Carbon dioxide immobilization device and battery

Abstract

The invention discloses a carbon dioxide immobilization device and a battery. Provided is a carbon dioxide immobilization device capable of extracting energy while efficiently immobilizing carbon dioxide in the atmosphere. This carbon dioxide immobilization device is provided with an aqueous solution containing a water-soluble polymer compound and a positive / negative electrode material, and is capable of generating a carbonate derived from carbon dioxide after energizing the electrode material. It is preferable that the water-soluble polymer compound is a polyamine that has two or more amino groups in the molecule, has a weight-average molecular weight of 500-50,000 (inclusive), and does not have volatility.

Description

Technical Field

[0001] The present invention relates to a carbon dioxide fixation device and a battery comprising the carbon dioxide fixation device. Background Art

[0002] The technologies that aim to mitigate or reduce the increase in atmospheric carbon dioxide concentration are collectively referred to as negative emission systems. Negative emission systems currently under consideration include BECCS (a technology that recovers carbon dioxide emitted when biofuels are used and stores it underground) and DACCS (a technology that directly recovers carbon dioxide already in the atmosphere and stores it). However, both methods require energy input in the stage of transferring carbon dioxide from the atmosphere after recovery to before storage.

[0003] For example, Patent Document 1 discloses the following method as a means of fixing carbon dioxide in the atmosphere in the form of alkaline earth metal carbonates: an aqueous solution in which metal ions and polyamines are dissolved is prepared in advance, and the aqueous solution is exposed to the atmosphere to absorb (dissolve) carbon dioxide in the atmosphere and precipitate the carbon dioxide in the form of carbonates.

[0004] Patent Document 2 discloses a method in which a gas containing carbon dioxide gas is brought into contact with an aqueous alkanolamine solution in an absorption tower to absorb carbon dioxide gas, and then the carbon dioxide gas absorbing liquid is heated to desorb and recover the carbon dioxide gas in a desorption tower.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2010-194378

[0008] Patent Document 2: Japanese Patent Application Publication No. 2006-240966 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, in the existing studies, it is necessary to input energy when fixing carbon dioxide as described in Patent Documents 1 and 2, and no study has been conducted on how to extract the energy.

[0011] Therefore, an object of the present invention is to provide a carbon dioxide fixation device capable of efficiently fixing carbon dioxide in the atmosphere and extracting energy.

[0012] Means used to solve problems

[0013] As a result of the inventors' diligent research to solve the above-mentioned problems, they found that if a carbon dioxide fixation device is provided with an aqueous solution containing a water-soluble polymer compound and positive and negative electrode materials, and can generate carbonate from carbon dioxide after electricity is passed through the electrode materials, energy can be extracted when carbon dioxide is fixed. The present invention relates to a device completed based on these findings.

[0014] In the above-mentioned carbon dioxide fixation device, energy can be extracted while precipitating and fixing carbon dioxide in the atmosphere in the form of carbonate.

[0015] The water-soluble polymer compound is preferably a nonvolatile polyamine having two or more amino groups in the molecule and a weight average molecular weight of 500 to 50000. The water-soluble polymer compound having the above structure can efficiently absorb carbon dioxide and has excellent safety.

[0016] The concentration of the water-soluble polymer compound in the aqueous solution is preferably 1 mass ppm or more and less than 1000 mass ppm. The water-soluble polymer compound has the above structure, so that it can absorb carbon dioxide and has excellent safety.

[0017] The pH of the aqueous solution immediately after preparation is preferably 8.6 or more and 14 or less. When the pH is within the above range, absorption of carbon dioxide in the aqueous solution becomes easy.

[0018] In the carbon dioxide fixation device, it is preferred that the aqueous solution contains substantially no metal ions before power is supplied.

[0019] The carbon dioxide fixation device is preferably a carbon dioxide fixation device in which the liquid surface of the aqueous solution is in contact with the atmosphere. Since the aqueous solution has high safety, it can be directly exposed to the atmosphere.

[0020] It is preferred that the carbon dioxide fixation device is configured such that, before power is supplied, carbon dioxide in the atmosphere can be dissolved in the aqueous solution to a saturated concentration.

[0021] The negative electrode material preferably contains a metal element other than an alkali metal.

[0022] The negative electrode material preferably contains one or more metal elements selected from zinc, iron and magnesium.

[0023] The positive electrode material is preferably formed of a material having a higher standard Gibbs energy of formation than that of the negative electrode material.

