Carbon dioxide collector

Abstract

To provide a carbon dioxide collector which can efficiently recover carbon dioxide, even if the carbon dioxide collector is arranged in a comparatively small space such as general home.SOLUTION: A carbon dioxide collector 1 includes an absorption part 2 for absorbing carbon dioxide, in which the absorption part 2 has a hydrophobic part 21 exhibiting hydrophobic property and a hydrophilic part 22 exhibiting hydrophilic property more than the hydrophobic part 21, the hydrophobic part 21 contains an absorber chemically reactive with carbon dioxide such as amine, the absorber has property to be ionized by reaction with carbon dioxide, the hydrophobic part 21 and the hydrophilic part 22 are arranged so as to enable ion exchange, a filter part 3 having property to prevent permeation of an absorber is arranged between the absorption part 2 and air, and the absorption part 2 is arranged so as to be brought into contact with air through only the filter part 3.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a carbon dioxide collector that captures carbon dioxide in the air. [Background technology]

[0002] In recent years, technological developments have been made to capture and effectively utilize carbon dioxide, a representative greenhouse gas. In particular, there is a strong demand for reducing carbon dioxide emissions from thermal power plants, steel plants, chemical plants, and other plants that emit large amounts of carbon dioxide.

[0003] An example of a carbon dioxide capture technology that has been put to practical use is the chemical absorption method in which carbon dioxide is absorbed in an absorbing solution containing an alkaline compound (see Patent Document 1). Patent Document 1 describes a carbon dioxide separation and capture system that can cause the absorbing solution, which separates into two layers by reacting with carbon dioxide, to be refluxed to the absorption tower with a balanced alkaline compound and water content, thereby allowing the absorbing solution to sufficiently absorb carbon dioxide. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication 2018-134604 Summary of the Invention [Problem to be solved by the invention]

[0005] From the viewpoint of reducing greenhouse gases, it is desirable to be able to capture carbon dioxide not only in thermal power plants and steel plants, but also in ordinary homes. However, since thermal power plants and steel plants can have large-sized facilities, it is possible to provide equipment for stirring as described in Patent Document 1. However, since it is required to capture carbon dioxide in a relatively small space in ordinary homes, it is difficult to provide equipment for stirring. In other words, if an attempt is made to capture carbon dioxide in the air in ordinary homes using the chemical absorption method described in Patent Document 1, there is a concern that the reacted absorbing solution will be unevenly distributed near the air inlet, resulting in a deterioration in capture efficiency.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a carbon dioxide collector that can efficiently capture carbon dioxide even when placed in a relatively small space such as an ordinary home. [Means for solving the problem]

[0007] The present invention is characterized in that it is a carbon dioxide collector which comprises an absorption section that absorbs carbon dioxide, the absorption section having a hydrophobic section that exhibits hydrophobicity and a hydrophilic section that exhibits more hydrophilicity than the hydrophobic section, the hydrophobic section and the hydrophilic section being formed of a porous body, the porous body forming the hydrophobic section including an absorbent that reacts with carbon dioxide and is ionized, and the hydrophobic section and the hydrophilic section being formed integrally or arranged in contact with each other.

[0008] That is, the carbon dioxide collector of the present invention has a hydrophobic part that exhibits hydrophobicity and a hydrophilic part that exhibits hydrophilicity more than the hydrophobic part, and is configured such that the hydrophobic part and the hydrophilic part are formed of a porous body and are formed integrally or are arranged in contact with each other. With such a configuration, the absorbent that has been ionized by reacting with carbon dioxide can be moved to the hydrophilic part. Therefore, without providing special equipment, the hydrophobic part can be made to contain a large amount of absorbent before the reaction, and a large amount of carbon dioxide can be captured by the hydrophobic part (the absorption part having the hydrophobic part). That is, even if the carbon dioxide collector is placed in a relatively small space such as an ordinary home, it can efficiently capture (recover) carbon dioxide. Furthermore, since each phase is formed of a porous body rather than a liquid, it is possible to reduce the risk of the absorbent leaking to the outside of the carbon dioxide collector. In addition, when recovering carbon dioxide from the carbon dioxide collector or performing maintenance, it is possible to perform the simple operation of removing the hydrophilic part, which is a porous body, from the inside, compared to when the hydrophilic part is in a liquid phase, and it is possible to provide a carbon dioxide collector that is easy to handle.

