JP2023175968A - Carbon dioxide permeation agent, carbon dioxide permeation device, and carbon dioxide permeation method - Google Patents

Abstract

To provide a carbon dioxide permeation device including a novel carbon dioxide permeation agent.SOLUTION: The carbon dioxide permeation device according to the present invention, includes a carbon dioxide permeation agent, a carbon dioxide supply unit, and a carbon dioxide permeation unit, the carbon dioxide permeation agent including a thin film made from a polymer including at least one species selected from the group consisting of rubber, polyethylene, cellulose and polyurethane, the carbon dioxide supply unit supplying the carbon dioxide permeation unit with a substance containing carbon dioxide i.e., mixed gas including carbon dioxide, hydrogen and methane, the carbon dioxide permeation unit including two sections connected with each other via the thin film, in which one section is supplied with the substance including carbon dioxide from the carbon dioxide supply unit, the other section is filled with a liquid so as to be in contact with the thin film, the carbon dioxide permeation unit being capable of separating carbon dioxide from the supplied substance containing carbon dioxide by the thin film selectively permeating carbon dioxide.SELECTED DRAWING: Figure 1

Description

The present invention relates to a carbon dioxide permeation agent, a carbon dioxide permeation device, and a carbon dioxide permeation method.

In recent years, as a countermeasure to the problem of global warming, the development of technology for separating and recovering carbon dioxide has been progressing. As a carbon dioxide separation and recovery method, Patent Document 1 discloses a technique for obtaining carbon dioxide from oxygen and nitrogen by a membrane permeation method based on the principle of molecular sieves.

However, there is a need for new methods that can permeate and separate carbon dioxide.

JP2021-24776A

Therefore, an object of the present invention is to provide a new carbon dioxide permeation agent and a carbon dioxide permeation device containing the same.

In order to achieve the above object, the carbon dioxide permeation agent of the present invention includes a thin film made of a polymer,
The thin film selectively permeates carbon dioxide.

The carbon dioxide permeation device of the present invention includes a carbon dioxide supply section and a carbon dioxide permeation section,
The carbon dioxide supply unit supplies a carbon dioxide-containing substance to the carbon dioxide permeation unit,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
The carbon dioxide permeation unit selectively permeates carbon dioxide contained in the supplied carbon dioxide-containing substance,
The carbon dioxide permeation section includes the carbon dioxide permeation agent of the present invention.

The carbon dioxide permeation method of the present invention includes a carbon dioxide supply step and a carbon dioxide permeation step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide permeation step,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
In the carbon dioxide permeation step, carbon dioxide contained in the supplied carbon dioxide-containing substance is selectively permeated by the carbon dioxide permeation agent of the present invention.

The present invention can provide a new carbon dioxide permeation agent and carbon dioxide permeation device.

FIG. 1 is a schematic diagram showing an example of a carbon dioxide permeation device according to a second embodiment. FIG. 2 is a schematic diagram showing another example of the carbon dioxide permeation device of Embodiment 2. FIG. 3 is a flowchart showing an example of processing in the carbon dioxide permeation method of Embodiment 3. FIG. 4 is a schematic diagram showing an example of a carbon dioxide absorption device of Embodiment 5. FIG. 5 is a schematic diagram showing another example of the carbon dioxide absorption device of Embodiment 5. FIG. 6 is a flowchart illustrating an example of processing in the carbon dioxide absorption method of Embodiment 6. FIG. 7 is a graph showing the carbon dioxide concentration in Reference Example 3. FIG. 8 is a graph showing the carbon dioxide concentration in Reference Example 3. FIG. 9 is a graph showing the carbon dioxide concentration in Reference Example 4. FIG. 10 is a graph showing the amount of decrease in volume of the carbon dioxide absorbent in Reference Example 4. FIG. 11 is a graph showing the carbon dioxide concentration in Reference Example 5. FIG. 12 is a graph showing carbon dioxide concentration in Example 1. FIG. 13 is a graph showing carbon dioxide concentration in Example 1. FIG. 14 is a graph showing the volume of rubber gloves in Example 2. FIG. 15 is a graph showing the volume of the rubber balloon in Example 2. FIG. 16 is a graph showing the volume of the rubber balloon in Example 3. FIG. 17 is a graph showing carbon dioxide concentration in Example 4. FIG. 18 is a graph showing carbon dioxide concentration in Example 4. FIG. 19 is a graph showing the volume of the Visking tube in Example 5. FIG. 20 is a graph showing carbon dioxide concentration in Example 5. FIG. 21 is a graph showing the volume of the Visking tube in Example 5. FIG. 4 is a graph showing the carbon dioxide concentration in Reference Example 1. FIG. 23 is a graph showing carbon dioxide concentration in Example 5. FIG. 24 is a graph showing the volume of the Visking tube in Example 5. FIG. 25 is a graph showing the volume of the rubber balloon in Example 3. FIG. 26 is a graph showing the volume of the rubber balloon in Example 3. FIG. 27 is a graph showing the volume of the Visking tube in Example 5. FIG. 28 is a graph showing the volume of the rubber balloon in Example 3. FIG. 29 is a graph showing the volume of the polyethylene bag in Example 4. FIG. 30 is a graph showing the volume of the polyethylene bag in Example 4. FIG. 31 is a graph showing the volume of polyurethane bags in Example 6. FIG. 32 is a graph showing the volume of polyurethane bags in Example 6. FIG. 33 is a graph showing the volume of polyethylene bags in Example 6. FIG. 34 is a graph showing the volume of the polyethylene bag in Example 4. FIG. 35 is a graph showing carbon dioxide concentration in Reference Example 1. FIG. 36 is a graph showing carbon dioxide concentration in Reference Example 2.

In the carbon dioxide permeable agent of the present invention, for example, the polymer is selected from the group consisting of cellulose, polyethylene terephthalate, high density polyethylene, low density polyethylene, polypropylene, polytetrafluoroethylene, polycarbonate, rubber, polyurethane, and acrylic. The form may include at least one of the following.

The carbon dioxide permeable agent of the present invention may be in a form, for example, in which the thin film does not permeate oxygen and nitrogen.

The carbon dioxide permeation agent of the present invention may be in the form of, for example, the thin film permeating the carbon dioxide in a heated state.

The carbon dioxide permeation agent of the present invention is capable of separating carbon dioxide from a mixed gas containing carbon dioxide and at least one of hydrogen and methane, for example, by selectively permeating carbon dioxide through the thin film. It may be in the form of

In the carbon dioxide permeation device of the present invention, for example, the carbon dioxide permeation section may be configured to permeate the carbon dioxide in a heated state.

In the carbon dioxide permeation device of the present invention, for example, the carbon dioxide permeation section includes two compartments, the two compartments are connected via the thin film of the carbon dioxide permeation agent, and one of the compartments is connected through the thin film of the carbon dioxide permeation agent. The carbon dioxide-containing substance may be supplied from the carbon dioxide supply section, and the other compartment may be filled with a liquid so as to be in contact with the thin film. Further, the carbon dioxide-containing substance is a gas mixture containing carbon dioxide and at least one of hydrogen and methane, and the thin film selectively permeates carbon dioxide, thereby causing the carbon dioxide to be supplied to the one compartment. It may be possible to separate carbon dioxide from the mixed gas into the liquid filled in the other compartment.

In the carbon dioxide permeation method of the present invention, for example, in the carbon dioxide permeation step, the carbon dioxide may be permeated in a heated state.

In the carbon dioxide permeation method of the present invention, for example, in the carbon dioxide permeation step, the carbon dioxide is permeated through a carbon dioxide permeation section, and the carbon dioxide permeation section includes the carbon dioxide permeation agent and two compartments. , the two compartments are connected via the thin film of the carbon dioxide permeable agent, one of the compartments is supplied with the carbon dioxide-containing substance from the carbon dioxide supply unit, and the other compartment is supplied with the carbon dioxide-containing substance. may be filled with liquid so as to be in contact with the thin film. Further, the carbon dioxide-containing substance is a gas mixture containing carbon dioxide and at least one of hydrogen and methane, and in the carbon dioxide permeation step, the thin film selectively permeates carbon dioxide to The method may be such that carbon dioxide is separated from the mixed gas supplied to the second compartment into the liquid filling the other compartment.

Embodiments of the present invention will be described. Note that the present invention is not limited to the following embodiments. In addition, in each of the following figures, the same parts are given the same reference numerals. In addition, the descriptions of each embodiment can be used to refer to each other unless otherwise specified. Furthermore, the configurations of each embodiment can be combined unless otherwise specified. Unless otherwise specified, terms used herein can be used with the meanings commonly used in the art.

[Embodiment 1]
(carbon dioxide permeation agent)
The carbon dioxide permeation agent of this embodiment includes a polymer thin film, and the thin film selectively permeates carbon dioxide (CO ₂ ). Other than this point, there are no particular restrictions.

Examples of the polymer include cellulose, polyethylene terephthalate, high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), polytetrafluoroethylene (PTFE), polycarbonate, rubber, polyurethane, and acrylic. It will be done. Examples of the rubber include latex. In addition, in this specification, when it describes simply as polyethylene hereafter, it refers to low density polyethylene. The carbon dioxide permeation agent may contain one type of the polymer, or may contain multiple types of the polymer.

In the carbon dioxide permeation agent of this embodiment, the content of the polymer is not particularly limited and can be set as appropriate.

The carbon dioxide permeable agent may contain components other than the polymer, for example. Components other than the polymer are not particularly limited.

The thickness of the thin film is not particularly limited as long as it can selectively permeate carbon dioxide, and is, for example, 0.005 to 0.1 mm, specifically, 0.005 mm, 0.03 mm, 0.04 mm, or 0.08 mm. can give. Note that, for example, rubber balloons and gloves have a thickness in the range of 0.005 to 0.1 mm when inflated.

The carbon dioxide permeable agent, for example, permeates carbon dioxide contained in a carbon dioxide-containing substance. The carbon dioxide-containing substance may be a gas, that is, a carbon dioxide-containing gas, or a liquid, that is, a carbon dioxide-containing solution. The carbon dioxide-containing gas is not particularly limited, and examples include combustion exhaust gas, indoor air, and the atmosphere. The concentration of carbon dioxide in the carbon dioxide-containing gas is not particularly limited, and is greater than 0 and 100% or less. The carbon dioxide-containing solution is not particularly limited, and examples thereof include carbonated water, carbon dioxide water, and the like. In the carbonated water, carbon dioxide mainly exists as carbonate ions or bicarbonate ions. On the other hand, in the carbon dioxide water, carbon dioxide exists in a non-ionized state. Alternatively, the carbon dioxide-containing gas may be passed through a liquid such as water. The concentration of carbon dioxide in the carbon dioxide-containing solution is not particularly limited, and is greater than 0 and 0.14 g/dl or less.

The thin film selectively permeates carbon dioxide. Specifically, "permeate carbon dioxide selectively" means, for example, to permeate carbon dioxide but not to permeate substances other than carbon dioxide. The above-mentioned "not transmitting" includes, for example, "almost not transmitting". Examples of substances that the thin film does not permeate include oxygen and nitrogen. Furthermore, "selectively permeating carbon dioxide" means, for example, that the permeation rate of substances other than carbon dioxide is slower than the permeation rate of carbon dioxide. Examples of substances whose permeation rate is slower than that of carbon dioxide include hydrogen and methane. As will be described later, hydrogen and methane do not permeate from the gas phase to the liquid phase, for example, when one surface of the thin film is in contact with the gas phase and the other surface is in contact with the liquid phase. do not. Further, for example, when both surfaces of the thin film are in contact with a liquid phase, the liquid does not permeate from one of the liquid phases to the other liquid phase. In this case, for example, each of the liquid phases may contain liquids in which the solubility of substances other than carbon dioxide (substances to be separated; oxygen, nitrogen, hydrogen, methane, etc.) contained in the carbon dioxide-containing substance is different. Can be used.