[0024] The carbon dioxide fixation device is preferably capable of extracting electrical energy.

[0025] In the carbon dioxide fixation device, it is preferred that the pH of the aqueous solution be 5.8 or more and less than 8.6 in a state where power is supplied.

[0026] Furthermore, the present invention provides a battery comprising the above-mentioned carbon dioxide fixation device.

[0027] Effects of the Invention

[0028] The carbon dioxide fixation device of the present invention can efficiently fix carbon dioxide in the atmosphere and extract energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a photograph of one embodiment of the carbon dioxide fixation device of the present invention.

[0030] Figure 2 This is a diagram showing the transition of voltage in the carbon dioxide fixation device of Example 1.

[0031] Figure 3 This is a diagram showing the transition of the electric current in the carbon dioxide fixation device of Example 1.

[0032] Figure 4 This is a diagram showing the transition of voltage in the carbon dioxide fixation device of Example 2.

[0033] Figure 5 This is a diagram showing the transition of the electric current in the carbon dioxide fixation device of Example 2.

[0034] Figure 6 3 is a graph showing the change in voltage in the carbon dioxide fixation device of Comparative Example 1.

[0035] Figure 7 This is a diagram showing the transition of the electric current in the carbon dioxide fixation device of Comparative Example 1. DETAILED DESCRIPTION

[0036] [Carbon dioxide fixation device]

[0037] The carbon dioxide fixation device of the present invention at least comprises an aqueous solution containing a water-soluble polymer compound and positive and negative electrode materials. The aqueous solution can efficiently absorb carbon dioxide in the atmosphere and generate carbonate ions by containing the water-soluble polymer compound. In addition, for the carbon dioxide fixation device, by energizing the electrode material, carbon dioxide in the atmosphere can be fixed while taking out energy. Specifically, for the carbon dioxide fixation device, by connecting the positive and negative electrode materials to an external circuit, a circuit can be formed by the aqueous solution and energized, and energy can be taken out in the form of energy through an LED or the like provided in the external circuit. Furthermore, when power is applied to the external circuit, the carbon dioxide in the atmosphere absorbed in the aqueous solution reacts, so that carbonate from the carbon dioxide in the atmosphere can be generated and fixed. It should be noted that in the present invention, if "atmosphere" includes air and carbon dioxide present in an open system, it also includes gases such as exhaust gas.

[0038] Therefore, the carbon dioxide fixation device can fix carbon dioxide in the atmosphere and extract energy. That is, the carbon dioxide fixation device can be used as a negative emission system that fixes and recovers carbon dioxide in the atmosphere and can also extract energy.

[0039] It should be noted that, in the present invention, situations not specifically mentioned are represented as states before power is supplied.

[0040] In addition, the carbon dioxide fixation device is preferably provided with a separator to separate the positive electrode material from the negative electrode material. By providing the separator, it is easy to use as a battery. As the separator, a known separator used for a battery can be used, and although there is no particular limitation, a separator made of resin is preferably used.

[0041] (Aqueous solution containing a water-soluble polymer compound)

[0042] The carbon dioxide fixation device includes an aqueous solution containing a water-soluble polymer compound (hereinafter referred to as "aqueous solution" or "electrolyte"). The aqueous solution contains the water-soluble polymer compound and can efficiently absorb carbon dioxide in the atmosphere in the form of carbonate ions. As the water-soluble polymer compound in the aqueous solution, only one type may be used, or two or more types may be used.

[0043] The water-soluble polymer compound is preferably a water-soluble polymer compound containing a nitrogen atom, and more preferably a polyamine and / or a salt thereof.

[0044] The weight average molecular weight of above-mentioned water-soluble polymer compound is preferably more than 500 and less than 150000, more preferably more than 1000 and less than 100000, further preferably more than 1500 and less than 50000.In addition, as upper limit, particularly preferably less than 40000, can also be less than 30000, less than 20000 or less than 15000.By making weight average molecular weight be more than 500, can make it nonvolatile, by making weight average molecular weight be less than 150000, because of above-mentioned water-soluble polymer compound and dissolved carbon dioxide, the hydrophobicity of the whole molecule generated by carboxylate or ester of above-mentioned water-soluble polymer compound rises, thus, above-mentioned water-soluble polymer compound breaks away from aqueous solution as precipitate, thus can suppress the carbon dioxide attraction ability decay in atmosphere.It should be noted that above-mentioned weight average molecular weight can be measured by following conditions for example.

