

6. The carbon dioxide adsorption material according to any one of claims 1 to 5, wherein the amine compound is polyethyleneimine.

7. A method for producing a carbon dioxide adsorbent material, comprising adding an organic solvent solution of an amine compound to a porous material, mixing it, and then heat-treating it to degas the organic solvent.

8. The method for producing a carbon dioxide adsorption material according to claim 7, wherein the heat treatment is performed by heating at a temperature of 40°C to 65°C for 20 minutes to 120 minutes.

9. The amount of the amine compound used is calculated by multiplying the total pore capacity of the porous material (relative pressure 0.99) by x (cm²). ３ A method for producing a carbon dioxide adsorption material according to claim 7 or 8, wherein the amount is "1.131 × x - 0.2043" ml / g or more and "1.131 × x + 0.2829" ml / g or less, when expressed as ( / g).

10. A method for producing a carbon dioxide adsorption material according to any one of claims 7 to 9, comprising producing a carbon dioxide adsorption material according to any one of claims 1 to 6.

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