The carbon dioxide permeation agent is capable of separating carbon dioxide from a mixed gas containing carbon dioxide and at least one of hydrogen and methane, for example, by selectively permeating carbon dioxide through the thin film. In this case, for example, as described below, the thin film can separate carbon dioxide from the gas mixture supplied to one compartment into a liquid (e.g., water, aqueous solution, etc.) filled in the other compartment. be. Also, for example, the thin membrane can separate carbon dioxide from the liquid supplied to one compartment to the liquid filled in the other compartment.

In this embodiment, "permeates carbon dioxide", "does not permeate carbon dioxide", and "almost does not permeate carbon dioxide" can be determined by known methods, such as JIS K7126-1 (2006 Carbon dioxide permeability, etc. measured in accordance with For example, as shown in the examples described later, the thin film is formed into a bag, carbon dioxide is poured into the bag, and the presence or absence and speed of permeation of carbon dioxide are determined based on changes in the volume of the bag over time. You can check it out. Note that, for example, the permeation of substances other than carbon dioxide can be similarly determined.

The contact conditions between the carbon dioxide permeable agent and the carbon dioxide-containing substance are not particularly limited, and for example, the carbon dioxide-containing substance is placed in a container containing the carbon dioxide permeable agent, and the carbon dioxide-containing substance is placed at room temperature (e.g., 24° C.); Contact can be made by leaving it for 30 minutes, 1 hour, 1.5 hours, 2 hours, 5 hours, and 6 hours.

The carbon dioxide permeation agent may allow the thin film to permeate the carbon dioxide in a heated state. The heating conditions are not particularly limited, and may be, for example, 5 to 80°C, specifically, for example, 50°C. In this case, the carbon dioxide permeable agent may be heated, or the carbon dioxide may be heated. The heating can, for example, increase the amount of carbon dioxide that permeates.

According to the carbon dioxide permeation agent of the present embodiment, the thin film selectively permeates carbon dioxide, thereby making it possible to separate carbon dioxide from the carbon dioxide-containing substance, for example. Further, for example, by using the thin film of the carbon dioxide permeation agent in a state where one surface is in contact with the gas phase and the other surface is in contact with the liquid phase, a mixed gas containing carbon dioxide can be used to remove the carbon dioxide from the liquid phase. , carbon dioxide can be separated more suitably.

(carbon dioxide absorbent)
The carbon dioxide absorbent (first carbon dioxide absorbent) of the present embodiment includes a carbon dioxide absorption section, the carbon dioxide absorption section includes the carbon dioxide permeation agent of the present invention, and the carbon dioxide absorption section includes a carbon dioxide absorption section. The inside is sealed, and the thin film of the carbon dioxide permeable agent selectively permeates carbon dioxide, so that carbon dioxide is absorbed from the outside of the carbon dioxide absorption section into the inside.

The sealed interior of the carbon dioxide absorption section is filled with, for example, a gas or liquid having a lower carbon dioxide concentration than the outside. Due to these, carbon dioxide permeates from the outside to the inside of the carbon dioxide absorption section through the thin film, and is absorbed into the inside of the carbon dioxide absorption section.

The shape of the carbon dioxide absorbent of this embodiment is not particularly limited, and examples include bubble wrap, bag, and tube shapes.

The volume of the carbon dioxide absorption section increases and decreases due to, for example, absorption and release of the carbon dioxide. In the carbon dioxide absorption section, the thin film is formed of a stretchable material, for example. As a result, the thin film expands and contracts due to absorption and release of the carbon dioxide, and the volume of the carbon dioxide absorption section changes.

[Embodiment 2]
(Carbon dioxide permeation device)
FIG. 1 is a schematic diagram showing an example of a carbon dioxide permeation device 1 of this embodiment. As shown in FIG. 1, the carbon dioxide permeation device 1 includes a carbon dioxide supply section 11 and a carbon dioxide permeation section 12. The size, forming material, etc. of each component included in the carbon dioxide permeation device 1 are not particularly limited, and can be set as appropriate. The carbon dioxide permeation device of this embodiment can also be called, for example, a carbon dioxide separation device.

The carbon dioxide supply section 11 supplies a carbon dioxide-containing substance to the carbon dioxide permeation section 12 . The carbon dioxide-containing substance is the same as the carbon dioxide-containing substance in Embodiment 1.

The carbon dioxide supply section 11 is not particularly limited as long as it can supply the carbon dioxide-containing substance to the carbon dioxide permeation section 12. For example, the carbon dioxide supply unit 11 may supply the carbon dioxide-containing gas or the carbon dioxide-containing solution into the carbon dioxide permeation unit 12, or may supply the carbon dioxide-containing solution into the carbon dioxide permeation unit 12. The carbon dioxide-containing gas may be supplied into the liquid. Specifically, the carbon dioxide supply section 11 may be, for example, a pipe, a hose, etc., a vent, or a bubble-shaped gas supply device such as a bubble former.

The carbon dioxide permeation unit 12 selectively permeates carbon dioxide contained in the supplied carbon dioxide-containing substance. The carbon dioxide permeation section 12 includes a carbon dioxide permeation agent 121 . The carbon dioxide permeable agent 121 is the carbon dioxide permeable agent of the first embodiment.

As shown in FIG. 1, the carbon dioxide permeation section 12 includes a first chamber 12A and a second chamber 12B, and the first chamber 12A and the second chamber 12B are connected via a carbon dioxide permeation agent 121. You can. Then, the carbon dioxide supply unit 11 supplies carbon dioxide to the first chamber 12A, and the carbon dioxide permeation agent 121 selectively permeates the carbon dioxide contained in the supplied carbon dioxide-containing substance. Carbon dioxide is sent from the first chamber 12A to the second chamber 12B.

In the carbon dioxide permeation device 1 of this embodiment, the second chamber 12B may contain gas (for example, air, etc.), may contain a liquid phase or a liquid layer, or may contain both. You may be The liquid layer is, for example, a structure that covers the surface of a thin film, and specifically, for example, the liquid may be caused to flow on the surface of the film, or it may be a thin structure that is left still and covers the surface. The liquid phase has, for example, a thicker structure than the liquid layer, and specifically, for example, the partition (second chamber 12B) may be filled with the liquid. The liquid is not particularly limited, and includes, for example, water, an aqueous solution, and the like. In the liquid, for example, the solubility of substances other than carbon dioxide (substances to be separated; oxygen, nitrogen, hydrogen, methane, etc.) contained in the carbon dioxide-containing substance is lower than the solubility of carbon dioxide. It can be a liquid. Even when the second chamber 12B contains liquid, for example, the carbon dioxide can be sufficiently permeated therethrough without hindering its permeation.

In this way, the carbon dioxide permeation device 1 of the present embodiment includes two compartments (first chamber 12A and second chamber 12B), and the two compartments include the carbon dioxide permeation agent (carbon dioxide permeation agent 121). are connected through the thin film, one of the compartments (first chamber 12A) is supplied with the carbon dioxide-containing substance from the carbon dioxide supply unit (carbon dioxide supply unit 11), and the other compartment is supplied with the carbon dioxide-containing substance from the carbon dioxide supply unit (carbon dioxide supply unit 11). (Second chamber 12B) is filled with the liquid so as to be in contact with the thin film (forming the liquid phase), or the liquid is layered (forming the liquid layer). ).

By containing the liquid in the second chamber 12B, for example, when the carbon dioxide-containing substance contains carbon dioxide and hydrogen, carbon dioxide can be easily separated. Specifically, for example, when the carbon dioxide supply unit 11 supplies the carbon dioxide-containing substance containing carbon dioxide and at least one of hydrogen and methane to the first chamber 12A, the carbon dioxide permeation agent 121 supplies the carbon dioxide containing substance to the first chamber 12A. While the carbon dioxide contained in the carbon-containing material passes through, the presence of the liquid inhibits the permeation of hydrogen and methane gas. Thereby, carbon dioxide from which hydrogen and methane gas have been separated and removed can be sent from the first chamber 12A to the second chamber 12B. Note that, as shown in Example 5, which will be described later, by using a cellulose membrane and water, it is possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane gas.

As described above, in the carbon dioxide permeation device 1 of the present embodiment, when the carbon dioxide-containing substance is a mixed gas containing carbon dioxide and at least one of hydrogen and methane, the thin film selectively removes carbon dioxide. Carbon dioxide can be separated from the mixed gas supplied to the one compartment into the liquid filling the other compartment.

The carbon dioxide permeation device 1 of this embodiment may further include, for example, a carbon dioxide release part, and the carbon dioxide permeated by the carbon dioxide permeation part 12 may be released by the carbon dioxide release part. The carbon dioxide releasing section may be, for example, a pipe, a hose, etc., or may be a vent. The carbon dioxide release section is provided, for example, in the second chamber 12B.

The carbon dioxide permeation section 12 may, for example, permeate the carbon dioxide in a heated state. In this case, as shown in FIG. 2, the carbon dioxide permeation section 12 may be heated by the heating section 2. The heating unit 2 may or may not be included in the carbon dioxide permeation device 1. The heating section 2 is not particularly limited as long as it can heat the carbon dioxide permeation section 12, and a general heating device can be used. The heating unit 2 may be, for example, a heating device using reflux of hot water. Note that the present invention is not limited to this, and for example, the carbon dioxide-containing substance supplied from the carbon dioxide supply unit 11 may be in a heated state. The description of Embodiment 1 can be referred to for the conditions of the heating and the release of carbon dioxide.

[Embodiment 3]
(Carbon dioxide permeation method)
The carbon dioxide permeation method of this embodiment includes a carbon dioxide supply step and a carbon dioxide permeation step. The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide permeation step. In the carbon dioxide permeation step, carbon dioxide contained in the supplied carbon dioxide-containing substance is selectively permeated by the carbon dioxide permeation agent. In the carbon dioxide permeation method of this embodiment, other configurations and conditions are not particularly limited. The carbon dioxide permeation method of this embodiment can also be called, for example, a carbon dioxide separation method.

The carbon dioxide permeation method of this embodiment will be explained using FIG. 3. FIG. 3 is a flowchart showing an example of the carbon dioxide permeation method. The carbon dioxide permeation method of this embodiment can be carried out as follows using, for example, the carbon dioxide permeation device 1 shown in FIG. Note that the carbon dioxide permeation method of this embodiment is not limited to the use of the carbon dioxide permeation device 1 shown in FIG. The flowchart in FIG. 3 is an example of the processing order of each step, and the present invention is not limited to this order, and each step may be performed simultaneously as long as the carbon dioxide permeation reaction can be performed. , may be moved back or forth.

In the carbon dioxide supply step (S101), the carbon dioxide supply unit 11 supplies a carbon dioxide-containing substance to the carbon dioxide permeation step (S102). The carbon dioxide-containing substance is the same as the carbon dioxide-containing substance in Embodiment 1.

Next, the carbon dioxide permeation step (S102) selectively permeates carbon dioxide contained in the supplied carbon dioxide-containing substance by the carbon dioxide permeation agent 121 of the carbon dioxide permeation section 12, and ends (END ). In the carbon dioxide permeation step (S102), for example, the carbon dioxide may be permeated in a heated state.