[0045] Apparatus: Gel Permeation Chromatography GPC (machine name "No. GPC-31")

[0046] Detector: Differential refractive index detector RI (RI-501 manufactured by Showa Denko K.K., sensitivity 32)

[0047] Column: 1 TSKgel G6000PWXL-CP, 1 G3000PWXL-CP (7.8mm×30cm, manufactured by ToSoh Co., Ltd.)

[0048] Solvent: 0.1M acetate buffer (pH 4)

[0049] Flow rate: 0.7mL / min

[0050] Column temperature: 40°C

[0051] Injection volume: 0.2mL

[0052] Standard sample: Monodisperse polyethylene oxide (PEO) and polyethylene glycol (PEG) manufactured by Tosoh Corporation and Agilent

[0053] Data processing: GPC data processing system made by TRC

[0054] The water-soluble polymer compound is preferably a compound having more than two amino groups in the molecule, more preferably a compound having more than three amino groups, and further preferably a compound having more than four amino groups. The water-soluble polymer compound easily forms a carbamate compound with carbon dioxide in the atmosphere by having more than two amino groups in the molecule, thereby being able to efficiently absorb carbon dioxide in the atmosphere into the aqueous solution. In addition, the spontaneous hydrolysis of the generated carbamate can be induced, thereby promoting the generation of carbonate ions in the aqueous solution.

[0055] In addition, the above-mentioned water-soluble polymer compound is preferably a non-volatile compound. By making the above-mentioned water-soluble polymer compound non-volatile, excellent safety can be achieved even when the above-mentioned aqueous solution is in contact with the atmosphere. It should be noted that in the present invention, non-volatile means a compound that is non-volatile under normal temperature (25 °C) and normal pressure (1 atmospheric pressure) conditions.

[0056] The content of the above-mentioned water-soluble polymer compound in the above-mentioned aqueous solution is preferably 1 mass ppm or more and less than 1000 mass ppm, more preferably 3 mass ppm or more and 900 mass ppm or less, further preferably 5 mass ppm or more and 800 mass ppm or less, particularly preferably 10 mass ppm or more and 700 mass ppm or less, and most preferably 15 mass ppm or more and 600 mass ppm or less, based on 100 mass% of the above-mentioned aqueous solution. By making the above-mentioned content 1 mass ppm or more, carbon dioxide can be easily absorbed. By being less than 1000 mass ppm, sufficient safety is achieved and wastewater treatment becomes easy.

[0057] <Polyamine>

[0058] The amino group possessed by the above-mentioned polyamine can be an amino group constituting any of primary amine, secondary amine, and tertiary amine.

[0059] As the above-mentioned polyamine, for example, the polyamine represented by the following formula (1) can be cited.

[0060] ◎

Chemical Formula 1

[0061]

[0062] (In the formula, m represents an integer from 0 to 1000, and R 1 , R 2 each independently represents a linear or branched alkylene group having 2 to 8 carbon atoms. When m is 2 or more, a plurality of R 1 can be the same or different.)

[0063] The above-mentioned R 1 , R 2 each preferably represents a linear or branched alkylene group having 2 to 6 carbon atoms, and more preferably represents a linear or branched alkylene group having 3 to 5 carbon atoms.

[0064] The above-mentioned m more preferably represents an integer from 1 to 500, further preferably represents an integer from 2 to 100, particularly preferably represents an integer from 3 to 50, and particularly preferably represents an integer from 5 to 10.

[0065] Examples of the polyamine represented by the above formula (1) where m is 0 include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane (putrescine), 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, and 1,8-diaminooctane.

[0066] Examples of the polyamine represented by the above formula (1) in which m is 1 or more include: spermidine, spermine; polyethyleneamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexethyleneheptamine, heptaethyleneoctamine, octaethylenenonamine, and nonaethylenedecaamine; and polypropylenepolyamines such as dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine, pentapropylenehexamine, hexethyleneheptamine, heptapropyleneoctamine, octapropylenenonamine, and nonapropylenedecaamine.

[0067] As the polyamine represented by the above formula (1), commercially available products can be used. Table 1 shows examples of commercially available products.