[0009] In addition, a filter section may be provided between the absorption section and the air, the filter section having a property of not allowing the absorbent to pass to the outside, and the filter section and the absorption section may be arranged so that the absorption section comes into contact with the air only via the filter section. With such a configuration, it is possible to prevent the absorbent, which is harmful to the human body, from leaking out. In other words, the carbon dioxide collector can be suitable for use in ordinary households, etc.

[0010] The filter portion may be provided between the hydrophobic portion and the air. In this configuration, the hydrophobic portion and the air can be in contact with each other, and a larger amount of carbon dioxide can be captured.

[0011] The hydrophobic portion may be configured to cover the outer peripheral side surface of the hydrophilic portion, and the hydrophobic portion may be configured to have a cylindrical shape. With such a configuration, the contact area between the hydrophobic portion and the air can be increased, and a larger amount of carbon dioxide can be captured. Effect of the Invention

[0012] According to the present invention, it is possible to provide a carbon dioxide collector that can efficiently capture carbon dioxide even when placed in a relatively small space such as an ordinary home. [Brief description of the drawings]

[0013] [Figure 1] 1 is a perspective view of a carbon dioxide collector according to a first embodiment of the present invention. [Diagram 2] 1 is a vertical cross-sectional view of a carbon dioxide collector according to a first embodiment of the present invention. [Diagram 3] 1 is a cross-sectional view of a carbon dioxide collector according to a first embodiment of the present invention. [Figure 4] Equation showing the reaction of amines with carbon dioxide. [Diagram 5] FIG. 4 is a perspective view of a carbon dioxide collector according to a second embodiment of the present invention. [Figure 6] FIG. 4 is a vertical cross-sectional view of a carbon dioxide collector according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0015] <First embodiment> FIG. 1 is a perspective view of a carbon dioxide collector 1 according to a first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of the carbon dioxide collector 1 according to the first embodiment of the present invention, and FIG. 3 is a horizontal cross-sectional view of the carbon dioxide collector 1 according to the first embodiment of the present invention. In this specification, the upper side, bottom side, and side surfaces are described with the upper side in FIG. 2 being the top side of the carbon dioxide collector 1 and the lower side being the bottom side of the carbon dioxide collector 1.

[0016] The carbon dioxide collector 1 in this embodiment has a cylindrical shape and includes an absorption section 2 that absorbs carbon dioxide, a filter section 3 disposed opposite the outer surface of the absorption section 2, and a fixing section 4 that fixes the absorption section 2 and the filter section 3 by sandwiching them from the top and bottom. The size of the carbon dioxide collector 1 is large enough to be placed at least partially indoors in an average home.

[0017] The absorbing section 2 has a hydrophobic section 21 having hydrophobic properties and a hydrophilic section 22 exhibiting more hydrophilicity than the hydrophobic section 21. The hydrophobic section 21 and the hydrophilic section 22 are formed of a porous body. In this embodiment, the hydrophilic section 22 is provided in a cylindrical range in the center of the carbon dioxide collector 1, and the inner circumferential surface of the hydrophobic section 21 is disposed in close contact with the outer circumferential surface of the hydrophilic section 22. That is, the absorbing section 2 is disposed in layers from the center of the carbon dioxide collector 1 in the order of the hydrophilic section 22 and the hydrophobic section 21. In this embodiment, the central axis of the hydrophilic section 22 overlaps with the central axis of the carbon dioxide collector 1. Furthermore, the hydrophobic section 21 has a cylindrical region, and the central axis overlaps with the central axis of the carbon dioxide collector 1.

[0018] The hydrophobic portion 21 is formed of a porous body having a countless number of fine holes inside. For example, a sponge, a porous ceramic, or a porous resin can be used as such a porous body. The hydrophobic portion 21 also includes an absorbent that chemically reacts with carbon dioxide and ionizes. For example, an amine can be used as such an absorbent. For example, the amine that can be used as the absorbent can be one or a mixture of low molecular weight amines such as monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1-propanol, 2-isopropylaminoethanol, 2-(methylamino)ethanol, 2-(ethylamino)ethanol, N-methyldiethanolamine, ethylenediamine, hexamethylenediamine, diethylenetriamine, piperazine, o-xylylenediamine, m-xylylenediamine, p-xylylenediamine, and isophoronediamine. Alternatively, a polymeric amine such as polyethyleneimine can be used. It is preferable to use a sponge as the porous body. It is preferable to use an amine as the absorbent, and it is more preferable to use a polymeric amine.