(Carbon dioxide absorption method)
The carbon dioxide absorption method (first carbon dioxide absorption method) of this embodiment includes a carbon dioxide supply step and a carbon dioxide absorption step. The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide absorption step. In the carbon dioxide absorption step, carbon dioxide contained in the supplied carbon dioxide-containing substance is selectively permeated by the carbon dioxide absorbent (first carbon dioxide absorbent), thereby absorbing carbon dioxide. absorbs carbon dioxide. In the carbon dioxide absorption method of this embodiment, other configurations and conditions are not particularly limited.

[Embodiment 4]
(carbon dioxide absorbent)
In recent years, as a countermeasure to the problem of global warming, the development of technology for separating and recovering carbon dioxide has been progressing. As a carbon dioxide separation and recovery method, Patent Document 2 discloses a technique in which carbon dioxide is absorbed into an amine solution containing an amine.
Patent Document 2: Japanese Patent Application Publication No. 2021-095357

However, there is a need for new methods that can separate and recover carbon dioxide.

In order to achieve the above object, the carbon dioxide absorbent of the present invention (second carbon dioxide absorbent) contains a polymer,
The polymer absorbs carbon dioxide.

The present invention can provide a new carbon dioxide absorbent.

In the carbon dioxide absorbent of the present invention, for example, the polymer is selected from the group consisting of cellulose, polyethylene terephthalate, high density polyethylene, low density polyethylene, polypropylene, polytetrafluoroethylene, polycarbonate, rubber, polyurethane, and acrylic. The form may include at least one of the following.

The carbon dioxide absorbent of the present invention may be, for example, in a form in which the polymer releases the absorbed carbon dioxide in a heated state. The carbon dioxide absorbent of the present invention may be in a form in which, for example, the heated state is a state heated to 50° C. or higher.

The carbon dioxide absorbent of this embodiment includes a polymer, and the polymer absorbs carbon dioxide (CO ₂ ). Other than this point, there are no particular restrictions.

Examples of the polymer include cellulose, polyethylene terephthalate, high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), polytetrafluoroethylene (PTFE), polycarbonate, rubber, polyurethane, and acrylic. It will be done. Examples of the rubber include latex. The carbon dioxide absorbent may contain one type of the polymer, or may contain multiple types of the polymer.

In the carbon dioxide absorbent of this embodiment, the content of the polymer is not particularly limited and can be set as appropriate.

The carbon dioxide absorbent may contain components other than the polymer, for example. Components other than the polymer are not particularly limited.

The shape of the carbon dioxide absorbent is not particularly limited, and may be, for example, a container shape, a sheet shape, a mesh shape, a bubble wrap shape, a bead shape, or the like. The size of the carbon dioxide absorbent is not particularly limited as long as it can absorb carbon dioxide.

The carbon dioxide absorbent absorbs, for example, carbon dioxide contained in a carbon dioxide-containing substance. The carbon dioxide-containing substance may be a gas, that is, a carbon dioxide-containing gas, or a liquid, that is, a carbon dioxide-containing solution. The carbon dioxide-containing gas is not particularly limited, and examples include combustion exhaust gas, indoor air, and the atmosphere. The concentration of carbon dioxide in the carbon dioxide-containing gas is not particularly limited, and is greater than 0 and 100% or less. The carbon dioxide-containing solution is not particularly limited, and examples thereof include carbonated water, carbon dioxide water, and the like. In the carbonated water, carbon dioxide mainly exists as carbonate ions or bicarbonate ions. On the other hand, in the carbon dioxide water, carbon dioxide exists in a non-ionized state. Alternatively, the carbon dioxide-containing gas may be passed through a liquid such as water. The concentration of carbon dioxide in the carbon dioxide-containing solution is not particularly limited, and is greater than 0 and 0.14 g/dl% or less.

The contact conditions between the carbon dioxide absorbent and the carbon dioxide-containing substance are not particularly limited, and for example, the carbon dioxide-containing substance is placed in a container containing the carbon dioxide absorbent, and the carbon dioxide-containing substance is placed in a container containing the carbon dioxide absorbent, and the carbon dioxide-containing substance is placed in a container containing the carbon dioxide absorbent, and They can be brought into contact by standing still for a period of time.

The temperature at which the carbon dioxide absorbent and the carbon dioxide-containing substance are brought into contact may be, for example, room temperature, or the carbon dioxide absorbent may be cooled.

For example, the volume of the carbon dioxide absorbent increases due to absorption of the carbon dioxide.

Moreover, the carbon dioxide absorbent of this embodiment may release the absorbed carbon dioxide.

Specifically, for example, by bringing the carbon dioxide absorbent that has absorbed the carbon dioxide into contact with a gas or liquid containing a lower concentration of carbon dioxide, the absorbed carbon dioxide can be released.

The release can be performed, for example, while the polymer is heated. The temperature in the heated state is, for example, 5 to 80°C, and specifically, for example, 20°C or higher and 50°C or higher. The temperature in the heated state may be higher than, for example, the temperature when absorbing the carbon dioxide.

For example, by leaving a container containing the carbon dioxide absorbent that has absorbed the carbon dioxide at 50° C. for 5 hours, the absorbed carbon dioxide can be released.

[Embodiment 5]
(carbon dioxide absorption device)
The carbon dioxide absorption device of the present invention includes a carbon dioxide supply section and a carbon dioxide absorption section,
The carbon dioxide supply unit supplies a carbon dioxide-containing substance to the carbon dioxide absorption unit,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
The carbon dioxide absorption unit absorbs carbon dioxide contained in the supplied carbon dioxide-containing substance,
The carbon dioxide absorbing section includes the carbon dioxide absorbent of the present invention.

In the carbon dioxide absorption device of the present invention, for example, the carbon dioxide absorption section is heatable, and the carbon dioxide absorption section further releases the absorbed carbon dioxide in a heated state. It may be.

FIG. 4 is a schematic diagram showing an example of the carbon dioxide absorption device 3 of this embodiment. As shown in FIGS. 4A and 4B, the carbon dioxide absorption device 3 includes a carbon dioxide supply section 31 and a carbon dioxide absorption section 32. The size, forming material, etc. of each component included in the carbon dioxide absorption device 3 are not particularly limited, and can be set as appropriate.

The carbon dioxide supply section 31 supplies a carbon dioxide-containing substance to the carbon dioxide absorption section 32 . The carbon dioxide-containing substance is the same as the carbon dioxide-containing substance in Embodiment 4.

The carbon dioxide supply section 31 is not particularly limited as long as it can supply the carbon dioxide-containing substance to the carbon dioxide absorption section 32. For example, the carbon dioxide supply unit 31 may supply the carbon dioxide-containing gas or the carbon dioxide-containing solution into the carbon dioxide absorption unit 32, or may supply the carbon dioxide-containing solution into the carbon dioxide absorption unit 32. The carbon dioxide-containing gas may be supplied into the liquid. Specifically, the carbon dioxide supply section 31 may be, for example, a pipe, a hose, etc., a vent, or a bubble gas supply device such as a bubble former.

The carbon dioxide absorption unit 32 absorbs carbon dioxide contained in the supplied carbon dioxide-containing substance. The carbon dioxide absorption section 32 includes a carbon dioxide absorbent 321. The carbon dioxide absorbent 321 is the carbon dioxide absorbent of the fourth embodiment.

For example, as shown in FIG. 4(A), the carbon dioxide absorbing portion 32 may be a container-shaped carbon dioxide absorbent 321 itself, or as shown in FIG. A container containing carbon absorbent 321 may also be used.

The carbon dioxide absorption device 3 of this embodiment further includes a carbon dioxide release section 33, as shown in FIGS. 4(A) and 4(B). The carbon dioxide release unit 33 can release, for example, carbon dioxide absorbed by the carbon dioxide absorption unit 32 . Specifically, the carbon dioxide release section 33 may be, for example, a pipe, a hose, or the like, or may be a vent. The carbon dioxide release section 33 may have a common structure with the carbon dioxide supply section 31, for example.

For example, the carbon dioxide absorption section 32 may be heatable. In this case, as shown in FIGS. 5A and 5B, the carbon dioxide absorption section 32 is heated by the heating section 4. The heating unit 4 may or may not be included in the carbon dioxide absorption device 3. The heating unit 4 is not particularly limited as long as it can heat the carbon dioxide absorption unit 32, and a general heating device can be used. The heating unit 4 may be, for example, a heating device using reflux of hot water. The description of Embodiment 4 can be referred to for the conditions of the heating and the release of carbon dioxide. The carbon dioxide absorption unit 32 can release the absorbed carbon dioxide in a heated state.

[Embodiment 6]
(Carbon dioxide absorption method)
The carbon dioxide absorption method (second carbon dioxide absorption method) of the present invention includes a carbon dioxide supply step and a carbon dioxide absorption step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide absorption step,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
In the carbon dioxide absorption step, carbon dioxide contained in the supplied carbon dioxide-containing substance is absorbed by the carbon dioxide absorbent of the present invention.

The carbon dioxide absorption method of the present invention further includes, for example, a carbon dioxide release step, in which the carbon dioxide absorbent is heated and the absorbed carbon dioxide is released. It may be a form.

The carbon dioxide absorption method of this embodiment includes a carbon dioxide supply step and a carbon dioxide absorption step. The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide absorption step. In the carbon dioxide absorption step, carbon dioxide contained in the supplied carbon dioxide-containing substance is absorbed by the carbon dioxide absorbent. In the carbon dioxide absorption method of this embodiment, other configurations and conditions are not particularly limited.

The carbon dioxide absorption method of this embodiment will be explained using FIG. 6(A). FIG. 6(A) is a flowchart showing an example of the carbon dioxide absorption method. The carbon dioxide absorption method of this embodiment can be implemented as follows using, for example, the carbon dioxide absorption device 3 shown in FIG. Note that the carbon dioxide absorption method of this embodiment is not limited to the use of the carbon dioxide absorption device 3 shown in FIG. The flowchart in FIG. 6(A) is an example of the processing order of each step, and the present invention is not limited to this order, and each step may be performed simultaneously to the extent that the carbon dioxide absorption reaction can be performed. You can also move it back and forth.

In the carbon dioxide supply step (S201), the carbon dioxide supply unit 31 supplies a carbon dioxide-containing substance to the carbon dioxide absorption step (S202). The carbon dioxide-containing substance is the same as the carbon dioxide-containing substance in Embodiment 4.

Next, the carbon dioxide absorption step (S202) absorbs carbon dioxide contained in the supplied carbon dioxide-containing substance by the carbon dioxide absorbent 321 of the carbon dioxide absorption unit 32, and ends (END).

The carbon dioxide absorption method of this embodiment may further include a carbon dioxide release step (S203), as shown in FIG. 6(B).

The carbon dioxide releasing step (S203) releases the absorbed carbon dioxide while the carbon dioxide absorbent 321 is heated by the carbon dioxide releasing unit 33, and ends (END). In the carbon dioxide release step (S203), the carbon dioxide absorption unit 12 may be heated by the heating unit 2, for example.

Next, examples of the present invention will be described. However, the present invention is not limited to the following examples. Commercially available reagents were used according to their protocols unless otherwise indicated.

[Example 1]
It was confirmed that the polymer allows carbon dioxide to pass through.