[0068] ◎

Table 1

[0069] (Table 1)

[0070] Ingredient Name Product Name Molecular weight Manufacturer Pentamethylenediamine Pentamethylenediamine 102.18 Tokyo Chemical Industry Co., Ltd. Hexamethylenediamine Hexamethylenediamine 116.21 Tokyo Chemical Industry Co., Ltd. Putrescine Putrescine 88.15 MP Biomedicals, Inc Spermidine Spermidine, for molecular biology 145.25 Fujifilm Wako Pure Chemical Industries, Ltd. 1,3-Propylenediamine 1,3-Propylenediamine, light-grade 74.12 Fujifilm Wako Pure Chemical Industries, Ltd.

[0071] Examples of the polyamine include polymers having a structural unit derived from a cyclic amine represented by the following formula (2) (hereinafter sometimes referred to as "polymer A"). The polymer A can be obtained by ring-opening polymerization of the cyclic amine represented by the following formula (2).

[0072] ◎

Chemistry 2

[0073]

[0074] (Where R 3 , R 4 , R 5 , R 6 Each independently represents a hydrogen atom or a methyl group. )

[0075] Examples of the cyclic amine represented by the formula (2) include aziridine (ethyleneimine), 2-methylaziridine, 2,2-dimethylaziridine, 2,3-dimethylaziridine, etc. Examples of the homopolymer in the polymer A include polyethyleneimine, poly(2-methylaziridine), poly(2,2-dimethylaziridine), poly(2,3-dimethylaziridine), etc.

[0076] A commercially available product can be used as the polymer A. Table 2 shows examples of the commercially available product.

[0077] ◎

Table 2

[0078] (Table 2)

[0079] Ingredient Name Product Name Molecular weight Manufacturer Polyethyleneimine Polyethyleneimine (about 30% aqueous solution) 70,000 (weight average molecular weight) Tokyo Chemical Industry Co., Ltd.

[0080] Examples of the polyamine include polymers having a structural unit derived from an unsaturated amine represented by the following formula (3) (hereinafter sometimes referred to as "polymer B"). The polymer B can be obtained by polymerizing an unsaturated group of the unsaturated amine represented by the following formula (3).

[0081] ◎

Chemistry 3

[0082]

[0083] (where n represents an integer of 0 to 2, p represents an integer of 1 to 3, R 7 , R 8 , R 9 Each independently represents a hydrogen atom or a methyl group. )

[0084] Examples of the unsaturated amine represented by the formula (3) include vinylamine, divinylamine, trivinylamine, allylamine, diallylamine, triallylamine, methylallylamine, dimethylallylamine, trimethylallylamine, crotylamine, dicrotylamine, triprotylamine, 3-methyl-2-butenylamine, and 3-butenylamine.

[0085] Examples of the homopolymer in the polymer B include polyvinylamine, polydivinylamine, polyallylamine, polydiallylamine, polytriallylamine, polymethallylamine, polycrotylamine, and poly(3-butenylamine).

[0086] In addition, the polymer A and the polymer B may be copolymers in addition to the homopolymers. The copolymers may be arranged in any of statistical, random, alternating, and periodic copolymers, and the polymer chains may be connected in any of block copolymers and graft copolymers.

[0087] When the above-mentioned polymer A is a copolymer, it can be a copolymer of two or more cyclic amines shown in the above-mentioned formula (2). When the above-mentioned polymer B is a copolymer, it can be a copolymer of two or more unsaturated amines shown in the above-mentioned formula (3), or it can be a copolymer of one or more unsaturated amines shown in the above-mentioned formula (3) and other monomers that can copolymerize with the unsaturated amine shown in the above-mentioned formula (3).

[0088] Examples of other monomers copolymerizable with the unsaturated amine represented by the above formula (3) include sulfur dioxide, (meth)acrylamide, (meth)acrylate, (meth)acrylic acid ester, (meth)acrylic acid, and maleic acid.