[0019] The hydrophobic portion 21 can be prepared by dissolving the absorbent in an organic solvent to prepare an absorbing liquid, and impregnating the porous body with the absorbing liquid for a predetermined time. As the organic solvent for dissolving the absorbent, an organic solvent that can dissolve the absorbent and has a boiling point that does not volatilize when heated to desorb (recover) carbon dioxide from the absorbent can be used. For example, when the absorbent is an amine, it is necessary to heat the absorbent to 80°C or higher when desorbing carbon dioxide from the amine. Therefore, an organic solvent that can dissolve the amine and has a boiling point of 80°C or higher, preferably 120°C or higher, can be used. For example, xylene, toluene, butyl acetate, etc. can be used as such an organic solvent. In addition, it is more preferable to use an organic solvent with low volatility. For example, a liquid olefin can be used as such an organic solvent with low volatility.

[0020] In addition, at this time, it is preferable to coat the porous body with a hydrophobic resin and perform a treatment (hydrophobicity imparting treatment) in advance to impart hydrophobicity. For example, epoxy, polyethylene, polypropylene, polytetrafluoroethylene, etc. can be used as the resin for imparting hydrophobicity. Alternatively, the porous body itself may be formed of a hydrophobic material. For example, a method for coating the porous body with a hydrophobic resin is to dilute a two-component resin before curing with a volatile organic solvent such as xylene, add a curing agent, and stir to prepare a coating liquid. Thereafter, a method can be used in which the porous body is impregnated with the coating liquid before the coating liquid is cured, and the porous body is heated to remove the organic solvent and harden the resin.

[0021] The hydrophilic portion 22 is formed of a porous body having numerous fine holes therein. For example, a sponge, a porous ceramic, or a porous resin can be used as such a porous body, and it is preferable to use a sponge. The hydrophilic portion 22 is more hydrophilic than the hydrophobic portion 21. It is preferable that the hydrophilic portion 22 is hydrophilic. It is preferable that the volume of the hydrophilic portion 22 is larger than the volume of the hydrophobic portion 21.

[0022] The hydrophilic portion 22 can be prepared, for example, by impregnating a porous body with water, an amine solution in which an amine is dissolved in water, or water containing carbamate anions for a predetermined time. Alternatively, the surface in contact with the hydrophobic portion 21 may be oxidized by ultraviolet light to increase the hydrophilicity of the surface, and the hydrophilic portion 22 may be a porous body. Furthermore, since the hydrophobic portion 21 exhibits hydrophobicity, a porous body that is not particularly treated and does not contain water or the like can be used as the hydrophilic portion 22. In other words, the state or treatment of the hydrophilic portion 22 is not particularly limited as long as the hydrophilic portion 22 exhibits hydrophilicity (low hydrophobicity, low lipophilicity) more than the hydrophobic portion 21.

[0023] The hydrophilic portion 22 and the hydrophobic portion 21 are arranged so as to be in close contact with each other. In addition, it is preferable that the hydrophilic portion 22 and the hydrophobic portion 21 have uneven surfaces that face each other (are in close contact with each other), and the convex shape of one portion is engaged with the concave shape of the other portion.

[0024] In this embodiment, separate porous bodies are used for the hydrophilic portion 22 and the hydrophobic portion 21, but phases corresponding to the hydrophilic portion 22 and the hydrophobic portion 21 may be created in one porous body. More specifically, a hydrophobic treatment is applied only to the vicinity of the outer peripheral surface of one porous body, and no particular treatment is applied to the other portion (near the center). With one porous body that has been treated in this way, the vicinity of the outer peripheral surface is the most hydrophobic (state of the hydrophobic portion 21), and the hydrophobicity decreases toward the center (state of the hydrophilic portion 22), and the same effect as in the above-mentioned embodiment can be obtained.

[0025] The filter section 3 has a property of being permeable to at least carbon dioxide in the air and impermeable to the absorbent. The filter section 3 is formed in a cylindrical shape and arranged so as to cover the outer peripheral side surface of the hydrophobic section 21 (absorption section 2). Furthermore, the filter section 3 forms the outer peripheral side surface of the carbon dioxide collector 1. The filter section 3 in this embodiment is arranged opposite the hydrophobic section 21 (absorption section 2) and is composed of a film-like absorber filter 31 that is impermeable to the absorber, and a holder 32 to which the absorber filter 31 is attached on the inner peripheral surface and which holds the absorber filter 31.