Approximately 150 ml of 100% carbon dioxide was placed in polyethylene (low density polyethylene) bags (0.03 mm and 0.08 mm thick, commercially available). The bag was inserted into a 450 ml wide-mouthed glass bottle and sealed with a lid. This was left standing at room temperature (24°C) for 30 minutes, 1 hour, 1.5 hours, 2 hours, and 5 hours. After the above-mentioned standing, the gas in the area between the wall of the glass bottle and the bag was detected using a carbon dioxide detector (XP-3140, manufactured by COSMO) (for low concentration) and (CX-6000, manufactured by RIKEN KEIKI). ) (for high concentration) to measure carbon dioxide concentration.

The results are shown in FIG. 12. FIG. 12 is a graph showing the carbon dioxide concentration. In FIG. 12, the vertical axis shows carbon dioxide concentration (%), and the horizontal axis shows 30 minutes, 1 hour, 1.5 hours, 2 hours, and 5 hours from the left. The white graph shows the results when the bag thickness is 0.08 mm, and the black graph shows the results when the bag thickness is 0.03 mm. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 12, when the bag thickness was 0.03 mm, the carbon dioxide concentration reached 6.8% after 30 minutes and reached 11.3% after 5 hours. In addition, when the bag thickness was thicker, 0.08 mm, the carbon dioxide concentration was low at 0.75% after 30 minutes, but increased as the standing time increased, and it was 11.3% after 5 hours. .

The results showed that carbon dioxide permeates through the polyethylene bag and that the passage is related to the thickness of the polyethylene bag.

Next, an experiment was conducted in the same manner except that the experimental conditions were 50° C., with a standing time of 30 minutes and a thickness of the polyethylene bag of 0.08 mm.

The results are shown in FIG. 13. FIG. 13 is a graph showing the carbon dioxide concentration. In FIG. 13, the vertical axis shows carbon dioxide concentration (%), and the horizontal axis shows 24°C and 50°C from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of 5 samples.

As shown in FIG. 13, when the temperature was 50°C, the carbon dioxide concentration reached 6.5% after 30 minutes, which was a large increase compared to the result when the temperature was 24°C. Note that the above results when the temperature was 50°C were comparable to the results when the 0.03 mm polyethylene bag was used at 24°C.

From this result, it was found that the permeation of carbon dioxide through the polyethylene bag was temperature dependent.

As described above, it was confirmed that the polymer allows carbon dioxide to permeate.

[Example 2]
It was confirmed that rubber permeates carbon dioxide.

150 ml of 100% carbon dioxide was injected under pressure into a latex glove (commercially available). The gloves were sealed and left at room temperature for 2 and 6 hours. Immediately after the sealing and after the glove was left standing, the volume of the glove was measured. The volume was measured by filling a container with water, submerging the glove in the water, measuring the amount of water removed, and determining the volume of the glove. Then, assuming the volume immediately after the sealing as 1, the volume ratio of the glove after being left still was calculated as a relative value.

The results are shown in FIG. FIG. 14 is a graph showing the volume of the glove. In FIG. 14, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates, from the left, immediately after the sealing, 2 hours, and 6 hours later. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 14, the volume of the glove inflated with carbon dioxide decreased over time. The volume of the glove immediately after the sealing was 600 to 700 ml. The results showed that carbon dioxide permeated through the rubber (latex) glove over time.

Next, an experiment was conducted in the same manner except that a rubber balloon (commercially available) was used.

The results are shown in FIG. 15. FIG. 15 is a graph showing the volume of the balloon. In FIG. 15, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates, from the left, immediately after the sealing, 1 hour, 2 hours, and 5 hours later. Note that the volume value was the average value of the measured values of three samples in total.

As shown in FIG. 15, the volume of the balloon inflated with carbon dioxide decreased over time. The results showed that carbon dioxide permeated through the rubber balloon over time.

As described above, it was confirmed that rubber permeates carbon dioxide.

[Example 3]
It was confirmed that rubber selectively permeates carbon dioxide. Furthermore, it was confirmed that by using a rubber membrane and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.

A rubber balloon (commercially available) was inflated to a moderate level by human exhalation. The balloon was sealed and placed in a 4 liter glass bottle filled with 80% carbon dioxide, and allowed to stand for 5 hours. Thereafter, the balloon was taken out of the glass bottle and left indoors for 4 hours. The volume of the balloon was calculated in the same manner as in Example 2 immediately after the expansion, after being left still under carbon dioxide, and after being left still in the room.

The results are shown in FIG. 16. FIG. 16 is a graph showing the volume of the balloon. In FIG. 16, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates, from the left, immediately after the expansion, after standing under carbon dioxide, and after standing in the room. Note that the volume value was the average value of the measured values of a total of 5 samples.

As shown in FIG. 16, by leaving the balloon that had been inflated to a moderate level under the carbon dioxide at a high concentration, the balloon expanded to about 1.8 times its volume after being left for 5 hours. Became. Thereafter, after being allowed to stand still in the room for 4 hours, the volume of the balloon decreased to approximately the same level as the volume immediately after inflation. In addition, even if the balloon was left in the room after being left still in the room, no further reduction in volume occurred. This result showed that the rubber balloon selectively allows carbon dioxide to pass through, but does not allow substances other than carbon dioxide (eg, oxygen and nitrogen) to pass through.

Next, the permeation of carbon dioxide into the liquid was confirmed using the rubber balloon.

200-450 ml of 100% carbon dioxide were injected into a rubber balloon as in Example 2. The balloon was placed in a wide-mouthed glass bottle with a volume of 450 ml, and then water was filled to the full capacity between the wall of the glass bottle and the balloon, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 4 hours, 8 hours, and 21 hours. Immediately after the sealing and after the standing, the volume of the balloon was calculated in the same manner as in Example 2.

The results are shown in FIG. 25. FIG. 25 is a graph showing the volume of the balloon. In FIG. 25, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates 4 hours, 8 hours, and 21 hours from the left. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 25, 60% of carbon dioxide was released after 4 hours of standing, and 75% of carbon dioxide was released after 8 hours. After 21 hours, the carbon dioxide in the balloon was almost completely released. In this way, it was possible to confirm the permeation of carbon dioxide into the liquid using the rubber balloon.

Next, using the rubber balloon, it was confirmed that hydrogen permeates through the balloon and that the hydrogen permeation rate is slower than the carbon dioxide permeation rate.

100% hydrogen was similarly injected into a rubber balloon. The balloon was sealed and left at room temperature for 5 and 10 hours. The volume of the balloon was measured immediately after the sealing and after the balloon was left standing.

The results are shown in FIG. 26. FIG. 26 is a graph showing the volume of the balloon. In FIG. 26, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours and 10 hours from the left. Note that the volume value indicates a measured value of one sample.

As shown in FIG. 26, after standing still for 5 hours, the volume of the balloon significantly decreased compared to immediately after sealing, and the relative value of the volume was 0.71. Moreover, after standing still for 10 hours, it further decreased, and the relative value of the volume was 0.44. From this, it was found that the rubber balloon permeates hydrogen. Note that, as described above, when carbon dioxide was used, the relative value of the volume was 0.42 after standing for 4 hours. From this, it was found that the permeation rate of carbon dioxide was faster than the permeation rate of hydrogen. From the above, it was shown that carbon dioxide can selectively permeate the balloon.

Next, using the rubber balloon, it was confirmed that the balloon permeates methane and that the permeation rate of methane is slower than the permeation rate of carbon dioxide.

100% methane (manufactured by AsOne) was similarly injected into a rubber balloon. The balloons were sealed and left at room temperature for 5, 10, and 15 hours. The volume of the balloon was measured immediately after the sealing and after the balloon was left standing.

The results are shown in FIG. FIG. 28 is a graph showing the volume of the balloon. In FIG. 28, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours, 10 hours, and 15 hours from the left. Note that the volume value was the average value of the measured values of a total of four samples.

As a result, after standing for 5 hours, the volume of the balloon was slightly reduced compared to immediately after sealing, and the relative value of the volume was 0.91. Moreover, after standing still for 10 hours, it further decreased slightly, and the relative value of the volume was 0.79. Moreover, after standing still for 15 hours, it further decreased slightly, and the relative value of the volume was 0.66. From this, it was found that the rubber balloon permeates methane. Note that, as described above, when carbon dioxide was used, the relative value of the volume was 0.42 after standing for 4 hours. From this, it was found that the permeation rate of carbon dioxide was faster than that of methane. From the above, it was shown that carbon dioxide can selectively permeate the balloon.

Next, using the rubber balloon, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase.

100% hydrogen was similarly injected into a rubber balloon. The balloon was placed in a wide-mouthed glass bottle with a volume of 450 ml, and then water was filled to the full capacity between the wall of the glass bottle and the balloon, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the standing, the volume of the balloon was calculated in the same manner.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase in the rubber balloon.

Next, using the rubber balloon, it was confirmed that methane did not permeate from the gas phase to the liquid phase.

100% methane (manufactured by AsOne) was similarly injected into a rubber balloon. The balloon was placed in a wide-mouthed glass bottle with a volume of 450 ml, and then water was filled to the full capacity between the wall of the glass bottle and the balloon, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the standing, the volume of the balloon was calculated in the same manner.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that methane did not permeate from the gas phase to the liquid phase in the rubber balloon.

As described above, it was confirmed that rubber selectively permeates carbon dioxide. Furthermore, it was confirmed that by using a rubber membrane and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.

[Example 4]
It was confirmed that polyethylene permeates carbon dioxide in liquid. Furthermore, it was confirmed that by using a polyethylene membrane and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.

First, it was confirmed that carbon dioxide permeated through the polyethylene bag by measuring the volume of the polyethylene bag.

A polyethylene bag (0.04 mm thick, commercially available) was moderately inflated with human exhalation. The bag was sealed, placed in a 4 liter glass bottle filled with 80% carbon dioxide, and left to stand for 5 hours. Thereafter, the bag was taken out of the glass bottle and left indoors for 4 and 9 hours. The volume of the bag was calculated in the same manner as in Example 2 immediately after the expansion, after being left still under carbon dioxide, and after being left still in the room.

The results are shown in FIG. 34. FIG. 34 is a graph showing the volume of the bag. In FIG. 34, the vertical axis shows the relative value of the volume, and the horizontal axis shows, from the left, immediately after the expansion, after standing under carbon dioxide, 4 hours in the room, and 9 hours standing. Show the rear. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 34, by leaving the bag that has been inflated to a medium level under the carbon dioxide at a high concentration, the bag expands to about 1.5 times the volume after being allowed to stand for 5 hours. Became. Thereafter, the volume of the bag decreased after being left in the room for 4 hours, and after being left in the room for 2 hours, it became about 1.2 times the volume immediately after the expansion. Moreover, after being left still in the room for 9 hours, the volume became almost the same as the volume immediately after the expansion. This result showed that the polyurethane bag selectively allows carbon dioxide to pass through, but does not allow substances other than carbon dioxide (eg, oxygen and nitrogen) to pass through.

Next, it was confirmed that polyethylene permeates carbon dioxide in liquid.

150 ml of carbon dioxide water (commercially available) was placed in a polyethylene bag (0.04 mm thick, commercially available. Hereinafter, the polyethylene bag is also referred to as a plastic bag). The bag was inserted into a 450 ml wide-mouthed glass bottle, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 10 minutes, 30 minutes, 1 hour, 2 hours, and 3 hours. After the glass bottle was allowed to stand still, the carbon dioxide concentration of the gas in the area between the wall of the glass bottle and the bag was measured.

The results are shown in FIG. 17. FIG. 17 is a graph showing the carbon dioxide concentration. In FIG. 17, the vertical axis shows carbon dioxide concentration (%), and the horizontal axis shows 10 minutes, 30 minutes, 1 hour, 2 hours, and 3 hours from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 17, the carbon dioxide concentration increased almost over time. Note that no water (liquid) was observed to be released from the bag. From this, it can be seen that carbon dioxide from the liquid carbon dioxide water permeated through the bag and was released into the space inside the glass bottle.

Next, an experiment was conducted in the same manner except that the space between the wall of the glass bottle and the bag was filled with liquid instead of gas. 150 ml of the carbon dioxide water was placed in the polyethylene bag (thickness: 0.04 mm). The bag was inserted into a 450 ml wide-mouth glass bottle, water was filled to capacity between the wall of the glass bottle and the bag, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 14 hours. After the bag was allowed to stand still, the carbon dioxide concentration was calculated for the strongly carbonated water (inner liquid) in the bag and the liquid (outer liquid) in the area between the wall of the glass bottle and the bag. To calculate the carbon dioxide concentration, put 1.8 ml of each of the liquids into a test tube, and add a mixed solution containing 0.2 ml of a 1N NaOH aqueous solution and 2 ml of a 0.1 mol/l CaCl ₂ aqueous solution to the test tube. It was calculated indirectly by weighing the precipitate formed by the addition.

The results are shown in FIG. FIG. 18 is a graph showing the carbon dioxide concentration. In FIG. 18, the vertical axis indicates the weight (g/tube) of the precipitate, and the horizontal axis indicates, from the left, external fluid and internal fluid. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of 5 samples.

As shown in FIG. 18, a high concentration of carbon dioxide was detected not only in the carbon dioxide water (inner liquid) in the bag, but also in the liquid (outer liquid) in the area between the wall surface of the glass bottle and the bag. It was done. The results indicated that carbon dioxide was transferred between the liquids through the bag.

Next, using the polyethylene bag, it was confirmed that hydrogen permeates through the bag.

100% hydrogen was similarly injected into the polyethylene bag. The bag was sealed and left at room temperature for 5 and 10 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was measured.

The results are shown in FIG. 29. FIG. 29 is a graph showing the volume of the bag. In FIG. 29, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours and 10 hours from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 29, after standing still for 5 hours, the volume of the bag was significantly reduced compared to immediately after sealing, and the relative value of the volume was 0.7. Moreover, after standing still for 10 hours, the volume further decreased, and the relative value of the volume was 0.36. From this, it was found that the polyethylene bag permeates hydrogen. As mentioned above, when carbon dioxide is absorbed from the outside of the polyethylene bag, the relative value of the volume increases by 1.5 times after 5 hours of standing, confirming that the permeation rate is high. Ta. From this, it is thought that the permeation rate of carbon dioxide is faster than the permeation rate of hydrogen. From the above, it was shown that carbon dioxide can selectively permeate through the membrane.

Next, using the polyethylene bag, it was confirmed that the bag slightly permeated methane.

100% methane (manufactured by As One) was similarly injected into the polyethylene bag. The bag was sealed and left at room temperature for 5, 10, and 15 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was measured.

The results are shown in FIG. 30. FIG. 30 is a graph showing the volume of the bag. In FIG. 30, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours, 10 hours, and 15 hours from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As a result, after standing still for 5 hours, the volume of the bag did not change compared to immediately after the sealing, and the relative value of the volume was 1.0. Moreover, even after standing still for 10 hours, the relative value of the volume was 0.99. Moreover, after standing still for 15 hours, the volume decreased slightly, and the relative value of the volume was 0.83. From this, it was found that the polyethylene bag slightly permeates methane. As mentioned above, when carbon dioxide is absorbed from the outside of the polyethylene bag, the relative value of the volume increases by 1.5 times after 5 hours of standing, confirming that the permeation rate is high. Ta. From this, it is thought that the permeation rate of carbon dioxide is faster than the permeation rate of methane. From the above, it was shown that carbon dioxide can selectively permeate through the membrane.

Next, using the polyethylene bag, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase.

100% hydrogen was similarly injected into the polyethylene bag. After the bag was placed in a wide-mouth glass bottle with a volume of 450 ml, water was filled to the full capacity between the wall of the glass bottle and the bag, and the bottle was sealed with a lid. Further, after filling the bag with water in the same manner, the bag was left submerged in the water without covering it. Each of these was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was calculated in the same manner.

As a result, the relative value of the volume compared to the volume immediately after the sealing is 1 even after the 24-hour standing period in both the cases where the lid is placed and the case where the lid is not placed. The deviation was approximately 0. From this, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase in the polyethylene bag.

Next, using the polyethylene bag, it was confirmed that methane did not permeate from the gas phase to the liquid phase.

100% methane (manufactured by As One) was similarly injected into the polyethylene bag. After the bag was placed in a wide-mouth glass bottle with a volume of 450 ml, water was filled to the full capacity between the wall of the glass bottle and the bag, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was calculated in the same manner.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that methane did not permeate from the gas phase to the liquid phase in the polyethylene bag.

As described above, it was confirmed that polyethylene permeates carbon dioxide in the liquid. Furthermore, it was confirmed that by using a polyethylene membrane and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.

[Example 5]
It was confirmed that carbon dioxide can be selectively permeated using a cellulose membrane. In addition, the cellulose membrane allows hydrogen and methane to permeate, and by using the cellulose membrane and water, it is possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane. It was confirmed.

A visking tube (cellulose dialysis membrane) (manufactured by Sanko Junyaku Co., Ltd.) with both ends closed was filled with 60 ml of 100% carbon dioxide. The Visking tube was sealed and allowed to stand at room temperature for 10, 20, and 30 minutes. Immediately after the sealing and after the standing, the volume of the Visking tube was calculated in the same manner as in Example 2.

The results are shown in FIG. 19. FIG. 19 is a graph showing the volume of the Visking tube. In FIG. 19, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates, from the left, immediately after the sealing (0), 30 minutes, and 60 minutes. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 19, the volume decreased to about 25% after being allowed to stand for 30 minutes, and decreased to several % after being allowed to stand for 60 minutes. This indicates that carbon dioxide is released extremely quickly through the Visking tube.

Next, the concentration of carbon dioxide released from the Visking tube was measured. 60 ml of 100% carbon dioxide was filled into the Visking tube closed at both ends. The Visking tube was sealed, placed in a 450 ml glass bottle, and left to stand at room temperature for 10 and 20 minutes. After the glass bottle was allowed to stand still, the carbon dioxide concentration of the gas in the area between the wall surface of the glass bottle and the Visking tube was measured.

The results are shown in FIG. 20. FIG. 20 is a graph showing the carbon dioxide concentration. In FIG. 20, the vertical axis shows the carbon dioxide concentration (%), and the horizontal axis shows, from the left, immediately after sealing (0), 10 minutes, and 20 minutes. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 20, the carbon dioxide concentration in the glass bottle became high after it was left standing for 10 minutes, and further increased after 20 minutes.

Next, it was confirmed that the Visking tube allows carbon dioxide to permeate from the outside to the inside. After putting 30 ml of air into the Visking tube and sealing it, and putting the Visking tube into a glass bottle with a volume of 4 L, 80% carbon dioxide was poured into the area between the wall of the glass bottle and the Visking tube. Filled. This was allowed to stand at room temperature for 1 hour (1 hour absorption). Thereafter, it was allowed to stand indoors for 1 hour and 2 hours (1 hour release and 2 hour release). After the above-mentioned standing still, the volume of the above-mentioned Visking tube was measured.

The results are shown in FIG. 21. FIG. 21 is a graph showing the volume of the sealed Visking tube. In FIG. 21, the vertical axis shows the relative value of the volume immediately after the sealing, and the horizontal axis shows, from the left, after 1 hour of standing (1h absorption), 1 hour, and 2 hours of room standing ( 1h release and 2h release). Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 21, the volume of the Visking tube after being allowed to stand for 1 hour (1 hour absorption) was about 2.3 times that of the volume immediately after sealing. When the Visking tube was left in a room, its volume rapidly decreased and returned to its original volume after 1 hour (1 hour release). Furthermore, no further decrease in volume was observed upon further standing (2 h release). This indicates that the Visking tube selectively allows carbon dioxide to pass through (absorb and release).

Next, it was confirmed that carbon dioxide between liquids permeated through the Visking tube. 60 ml of the carbon dioxide water was placed in the Visking tube. The Visking tube was inserted into a wide-mouth glass bottle with a volume of 450 ml, water was filled to the full capacity between the wall of the glass bottle and the Visking tube, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 5 hours. After the standing, the carbon dioxide concentration was calculated for the strongly carbonated water (inner liquid) in the Visking tube and the liquid (external liquid) in the portion between the wall surface of the glass bottle and the Visking tube. . To calculate the carbon dioxide concentration, put 1.8 ml of each of the liquids into a test tube, and add a mixed solution containing 0.2 ml of a 1N NaOH aqueous solution and 2 ml of a 0.1 mol/l CaCl ₂ aqueous solution to the test tube. and weighing the precipitate formed by said addition.

The results are shown in FIG. 23. FIG. 23 is a graph showing the carbon dioxide concentration. In FIG. 23, the vertical axis indicates the weight (g/tube) of the precipitate, and the horizontal axis indicates, from the left, an external solution (Outside) and an internal solution (Inside). Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 23, not only the strongly carbonated water (internal liquid) in the Visking tube, but also the liquid (external liquid) between the wall surface of the glass bottle and the Visking tube have high levels of carbon dioxide. Carbon concentration was detected. This result indicated that carbon dioxide was transferred between the liquids via the Visking tube.

Next, using the Visking tube, it was confirmed that the hydrogen permeation rate was slower than the carbon dioxide permeation rate.

34-50 ml of 100% hydrogen was placed in the Visking tube and sealed. The Visking tube was inserted into a wide-mouthed glass bottle with a volume of 450 ml, and the bottle was further sealed with a lid. This was allowed to stand at room temperature for 4, 8, and 12 hours. Further, in the same manner, it was allowed to stand at room temperature for 5 and 10 hours. Immediately after the sealing and after the standing, the volume of the Visking tube was calculated in the same manner as in Example 2.

The results are shown in FIGS. 24(A) and 24(B). 24 and (B) are graphs showing the volume of the Visking tube. In FIG. 24(A), the vertical axis indicates the relative value of the volume, and the horizontal axis indicates 4, 8, and 12 hours from the left. Note that the volume value was the average value of the measured values of a total of four samples. In FIG. 24(B), the vertical axis indicates the relative value of the volume, and the horizontal axis indicates 5 and 10 hours from the left. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 24(A), after the 4 hours of standing, the volume decreased to about 60%. In addition, after the above-mentioned standing for 8 hours and 12 hours, it decreased to 40% and 32%, respectively. The results in FIG. 24(B) were also similar. As mentioned above, when a similar experiment was conducted using carbon dioxide, the volume decreased to about 25% after the 30 minutes of standing. This showed that the release of hydrogen by the Visking tube was slower than the release of carbon dioxide.

Here, since hydrogen has a small molecular size, it can be said that it can easily permeate through the membrane from the viewpoint of molecular sieves. Despite this, the results showed that the carbon dioxide permeation rate was faster compared to the hydrogen permeation rate. From the above, it was shown that carbon dioxide can selectively permeate through the membrane.

Next, using the Visking tube, it was confirmed that the permeation rate of methane was slower than the permeation rate of carbon dioxide.

34 to 50 ml of 100% methane (manufactured by As One) was placed in the Visking tube and sealed. The Visking tube was inserted into a wide-mouthed glass bottle with a volume of 450 ml, and the bottle was further sealed with a lid. This was allowed to stand at room temperature for 5, 10, and 15 hours. Immediately after the sealing and after the standing, the volume of the Visking tube was calculated in the same manner.