[0026] The holder 32 has a cylindrical shape, and the film-like absorber filter 31 is attached (provided) so as to cover the entire inner peripheral surface thereof. The holder 32 has a property of at least transmitting carbon dioxide in the air. The holder 32 has a hardness and thickness such that the attached absorber filter 31 does not deform. For example, a porous ceramic made of aluminum oxide or a metal mesh can be used as the holder 32. The holder 32 is formed as the outer peripheral side surface of the carbon dioxide collector 1, and is arranged and formed so that the air (outside air, atmosphere) surrounding the carbon dioxide collector 1 comes into contact with the outer peripheral side surface of the holder 32.

[0027] The absorbent filter 31 has a property of being permeable to at least carbon dioxide in the air and impermeable to the absorbent (the absorbing liquid containing the absorbent) contained in the hydrophobic portion 21. As the absorbent filter 31 having such a property, a film-like or sheet-like porous body (porous film or porous sheet) can be used. More specifically, for example, a porous film or a porous sheet made of a porous resin such as polyolefin or polytetrafluoroethylene (PTFE) in a film or sheet shape can be used.

[0028] A zeolite membrane can also be used as the whole or part of the absorber filter 31. The structure of zeolite that can be used as the zeolite membrane is not particularly limited, and zeolites having known structures such as LTA type and CHA type can be used. The zeolite membrane may be formed of the absorber filter 31 itself (formed on the support 32) or may be formed by stacking it on an absorber filter 31 formed of another material (formed on another absorber filter 31).

[0029] The fixing parts 4 are provided on the top and bottom surfaces of the carbon dioxide collector 1, respectively, and fix the absorbing part 2 and the filter part 3 by sandwiching them from the top and bottom surfaces, and have the role of preventing the top and bottom surfaces of the absorbing part 2 from contacting the air, and the role of preventing each liquid contained in the absorbing part 2 and the gas generated in the absorbing part 2 from leaking out of the carbon dioxide collector 1 from the top and bottom surfaces. The fixing parts 4 are formed of a corrosion-resistant material, for example, an alkali-resistant resin material. Examples of such materials that can be used include polyethylene, polypropylene, nylon, polytetrafluoroethylene, tetrafluoroethylene, phenolic resin, and epoxy resin.

[0030] Therefore, the absorbing section 2 is stored inside the carbon dioxide collector 1, which has the filter section 3 and the fixing section 4 as its exterior. Moreover, the absorbing section 2 does not directly contact the air around the carbon dioxide collector 1, but only contacts the gas that has passed through the filter section 3. At this time, in the absorbing section 2, it is the hydrophobic section 21 arranged on the outer periphery that contacts the gas that has passed through the filter section 3, and the hydrophilic section 22, the outer periphery of which is covered by the hydrophobic section 21, does not contact the gas that has passed through the filter section 3. Moreover, the absorber (absorption liquid containing the absorber) contained in the hydrophobic section 21 is prevented from leaking out of the carbon dioxide collector 1 by the filter section 3 (absorber filter 31).

[0031] The carbon dioxide collector 1 having such a configuration can be suitably used by being placed in a room of an ordinary home, etc. Hereinafter, the operation of the carbon dioxide collector 1 of the present invention when placed in a room of an ordinary home will be described.

[0032] The space around the carbon dioxide collector 1 arranged in a room of a general household is usually filled with air containing nitrogen, oxygen, and a small amount of carbon dioxide. The air containing these elements is blown toward the carbon dioxide collector 1 by wind flow or the like. The blown air passes through the filter section 3 (the holder 32 and the absorber filter 31) and comes into contact with the hydrophobic section 21. Note that, in this embodiment, the air is blown into the carbon dioxide collector 1 by wind flow or the like, but the method and environment in which the air is blown into the carbon dioxide collector 1 are not particularly limited. For example, the carbon dioxide collector 1 may be arranged in an environment where air can easily circulate, such as near a window or at a front door, or the air may be forcibly moved in the direction of blowing into the carbon dioxide collector 1 by a blower or the like. Alternatively, even in a windless state without wind flow, a small amount of carbon dioxide contained in the air can be captured.