The results are shown in FIG. 27. FIG. 27 is a graph showing the volume of the Visking tube. In FIG. 27, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates 5, 10, and 15 hours from the left. Note that the volume value was the average value of the measured values of a total of four samples.

As shown in FIG. 27, after the 5 hours of standing, the volume hardly decreased, and the relative value of the volume was 0.97. Further, the values were also 0.86 and 0.77 after the above-mentioned standing for 10 hours and 15 hours, respectively. As mentioned above, when a similar experiment was conducted using carbon dioxide, the volume decreased to about 25% after the 30 minutes of standing. This indicated that the release of methane through the Visking tube was slow compared to the release of carbon dioxide.

Here, since the molecular size of methane is smaller than that of carbon dioxide, it can be said that it can easily pass through the membrane from the viewpoint of a molecular sieve. Despite this, the results showed that the permeation rate of carbon dioxide was faster compared to the permeation rate of methane. From the above, it was shown that carbon dioxide can selectively permeate through the membrane.

Next, using the Visking tube, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase.

100% hydrogen was similarly placed in the Visking tube and sealed. The Visking tube was placed in a wide-mouthed glass bottle with a volume of 450 ml, and then water was filled to the full capacity between the wall of the glass bottle and the Visking tube, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the standing, the volume of the Visking tube was calculated in the same manner as in Example 2.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase in the cellulose bag.

Next, using the Visking tube, it was confirmed that methane did not permeate from the gas phase to the liquid phase.

Similarly, 100% methane (manufactured by As One) was placed in the Visking tube and sealed. The Visking tube was placed in a wide-mouthed glass bottle with a volume of 450 ml, and then water was filled to the full capacity between the wall of the glass bottle and the Visking tube, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the standing, the volume of the Visking tube was calculated in the same manner as in Example 2.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that methane did not permeate from the gas phase to the liquid phase in the cellulose bag.

As described above, it was confirmed that carbon dioxide can be selectively permeated using a cellulose membrane. In addition, the cellulose membrane allows hydrogen and methane to permeate, and by using the cellulose membrane and water, it is possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane. I was able to confirm.

[Example 6]
It was confirmed that polyurethane selectively permeates carbon dioxide. Furthermore, it was confirmed that by using a polyurethane bag and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.

A polyurethane bag (0.02 mm thick, commercially available) was moderately inflated with human exhalation. The bag was sealed and placed in a 4 liter glass bottle filled with 80% carbon dioxide, and left to stand for 2 hours. Thereafter, the bag was taken out of the glass bottle and left indoors for 1, 2, and 4 hours. The volume of the bag was calculated in the same manner as in Example 2 immediately after the expansion, after being left still under carbon dioxide, and after being left still in the room.

The results are shown in FIG. 31. FIG. 31 is a graph showing the volume of the bag. In FIG. 31, the vertical axis shows the relative value of the volume, and the horizontal axis shows, from the left, immediately after the expansion, after standing under the carbon dioxide, and for 1, 2, and 4 hours in the room. Shown after being left still. Note that the volume value was the average value of the measured values of three samples in total.

As shown in FIG. 31, by leaving the bag inflated to a medium level under the carbon dioxide at a high concentration, the bag expands to about 2.3 times the volume after being left for 2 hours. Became. Thereafter, the volume of the bag decreased after being left in the room for 1 hour, and after being left in the room for 2 hours, the volume became approximately the same (1.05) as the volume immediately after the expansion. Further, even after being left still in the room for 4 hours, the volume remained the same as that immediately after the expansion. This result showed that the polyurethane bag selectively allows carbon dioxide to pass through, but does not allow substances other than carbon dioxide (eg, oxygen and nitrogen) to pass through.

Next, using the polyurethane bag, it was confirmed that hydrogen permeates through the bag and that the hydrogen permeation rate is slower than the carbon dioxide permeation rate.

100% hydrogen was similarly injected into the polyurethane bag. The bag was sealed and left at room temperature for 5 and 10 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was measured.

The results are shown in FIG. 32. FIG. 32 is a graph showing the volume of the bag. In FIG. 32, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours and 10 hours from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 32, after standing still for 5 hours, the volume of the bag significantly decreased compared to immediately after sealing, and the relative value of the volume was 0.47. Moreover, after standing still for 10 hours, the volume decreased further, and the relative value of the volume was 0.26. From this, it was found that the polyurethane bag permeates hydrogen. As mentioned above, by leaving the bag, which has expanded approximately 2.3 times due to the high concentration of carbon dioxide, in a room for 2 hours, the volume will be the same as that before expansion due to the high concentration of carbon dioxide. (1.05). That is, the relative value of the volume was 1.05÷2.3=0.46. From this, it was found that the permeation rate of carbon dioxide was faster than the permeation rate of hydrogen. From the above, it was shown that carbon dioxide can selectively permeate the bag.

Next, using the polyurethane bag, it was confirmed that methane permeates through the bag and that the permeation rate of methane is slower than the permeation rate of carbon dioxide.

100% methane (manufactured by As One) was similarly injected into the polyurethane bag. The bag was sealed and left at room temperature for 5, 10, and 15 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was measured.

The results are shown in FIG. 33. FIG. 33 is a graph showing the volume of the bag. In FIG. 33, the vertical axis indicates the relative value of the volume, and the horizontal axis indicates the 5 hours, 10 hours, and 15 hours from the left. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As a result, after standing still for 5 hours, the volume of the bag decreased compared to immediately after sealing, and the relative value of the volume was 0.76. Moreover, after standing still for 10 hours, the volume further decreased, and the relative value of the volume was 0.6. Moreover, after standing still for 15 hours, the volume further decreased, and the relative value of the volume was 0.39. From this, it was found that the polyethylene bag permeates methane. As mentioned above, by leaving the bag, which has expanded approximately 2.3 times due to the high concentration of carbon dioxide, in a room for 2 hours, the volume will be the same as that before expansion due to the high concentration of carbon dioxide. (1.05). That is, the relative value of the volume was 1.05÷2.3=0.46. From this, it was found that the permeation rate of carbon dioxide was faster than that of methane. From the above, it was shown that carbon dioxide can selectively permeate the bag.

Next, using the polyurethane bag, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase.

100% hydrogen was similarly injected into the polyurethane bag. After the bag was placed in a wide-mouth glass bottle with a volume of 450 ml, water was filled to the full capacity between the wall of the glass bottle and the bag, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was calculated in the same manner.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that hydrogen did not permeate from the gas phase to the liquid phase in the polyurethane bag.

Next, using the polyurethane bag, it was confirmed that methane did not permeate from the gas phase to the liquid phase.

100% methane (manufactured by As One) was similarly injected into the polyurethane bag. After the bag was placed in a wide-mouth glass bottle with a volume of 450 ml, water was filled to the full capacity between the wall of the glass bottle and the bag, and the bottle was sealed with a lid. This was allowed to stand at room temperature for 24 hours. Immediately after the sealing and after the bag was allowed to stand, the volume of the bag was calculated in the same manner.

As a result, even after 24 hours of standing, the relative value of the volume compared to the volume immediately after sealing was 1, and the standard deviation was about 0. From this, it was confirmed that methane did not permeate from the gas phase to the liquid phase in the polyurethane bag.

As described above, it was confirmed that polyurethane selectively permeates carbon dioxide. Furthermore, it was confirmed that by using a polyurethane bag and water, it was possible to separate each gas in a mixed gas of carbon dioxide, hydrogen, and methane.
[Example 7]
Using a carbon dioxide permeable agent having a bubble structure, we confirmed that the volume of the carbon dioxide permeable agent changes by permeating carbon dioxide into the bubble structure.

As a carbon dioxide absorbent, foam packaging material (bubble wrap) (made of polyethylene, size: 10 x 60 cm, commercially available) was used. Two types of foam packaging materials were used: one with a double structure provided with a cover covering the bubble structure (Babble Wrap II), and one without a cover covering the bubble structure (Babble Wrap I). Each of the foamed packaging materials was washed with tap water and then rolled up and placed in a 300 ml wide-mouthed glass bottle with a lid (commercially available). Then, strongly carbonated water (commercially available) was poured into the glass bottle to its full capacity, the bottle was sealed, and the bottle was allowed to stand at room temperature for 5 hours. Thereafter, with the foamed packaging material in it, the glass bottle was filled with tap water to its full capacity and immediately removed, thereby washing the bottle three times in total. Furthermore, after washing the container three times, the container is sealed and left in a thermostat heated to 50°C for 5 hours, and then left to stand at room temperature, and when the temperature inside the container reaches room temperature. , carbon dioxide concentration was measured.

Further, an experiment was conducted in the same manner except that the glass bottle was filled with 100% carbon dioxide instead of the strongly carbonated water.

These results are shown in FIG. FIG. 9 is a graph showing the carbon dioxide concentration. In FIG. 9, the vertical axis shows the carbon dioxide concentration (%), and on the horizontal axis, the left side is the foam packaging material without the cover (Babble Wrap I), and the right side is the foam packaging material with the double structure (Babble Wrap I). Wrap II). The white graph shows the results for strongly carbonated water, and the black graph shows the results for 100% carbon dioxide. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 9, a significant release of carbon dioxide was observed in the two types of foam packaging materials, both when strongly carbonated water was used and when 100% carbon dioxide was used.

Next, changes in the volume of the carbon dioxide absorbent due to the above experiment were measured. First, in the same manner as in the above experiment, the foam packaging material (Babble Wrap II) was used as the carbon dioxide absorbent, and after being treated with strong carbonated water at room temperature for 5 hours, it was washed three times. I did it. After the washing, the glass bottle containing the foam packaging material was filled with water to its full capacity. The volume of the water was measured by transferring the entire amount of the water to a graduated cylinder. In addition, the glass bottle without the foam packaging material was filled with water to its full capacity, and the volume of the water was measured in the same manner. Then, by subtracting the volume of the water in the glass bottle containing the foam packaging material after absorption of carbon dioxide from the volume of the water in the glass bottle without the foam packaging material, The volume of the foam packaging material was calculated. Next, in the same manner as in the experiment described above, the glass bottle containing the foamed packaging material after absorption of carbon dioxide was heated at 50° C. for 5 hours, and then heat was radiated. After the heat dissipation, the glass bottle and the foam packaging material were similarly washed three times with tap water. After the washing, the glass bottle containing the foamed packaging material was filled with water, and the volume of the water was measured in the same manner. Then, by subtracting the volume of the water in the glass bottle containing the foam packaging material after the release of carbon dioxide from the volume of the water in the glass bottle without the foam packaging material, The volume of the foam packaging material was calculated.

Then, by subtracting the volume of the foam packaging material after releasing the carbon dioxide from the volume of the foam packaging material after absorbing the carbon dioxide, the volume of the carbon dioxide absorbent due to the release of carbon dioxide is calculated. The amount of decrease was calculated.

These results are shown in FIG. FIG. 10 is a graph showing the amount of decrease in the volume of the carbon dioxide absorbent as carbon dioxide is released. In FIG. 10, the vertical axis indicates the amount of decrease (ml) in the volume of the carbon dioxide absorbent. Note that the value of the amount of decrease in volume was the average value of the measured values of a total of 8 samples.

As shown in FIG. 10, as carbon dioxide was released, the volume of the foam packaging material, which was the carbon dioxide absorbent, decreased by 65 ml. From this, as carbon dioxide is absorbed into the bubble structure, the volume of the carbon dioxide absorbent increases, and as carbon dioxide is released from the bubble structure, the increased volume of the carbon dioxide absorbent decreases. It is thought that then.

As described above, it was confirmed that by using a carbon dioxide permeable agent having a bubble structure, the volume of the carbon dioxide permeable agent changes by permeating carbon dioxide into the bubble structure.

[Reference example 1]
It was confirmed that carbon dioxide (CO ₂ ) was absorbed into the resin container and that carbon dioxide was released from the resin container that had absorbed carbon dioxide.

A polyethylene terephthalate container (PET bottle) (product name: Strong Carbonated Water, manufactured by Kimura Soft Drinks Co., Ltd.) containing 500 ml of strongly carbonated water was prepared. The container containing the strongly carbonated water was a commercially available container that had been left to stand for at least one day after being purchased.

Immediately after removing the strongly carbonated water from the container, the carbon dioxide concentration in the container was measured. To measure the carbon dioxide concentration, a gas outlet is provided on the lid of the container, and a carbon dioxide detector (XP-3140, manufactured by COSMO) (for low concentration) and (CX-6000, manufactured by RIKEN KEIKI) are used. (for high concentration) was used to measure the carbon dioxide concentration in the gas at the outlet. As a result, the carbon dioxide concentration in the container immediately after the strongly carbonated water was removed was as high as 20.8% (average value of the measured values of a total of 6 samples). Note that the carbon dioxide concentration can be converted as 1%=10,000ppm.

Next, the container was washed by filling the container to its full capacity with tap water and immediately removing it. This was regarded as one wash, and a total of three washes were performed (1st Wash to 3rd Wash). Carbon dioxide concentration was similarly measured immediately after each wash.

Furthermore, after washing the container three times, the container is sealed and left in a thermostat heated to 50°C for 5 hours, and then left to stand at room temperature, and when the temperature inside the container reaches room temperature. , Carbon dioxide concentration was measured in the same manner.

These results are shown in FIG. 22. FIG. 22 is a graph showing the carbon dioxide concentration. In FIG. 22, the vertical axis shows the carbon dioxide concentration (PPM), and the horizontal axis shows, from the left, after the first to third washes (1st Wash to 3rd Wash) and after the heating. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of six samples.

As shown in FIG. 22, after the first washing, 4027 ppm of carbon dioxide remained. The remaining carbon dioxide was significantly reduced by the second and third washings. Further, after the heating, 6800 ppm of carbon dioxide was measured. From this, it was confirmed that the carbon dioxide absorbed in the container was released by the heating.

Next, an experiment was conducted by changing the heating conditions. After washing three times, the container was placed in a constant temperature device at 50°C or 20°C for 1 hour, 2 hours, 6 hours, and 24 hours, and then left at room temperature until the temperature inside the container was lowered. When the temperature reached room temperature, the carbon dioxide concentration was measured in the same manner.

The results are shown in FIG. 35. FIG. 35 is a graph showing the carbon dioxide concentration. In FIG. 35, the vertical axis shows the carbon dioxide concentration (%), and the horizontal axis shows the results after standing for 1 hour, 2 hours, 6 hours, and 24 hours from the left. The white graph shows the results at 50°C, and the black graph shows the results at 20°C. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of four samples.

As shown in FIG. 35, both the 50° C. and 20° C. treatments increased the carbon dioxide concentration in the container over time. From this, it was confirmed that the carbon dioxide absorbed in the container was released even by the treatment at 20°C. Furthermore, more carbon dioxide was released by the treatment at 50°C than by the treatment at 20°C. From this, it was confirmed that more carbon dioxide absorbed in the container was released by the heating.

As described above, it was confirmed that carbon dioxide is absorbed into the resin container and that carbon dioxide is released from the resin container that has absorbed carbon dioxide.

[Reference example 2]
Using resin containers made of different materials, it was confirmed that carbon dioxide was released from the resin containers that had absorbed carbon dioxide.

Different resin containers with a capacity of 250 ml or 500 ml were prepared. The resins include high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polytetrafluoroethylene (PTFE), and polycarbonate (PC) (all manufactured by As One), and polyethylene terephthalate ( PET) (reused plastic bottles of commercially available non-carbonated drinks).

Strongly carbonated water (commercially available) was poured into each of the containers to the full, the containers were sealed, and the containers were allowed to stand at room temperature for 5 hours. Thereafter, washing was performed a total of three times in the same manner as in Reference Example 1. Furthermore, in the same manner as in Reference Example 1, after heating at 50° C. for 5 hours, heat was radiated, and the carbon dioxide concentration was measured.

Further, each of the containers was filled with 100% carbon dioxide by sufficiently introducing the container, and then sealed and allowed to stand at room temperature for 5 hours. Thereafter, washing was performed a total of three times in the same manner as in Reference Example 1. Furthermore, in the same manner as in Reference Example 1, after heating at 50° C. for 5 hours, heat was radiated, and the carbon dioxide concentration was measured.

These results are shown in FIG. 36. FIG. 36 is a graph showing the carbon dioxide concentration. In FIG. 36, the vertical axis shows carbon dioxide concentration (PPM), and the horizontal axis shows, from left to right, high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), and polytetrafluoroethylene (PTFE). , polycarbonate (PC), and polyethylene terephthalate (PET). The white graph shows the results for 100% carbon dioxide, and the black graph shows the results for strongly carbonated water. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of three samples.

As shown in FIG. 36, when strongly carbonated water was used, release of carbon dioxide was observed in all resins. High-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polytetrafluoroethylene (PTFE), and polycarbonate (PC) all contain more of carbon dioxide was observed. In particular, polycarbonate (PC) had a significantly increased carbon dioxide concentration.

Further, as shown in FIG. 36, even when 100% carbon dioxide was used, release of carbon dioxide was observed in all resins. High-density polyethylene (HDPE) was found to emit carbon dioxide to the same extent as polyethylene terephthalate (PET). Low-density polyethylene (LDPE), polypropylene (PP), polytetrafluoroethylene (PTFE), and polycarbonate (PC) all exhibit higher carbon dioxide emissions compared to polyethylene terephthalate (PET). It was done. In particular, polycarbonate (PC) had a significantly increased carbon dioxide concentration.

As described above, using resin containers made of different materials, it was confirmed that carbon dioxide was released from the resin containers that had absorbed carbon dioxide.

[Reference example 3]
Using different forms of carbon dioxide absorbents, it was confirmed that carbon dioxide was released from the carbon dioxide absorbents that absorbed carbon dioxide.

A polypropylene Spitz tube (manufactured by Eikensha) with a capacity of 10 ml was used as a carbon dioxide absorbent. The eight Spitz tubes were placed in a wide-mouth glass bottle with a lid (commercially available) with a capacity of 300 ml. Then, strongly carbonated water (commercially available) was poured into the glass bottle to its full capacity, the bottle was sealed, and the bottle was allowed to stand at room temperature for 5 hours. Thereafter, washing was performed a total of three times in the same manner as in Reference Example 1. Furthermore, in the same manner as in Reference Example 1, after heating at 50° C. for 5 hours, heat was radiated, and the carbon dioxide concentration was measured.

Further, an experiment was conducted in the same manner except that strong carbonated water manufactured by another company was used instead of the above-mentioned strongly carbonated water. In addition, an experiment was conducted in the same manner except that instead of standing at room temperature, it was left standing at 4°C. Further, an experiment was conducted in the same manner except that the glass bottle was filled with 100% carbon dioxide instead of the strongly carbonated water.

These results are shown in FIG. FIG. 7 is a graph showing the carbon dioxide concentration. In FIG. 7, the vertical axis shows the carbon dioxide concentration (%), and the horizontal axis shows, from the left, 100% carbon dioxide (CO ₂ ), strongly carbonated water (SBWater 20°C), and strongly carbonated water (SBWater 20°C) at 4°C. SBWater (4℃) and strong carbonated water (Gerolsteiner) made by another company. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of 3 to 4 samples.

As shown in Figure 7, when using strongly carbonated water (SBWater 20°C), strongly carbonated water at 4°C (SBWater 4°C), and strongly carbonated water made by another company (Gerolsteiner), the results were similar. Carbon dioxide emissions were observed. Also, when 100% carbon dioxide (CO ₂ ) was used, carbon dioxide was released, although the amount was smaller than when using strongly carbonated water.

Next, a rubber plate (striped, size: 3 x 100 x 100 mm, manufactured by HIKARI Co., Ltd.) was used as a carbon dioxide absorbent (Rubber II). The rubber plate was placed in a wide-mouth glass bottle (commercially available) with a lid having a capacity of 300 ml. Then, strongly carbonated water (commercially available) was poured into the glass bottle to its full capacity, the bottle was sealed, and the bottle was allowed to stand at room temperature (24° C.) for 5 hours. Thereafter, washing was performed a total of three times in the same manner as in Reference Example 1. Furthermore, in the same manner as in Reference Example 1, after heating at 50° C. for 5 hours, heat was radiated, and the carbon dioxide concentration was measured.

In addition, as a carbon dioxide absorbent, instead of the rubber plate mentioned above, a rubber plate without streak structure (size: 1x100x100mm, manufactured by HIKARI Co., Ltd.) (Rubber I), an acrylic rod (major diameter 6 mm, length 170 mm), mm), polyethylene mesh (size: 92-#18, manufactured by As One Corporation), and nylon mesh (size: 63 μ, PA-2, manufactured by As One Corporation) were used in the same manner, We conducted an experiment.

Further, for each of the carbon dioxide absorbents, an experiment was conducted in the same manner except that the glass bottle was filled with 100% carbon dioxide instead of the strongly carbonated water.

These results are shown in FIG. FIG. 8 is a graph showing the carbon dioxide concentration. In Figure 8, the vertical axis shows the carbon dioxide concentration (%), and the horizontal axis shows, from the left, rubber plate (with streaks) (Rubber I), rubber plate (without streaks) (Rubber II), acrylic rod (Acryl Shown are mesh rods, polyethylene mesh, and nylon mesh. The white graph shows the results for 100% carbon dioxide, and the black graph shows the results for strongly carbonated water. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of 3 to 4 samples.

As shown in FIG. 8, release of carbon dioxide was observed in all carbon dioxide absorbents, both when strongly carbonated water was used and when 100% carbon dioxide was used. In particular, when the carbon dioxide absorbent was a rubber plate (with streaks) and 100% carbon dioxide was used, the carbon dioxide concentration increased significantly.

As described above, it was confirmed that carbon dioxide is released from the carbon dioxide absorbent that has absorbed carbon dioxide using different forms of carbon dioxide absorbent.

[Reference example 4]
It was confirmed that the gas released from the carbon dioxide absorbent that absorbed carbon dioxide was carbon dioxide.

A container made of resin (polyethylene terephthalate (PET)) with a capacity of 300 ml (reused from a commercially available PET bottle for a non-carbonated beverage) was prepared.

In the same manner as in Reference Example 2, strongly carbonated water was placed in the container to absorb carbon dioxide, then heated (for 5 hours or 30 minutes) and allowed to radiate heat, and the carbon dioxide concentration in the container was measured. As a result, the concentration of carbon dioxide was 27% (high concentration CO ₂ ) in the heating for 5 hours and 2.8% (low concentration CO ₂ ) in the heating for 30 minutes.