[0033] FIG. 4 is a reaction formula showing the reaction of an amine with carbon dioxide. At this time, the absorbent contained in the hydrophobic part 21 reacts with the carbon dioxide contained in the air. The absorbent of the present invention has the property of reacting with carbon dioxide and ionizing. Therefore, the absorbent contained in the hydrophobic part 21 reacts with the carbon dioxide contained in the air it comes into contact with and ionizes. For example, when the absorbent is monoethanolamine (RNH2), which is a type of amine, a reaction of reacting with carbon dioxide (CO2) and ionizing it (a reaction from left to right in the reaction formula shown in FIG. 4) proceeds near room temperature in the reaction formula shown in FIG. Therefore, the monoethanolamine (RNH2) contained in the hydrophobic part 21 reacts with the carbon dioxide (CO2) in the air that has been blown in, and an amine conjugate acid (RNH3+) and a carbamate anion (RNHCOO-) are generated.

[0034] An ionized absorbent usually exhibits hydrophilicity as a characteristic of ions. Therefore, the ionized absorbent generated after the reaction in the hydrophobic section 21 naturally moves to the hydrophilic section 22 arranged in close contact with the hydrophobic section 21. That is, a large amount of absorbent (amine before reaction) before reacting with carbon dioxide continues to exist in the hydrophobic section 21 that comes into contact with air.

[0035] The carbon dioxide captured by the carbon dioxide capture body 1 in this manner is released to the outside from the carbon dioxide capture body 1 by heating the carbon dioxide capture body 1 to about 80°C to 120°C in a facility for recovering carbon dioxide. More specifically, in the temperature range of 80°C to 120°C, the reaction proceeds in the direction in which carbon dioxide is generated in the reaction formula shown in FIG. 4 (the reaction proceeds from right to left in the reaction formula shown in FIG. 4). Therefore, when monoethanolamine, which is a type of amine, is used as the absorbent, the amine conjugate acid (RNH3+) and carbamate anion (RNHCOO-) are converted to monoethanolamine (RNH2) while generating carbon dioxide (CO2). The generated carbon dioxide passes through the filter unit 3 and is released to the outside of the carbon dioxide capture body 1.

[0036] After the carbon dioxide has been captured, the carbon dioxide collector 1 is again in a state where a large amount of absorbent (amine) is present in the hydrophobic portion 21. Therefore, the carbon dioxide collector 1 can be placed again in an ordinary home or the like and can once again perform its role of capturing carbon dioxide.

[0037] Moreover, the hydrophobic portion 21 and the hydrophilic portion 22, which are porous bodies, can be easily taken out by removing the fixing portion 4 of the carbon dioxide collector 1. Therefore, if the hydrophobic portion 21 and the hydrophilic portion 22 deteriorate due to long-term use or the like, they can be replaced with new porous bodies (new hydrophobic portion 21 and hydrophilic portion 22) that have been subjected to the corresponding treatment, and can be reused as the carbon dioxide collector 1.

[0038] With the above-described configuration, it is possible to provide a carbon dioxide collector that can efficiently capture carbon dioxide even when placed in a relatively small space such as an ordinary home. The carbon dioxide collector 1 of the present invention has a hydrophobic section 21 that contains an absorbent that reacts with carbon dioxide and ionizes, and is hydrophobic, and a hydrophilic section 22 that is more hydrophilic than the hydrophobic section 21. The hydrophobic section 21 and the hydrophilic section 22 are formed of a porous body, and are either integrally formed or arranged in contact with each other. With this configuration, the absorbent that reacts with carbon dioxide contained in the air and is ionized can be naturally moved from the hydrophobic section 21 to the hydrophilic section 22. Therefore, the hydrophobic section 21 can be kept in a state where the concentration of the absorbent before the reaction is always high. That is, while the absorbent that has reacted would normally be unevenly distributed near the outer periphery of the absorption section 2 (near the area in contact with carbon dioxide) as the carbon dioxide collection continues, the absorbent that has reacted can be moved from the hydrophobic section 21 (outer periphery) that contacts carbon dioxide to the hydrophilic section 22 (interior), and the hydrophobic section 21 can be kept in a state where a large amount of unreacted absorbent is contained. That is, the carbon dioxide collection efficiency in the hydrophobic section 21 can be maintained at a high level, and more carbon dioxide can be collected. Furthermore, with this configuration, no device or equipment is required to stir the absorbent. Therefore, even if the device is placed in a relatively small space such as an ordinary home, it can efficiently capture carbon dioxide.

[0039] Furthermore, it is preferable that the hydrophobic portion 21 and the hydrophilic portion 22 are formed of a sponge. With this configuration, it is possible to reduce the risk of the absorbent leaking to the outside of the carbon dioxide collector 1, compared to when the hydrophobic portion 21 and the hydrophilic portion 22 are in a liquid phase. Furthermore, when recovering carbon dioxide from the carbon dioxide collector 1 or when performing maintenance, compared to when the hydrophilic portion 22 is in a liquid phase, it is possible to perform the operation by simply removing the hydrophilic portion 22, which is a sponge, from the inside, and it is possible to make the carbon dioxide collector 1 easy to handle. Furthermore, compared to other porous bodies such as ceramics, a sponge can contain more absorbent per unit volume. Therefore, it is possible to make the configuration more suitable for use in small spaces where compactness is required.

[0040] The carbon dioxide collector 1 of the present invention includes a filter section 3 between the absorption section 2 and the air, and the filter section 3 has an absorber filter 31 that has a property of not allowing the absorber to pass through. The filter section 3 is arranged so as to cover the outer peripheral side surface of the absorption section 2, and the absorption section 2 is configured to contact only with the air (outside air) that has passed through the filter section 3 (absorber filter 31). In other words, the absorption section 2 is configured to be stored inside the carbon dioxide collector 1. With this configuration, even if the absorber contained in the absorption section 2 is a substance harmful to the human body such as an amine, it is possible to prevent the absorber (the absorbing liquid containing the absorber) from leaking outside the carbon dioxide collector 1. Therefore, the carbon dioxide collector 1 can be suitably used even when it is used in an ordinary home or the like, rather than in a large facility such as a thermal power plant. More specifically, even when the carbon dioxide collector 1 is used in an ordinary home or the like, there is no risk of the absorber (the absorbing liquid containing the absorber) leaking outside the carbon dioxide collector 1, and the carbon dioxide collector 1 can be used safely by the user.

[0041] Furthermore, the carbon dioxide collector 1 of the present invention may have a cylindrical shape, and may be configured so that the hydrophobic portion 21 is disposed so as to cover the outer peripheral side surface of the hydrophilic portion 22. With such a configuration, the contact region (area) between the hydrophobic portion 21 and the air (outside air) can be increased, and a larger amount of carbon dioxide can be captured.

[0042] In the carbon dioxide collector 1 of the present invention, it is preferable that the hydrophilic portion 22 and the hydrophobic portion 21 have surfaces that face each other (are in close contact with each other) with uneven shapes, and the concave shape of one portion meshes with the convex shape of the other portion. With such a configuration, the contact area between the hydrophobic portion 21 and the hydrophilic portion 22 can be increased, and ions generated in the hydrophobic portion 21 can be moved to the hydrophilic portion 22 more efficiently.

[0043] Furthermore, in the carbon dioxide collector 1 of the present invention, an organic solvent having a boiling point of 80° C. or higher is used as the solvent for dissolving the absorbent contained in the hydrophobic section 21, and it is preferable to use an organic solvent having a boiling point of 120° C. or higher. With this configuration, even in a temperature environment of 80° C. where the absorbent proceeds with a reaction to generate (desorb, release) carbon dioxide, the organic solvent does not volatilize, and the carbon dioxide collector 1 after carbon dioxide capture can be reused. Furthermore, if the boiling point of the organic solvent is 120° C. or higher, temperature control during capture can be simplified.

[0044] Furthermore, in the carbon dioxide collector 1 of the present invention, it is preferable to use a low-volatility organic solvent as the solvent for dissolving the absorber contained in the hydrophobic section 21. With such a configuration, the organic solvent is less likely to volatilize. In other words, the organic solvent is less likely to volatilize and be released to the outside of the carbon dioxide collector 1, making it more suitable for use even in general households, etc.