Thereafter, a mixed solution containing 10 ml of a 0.1N NaOH aqueous solution and 10 ml of a 0.1 mol/l CaCl ₂ aqueous solution was placed in each of the containers, and the mixture was shaken vigorously by hand for 30 seconds. It is known that a mixed solution containing a 0.1N NaOH aqueous solution and a 0.1 mol/l CaCl ₂ aqueous solution reacts with and absorbs carbon dioxide. Immediately after the shaking, the carbon dioxide concentration in the container was measured.

The results are shown in FIG. FIG. 11 is a graph showing the carbon dioxide concentration. In FIG. 11, the vertical axis shows carbon dioxide concentration (%), and on the horizontal axis, the left side shows high concentration carbon dioxide (high concentration CO ₂ ), and the right side shows low concentration carbon dioxide (low concentration CO ₂ ). . The white graph shows the state before the reaction with the mixed liquid, and the black graph shows the state after the reaction with the mixed liquid. Note that the value of the carbon dioxide concentration was the average value of the measured values of a total of six samples.

As shown in FIG. 11, in both high-concentration carbon dioxide and low-concentration carbon dioxide, the carbon dioxide concentration after the reaction with the mixed liquid decreased significantly compared to before the reaction with the mixed liquid. was. From this, it was chemically confirmed that the gas released from the carbon dioxide absorbent could react as carbon dioxide.

As described above, it was confirmed that the gas released from the carbon dioxide absorbent that absorbed carbon dioxide was carbon dioxide.

Although the present invention has been described above with reference to the embodiments and examples, the present invention is not limited to the above embodiments. The configuration and details of the present invention may be modified in various ways within the scope of the present invention by those skilled in the art.

<Additional notes>
Some or all of the above embodiments may be described as in the following additional notes, but are not limited to the following.
(Additional note 1)
Contains a thin polymer film,
A carbon dioxide permeation agent, wherein the thin film selectively permeates carbon dioxide.
(Additional note 2)
Supplementary Note 1, wherein the polymer includes at least one selected from the group consisting of cellulose, polyethylene terephthalate, high density polyethylene, low density polyethylene, polypropylene, polytetrafluoroethylene, polycarbonate, rubber, polyurethane, and acrylic. Carbon dioxide permeable agent.
(Additional note 3)
The carbon dioxide permeable agent according to appendix 1 or 2, wherein the thin film does not permeate oxygen and nitrogen.
(Additional note 4)
the thin film permeates the carbon dioxide in a heated state;
The carbon dioxide permeable agent according to any one of Supplementary Notes 1 to 3.
(Appendix 5)
The thin film is capable of separating carbon dioxide from a gas mixture containing carbon dioxide and at least one of hydrogen and methane by selectively permeating carbon dioxide.
The carbon dioxide permeable agent according to any one of Supplementary Notes 1 to 4.
(Appendix 6)
including a carbon dioxide supply section and a carbon dioxide permeation section,
The carbon dioxide supply unit supplies a carbon dioxide-containing substance to the carbon dioxide permeation unit,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
The carbon dioxide permeation unit selectively permeates carbon dioxide contained in the supplied carbon dioxide-containing substance,
The carbon dioxide permeation section includes the carbon dioxide permeation agent according to any one of Supplementary Notes 1 to 5.
Carbon dioxide permeation device.
(Appendix 7)
The carbon dioxide permeation section permeates the carbon dioxide in a heated state.
Carbon dioxide absorption device according to supplementary note 6.
(Appendix 8)
The carbon dioxide permeation section includes two compartments,
the two compartments are connected via the thin film of the carbon dioxide permeable agent;
The carbon dioxide-containing substance is supplied to one of the compartments from the carbon dioxide supply section,
The other compartment is filled with a liquid so as to be in contact with the thin film.
Carbon dioxide permeation device according to appendix 6 or 7.
(Appendix 9)
The carbon dioxide-containing substance is a mixed gas containing carbon dioxide and at least one of hydrogen and methane,
The thin film selectively permeates carbon dioxide, whereby carbon dioxide can be separated from the gas mixture supplied to the one compartment to the liquid filling the other compartment.
Carbon dioxide permeation device according to appendix 8.
(Appendix 10)
Including a carbon dioxide supply step and a carbon dioxide permeation step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide permeation step,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
The carbon dioxide permeation step selectively permeates carbon dioxide contained in the supplied carbon dioxide-containing substance using the carbon dioxide permeation agent according to any one of Supplementary Notes 1 to 5.
Carbon dioxide permeation method.
(Appendix 11)
The carbon dioxide permeation step involves permeating the carbon dioxide in a heated state.
Carbon dioxide absorption method according to appendix 10.
(Appendix 12)
The carbon dioxide permeation step includes permeating the carbon dioxide through a carbon dioxide permeation section;
The carbon dioxide permeable section includes the carbon dioxide permeable agent and two compartments,
the two compartments are connected via the thin film of the carbon dioxide permeable agent;
The carbon dioxide-containing substance is supplied to one of the compartments from the carbon dioxide supply section,
The other compartment is filled with a liquid so as to be in contact with the thin film.
Carbon dioxide permeation method according to appendix 10 or 11.
(Appendix 13)
The carbon dioxide-containing substance is a mixed gas containing carbon dioxide and at least one of hydrogen and methane,
In the carbon dioxide permeation step, the thin film selectively permeates carbon dioxide, thereby transferring carbon dioxide from the mixed gas supplied to the one compartment to the liquid filling the other compartment. To separate,
Carbon dioxide permeation method according to appendix 12.
(Appendix 14)
including a carbon dioxide absorption section;
The carbon dioxide absorption section includes the carbon dioxide permeation agent according to any one of claims 1 to 5,
The inside of the carbon dioxide absorption part is sealed via the carbon dioxide permeable agent,
The thin film of the carbon dioxide permeable agent selectively permeates carbon dioxide, whereby carbon dioxide is absorbed from the outside of the carbon dioxide absorption section into the inside.
Carbon dioxide absorption device.
(Appendix 15)
Including a carbon dioxide supply step and a carbon dioxide absorption step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide absorption step,
In the carbon dioxide absorption step, carbon dioxide is absorbed by a carbon dioxide absorption section,
The carbon dioxide absorption section includes the carbon dioxide permeation agent according to any one of Supplementary Notes 1 to 5,
The inside of the carbon dioxide absorption part is sealed via the carbon dioxide permeable agent,
The thin film of the carbon dioxide permeable agent selectively permeates carbon dioxide, whereby carbon dioxide is absorbed from the outside of the carbon dioxide absorption section into the inside.
Carbon dioxide absorption method.
(Appendix 16)
Contains polymers,
A carbon dioxide absorbent, wherein the polymer absorbs carbon dioxide.
(Appendix 17)
Supplementary note 16, wherein the polymer includes at least one selected from the group consisting of cellulose, polyethylene terephthalate, high density polyethylene, low density polyethylene, polypropylene, polytetrafluoroethylene, polycarbonate, rubber, polyurethane, and acrylic. Carbon dioxide absorbent.
(Appendix 18)
the polymer releases the absorbed carbon dioxide in a heated state;
Carbon dioxide absorbent according to appendix 16 or 17.
(Appendix 19)
The carbon dioxide absorbent according to appendix 18, wherein the heated state is a state heated to 50° C. or higher.
(Additional note 20)
including a carbon dioxide supply section and a carbon dioxide absorption section,
The carbon dioxide supply unit supplies a carbon dioxide-containing substance to the carbon dioxide absorption unit,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
The carbon dioxide absorption unit absorbs carbon dioxide contained in the supplied carbon dioxide-containing substance,
The carbon dioxide absorbing section includes the carbon dioxide absorbent according to any one of Supplementary Notes 16 to 19.
Carbon dioxide absorption device.
(Additional note 21)
the carbon dioxide absorption section is heatable;
The carbon dioxide absorption unit further releases the absorbed carbon dioxide in a heated state.
Carbon dioxide absorption device according to appendix 20.
(Additional note 22)
Including a carbon dioxide supply step and a carbon dioxide absorption step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to the carbon dioxide absorption step,
The carbon dioxide-containing substance is at least one of a gas and a liquid,
In the carbon dioxide absorption step, carbon dioxide contained in the supplied carbon dioxide-containing substance is absorbed by the carbon dioxide absorbent according to any one of Supplementary Notes 16 to 19.
Carbon dioxide absorption method.
(Additional note 23)
Furthermore, it includes a carbon dioxide release step,
The carbon dioxide releasing step releases the absorbed carbon dioxide while the carbon dioxide absorbent is heated.
Carbon dioxide absorption method according to appendix 22.

As described above, according to the present invention, a new carbon dioxide permeation agent can be provided.

1 Carbon dioxide permeation device 11 Carbon dioxide supply section 12 Carbon dioxide permeation section 121 Carbon dioxide permeation agent 2 Heating section 3 Carbon dioxide absorption device 31 Carbon dioxide supply section 32 Carbon dioxide absorption section 321 Carbon dioxide absorbent 33 Carbon dioxide release section 4 Heating Department

Claims (6)

including a carbon dioxide permeable agent, a carbon dioxide supply section, and a carbon dioxide permeation section,
The carbon dioxide permeable agent includes a thin polymer film,
The polymer includes at least one selected from the group consisting of rubber, polyethylene, cellulose, and polyurethane,
the thin film selectively permeates carbon dioxide;
The carbon dioxide supply unit supplies a carbon dioxide-containing substance to the carbon dioxide permeation unit,
The carbon dioxide-containing substance is a mixed gas containing carbon dioxide, hydrogen and methane,
The carbon dioxide permeation section includes two compartments,
the two compartments are connected via the thin film of the carbon dioxide permeable agent;
The carbon dioxide-containing substance is supplied to one of the compartments from the carbon dioxide supply section,
The other compartment is filled with a liquid so as to be in contact with the thin film,
The carbon dioxide permeation unit selectively permeates carbon dioxide through the thin film, so that carbon dioxide is transferred from the carbon dioxide-containing substance supplied to the one compartment to the liquid filling the other compartment. is separable,
Carbon dioxide permeation device. The carbon dioxide permeation section permeates the carbon dioxide in a heated state.
The carbon dioxide permeation device according to claim 1. The polymer includes at least one selected from the group consisting of rubber, polyethylene, and polyurethane,
the thin film is impermeable to oxygen and nitrogen;
The carbon dioxide permeation device according to claim 1 or 2. Including a carbon dioxide supply step and a carbon dioxide permeation step,
The carbon dioxide supply step supplies a carbon dioxide-containing substance to a carbon dioxide permeation section,
The carbon dioxide-containing substance is a mixed gas containing carbon dioxide, hydrogen and methane,
The carbon dioxide permeable section includes a carbon dioxide permeable agent and two compartments,
The carbon dioxide permeable agent includes a thin polymer film,
The polymer includes at least one selected from the group consisting of rubber, polyethylene, cellulose, and polyurethane,
the thin film selectively permeates carbon dioxide;
the two compartments are connected via the thin film of the carbon dioxide permeable agent;
The carbon dioxide-containing substance is supplied to one of the compartments from the carbon dioxide supply section,
The other compartment is filled with a liquid so as to be in contact with the thin film,
In the carbon dioxide permeation step, the thin film selectively permeates carbon dioxide, so that carbon dioxide is transferred from the carbon dioxide-containing substance supplied to the one compartment to the liquid filling the other compartment. to separate,
Carbon dioxide permeation method. The carbon dioxide permeation step involves permeating the carbon dioxide in a heated state.
The carbon dioxide permeation method according to claim 4. The polymer includes at least one selected from the group consisting of rubber, polyethylene, and polyurethane,
the thin film is impermeable to oxygen and nitrogen;
The carbon dioxide permeation method according to claim 4 or 5.

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