[0045] Moreover, in the carbon dioxide collector 1 of the present invention, it is preferable that the volume of the hydrophilic section 22 is formed to be larger than the volume of the hydrophobic section 21. With such a configuration, it is possible to prevent the ions in the hydrophilic section 22 from becoming saturated and making it difficult for the ions to move from the hydrophobic section 21 to the hydrophilic section 22. In other words, it is possible to prevent a state in which a large amount of reacted amine is present in the hydrophobic section 21, resulting in a decrease in the carbon dioxide absorption efficiency.

[0046] Furthermore, in the carbon dioxide collector 1 of the present invention, it is preferable that the porous body forming the hydrophobic portion 21 is coated with a hydrophobic resin and treated in advance to impart hydrophobicity, or that the porous body forming the hydrophobic portion 21 itself is formed of a hydrophobic material. With this configuration, it is possible to make the hydrophobic portion 21 more hydrophobic than the hydrophilic portion 22 without performing any special treatment on the hydrophilic portion 22 side. In other words, it is possible to make the hydrophilic portion 22 more hydrophilic than the hydrophobic portion 21.

[0047] In the carbon dioxide collector 1 of the present invention, it is preferable that the hydrophilic portion 22 has hydrophilicity. With such a configuration, it is possible to achieve a state in which there is a greater difference in hydrophobicity (hydrophilicity) with respect to the hydrophobic portion 21, which has hydrophobicity, and it is possible to reliably move ions generated in the hydrophobic portion 21 to the hydrophilic portion 22.

[0048] It should be noted that the present invention is not limited to the configurations of the above-described embodiments, and many other embodiments can be obtained.

[0049] <Second embodiment> FIG. 5 is a perspective view of the carbon dioxide collector 100 according to the second embodiment of the present invention, and FIG. 6 is a vertical cross-sectional view of the carbon dioxide collector 100 according to the second embodiment of the present invention. For example, the carbon dioxide collector may be a rectangular plate-shaped carbon dioxide collector 100 as shown in FIG. 5. In the case of such a shape, the hydrophilic portion 122 arranged or formed in a thick rectangular shape is sandwiched between two hydrophobic portions 121 arranged or formed in a similarly thick rectangular shape to form the absorbing portion 102, and the filter portion 103 formed in two rectangular plate shapes is sandwiched between the absorbing portion 102. In this embodiment, a film-shaped absorber filter 131 is formed on the surface of the filter portion 103 facing the hydrophobic portion 121, and the absorber filter 131 is attached to and held by the holder 132. The hydrophilic portion 122, the hydrophobic portion 121, the absorber filter 131, and the holder 132 arranged in layers are fixed at their respective peripheral ends by the fixing portion 104 of the frame so that the opposing surfaces are in close contact with each other.

[0050] The rectangular plate-shaped carbon dioxide collector 100 of the second embodiment can be hung from a window frame or inside a car, realizing installation in a smaller space. In other words, the carbon dioxide collector 100 can be more suitably used in an ordinary home or the like.

[0051] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. Also, all modifications within the scope and meaning equivalent to the claims are included. [Industrial Applicability]

[0052] The carbon dioxide collector of the present invention can be used in the industry of manufacturing and selling devices for capturing carbon dioxide for use in ordinary households and the like. [Explanation of symbols]

[0053] 1...Carbon dioxide collector 2...Absorption section 21...Hydrophobic section 22…Hydrophilic part 3. Filter section 31...Absorbent filter 32...Holding body 4…Fixed part

Claims

1. An absorption section that absorbs carbon dioxide, The absorbing portion is A hydrophobic portion exhibiting hydrophobicity and a hydrophilic portion exhibiting hydrophilicity more than the hydrophobic portion, the hydrophobic portion and the hydrophilic portion are formed of a porous body, the porous body forming the hydrophobic portion includes an absorbent that reacts with carbon dioxide and ionizes, The hydrophobic portion and the hydrophilic portion are either integrally formed or disposed in contact with each other. Carbon dioxide collector.

2. A filter section is provided between the absorption section and the air, The filter portion has a property of not allowing the absorber to pass to the outside, The filter section and the absorption section are The absorption section is disposed so as to come into contact with air only through the filter section. The carbon dioxide collector according to claim 1.

3. The filter portion is provided between the hydrophobic portion and the air. The carbon dioxide collector according to claim 2.

4. It has a cylindrical shape, The hydrophobic portion is disposed so as to cover the outer peripheral side surface of the hydrophilic portion. The carbon dioxide collector according to claim 1.

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