[0089] When the polymer B is a copolymer, the proportion of the structural units derived from the unsaturated amine represented by the above formula (3) (including structural units in which a substituent is introduced into the amino group and structural units that form a salt) relative to the whole copolymer is, for example, 20% by mass or more, preferably 40% by mass or more, more preferably 60% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0090] Furthermore, when the polymer B is a copolymer, the proportion of structural units in which no substituent is introduced into the amino group among the structural units derived from the unsaturated amine represented by the above formula (3) relative to the entire copolymer is, for example, 20% by mass or more, preferably 40% by mass or more, more preferably 60% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0091] Representative examples of the polymer B having a structural unit derived from the unsaturated amine represented by the above formula (3) include polyvinylamine, polydivinylamine, polyallylamine, polydiallylamine, polytriallylamine, polymethylallylamine, polycrotylamine, poly(3-butenylamine), diallylamine polymers, poly(N,N-dimethylallylamine), poly(N-acetyllylamine) and the like homopolymers, allylamine-diallylamine copolymers, allylamine-dimethylallylamine copolymers, partially methoxycarbonylated allylamine copolymers, partially ureidated allylamine copolymers, and the like. Amine polymers, diallylamine-sulfur dioxide copolymers, methyldiallylamine-sulfur dioxide copolymers, diallylamine-acrylamide copolymers, allylamine-maleic acid copolymers, diallylamine-maleic acid copolymers, methyldiallylamine-maleic acid copolymers, partially formylated allylamine polymers, partially acetylated allylamine polymers, partially propionylated allylamine polymers, allylamine-N,N-dimethylallylamine copolymers, partially formylated diallylamine polymers, partially acetylated diallylamine polymers, partially propionylated diallylamine polymers and the like copolymers.

[0092] Furthermore, the amino group in the molecule of any of the polyamine represented by the above formula (1), the above polymer A, and the above polymer B may or may not have a substituent.

[0093] Examples of the substituent include: alkyl groups having 1 to 4 carbon atoms, such as methyl and ethyl groups; acyl groups having 1 to 4 carbon atoms, such as formyl, acetyl, and propionyl groups; alkoxycarbonyl groups having 1 to 4 carbon atoms in the alkoxy moiety, such as methoxycarbonyl and ethoxycarbonyl groups; and carbamoyl groups. These substituents may be introduced at the monomer stage or after polymerization. The substituents may be one or more.

[0094] The polyamine is preferably at least one compound selected from the polyamine represented by the above formula (1), the polymer A, or the polymer B. Among them, the polyamine is more preferably any one of the polymer A and / or the polymer B, and most preferably the polymer B, from the viewpoint of being more economical and easier to obtain.

[0095] A commercially available product can be used as the polymer B. Table 3 shows examples of the commercially available product.

[0096] ◎

Table 3

[0097] (Table 3)

[0098] Ingredient Name Product Name Molecular weight Manufacturer Polyallylamine PAA-01 (15% aqueous solution) 1600(weight average molecular weight) Nittobo Medical Co., Ltd. Polyallylamine PAA-15C (15% aqueous solution) 15,000 (weight average molecular weight) Nittobo Medical Co., Ltd. Diallylamine polymer PAS-21 (15% aqueous solution) 5,000 (weight average molecular weight) Nittobo Medical Co., Ltd.

[0099] The salt of the polyamine may be any of a salt with an acid and a quaternary ammonium salt. Examples of the acid include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and boric acid; monobasic aliphatic carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, octanoic acid, decanoic acid, and dodecanoic acid; dibasic aliphatic carboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid; hydroxycarboxylic acids such as glycolic acid, lactic acid, malic acid, and tartaric acid; and organic acids such as sulfonic acids such as methanesulfonic acid and p-toluenesulfonic acid.

[0100] The aqueous solution may also contain various additives as other components without damaging the effects of the present invention. As the other components, for example, one or more organic solvents, thickening stabilizers, tackifiers, preservatives, surfactants, quality stabilizers, etc. may be used.

[0101] It should be noted that the aqueous solution preferably does not substantially contain lithium ions, and more preferably does not substantially contain metal ions. By making the aqueous solution substantially free of metal ions, wastewater treatment after use becomes easy. It should be noted that, in the present invention, substantially free of metal ions means: raw materials containing metal elements other than the impregnated electrode material are not actively added, for example, the metal ion concentration in the aqueous solution is 1.0 mol / L or less.

[0102] From the viewpoint of maximizing the functions of the polyamine and / or its salt, the content of other components in the aqueous solution other than water, polyamine and polyamine salt is preferably less than 5% by mass, more preferably less than 3% by mass, further preferably less than 1% by mass, and particularly preferably not added, relative to 100% by mass of the aqueous solution. When the content of other components is less than 5% by mass, there is no interference by other components in the aqueous solution, so the effect of the polyamine and / or its salt is more effectively exerted.

[0103] The above-mentioned aqueous solution contains polyamine and / or its salt as functional components, and the total content of water, polyamine and polyamine salt is, relative to 100 mass % of the above-mentioned aqueous solution, for example, 95 mass % or more, preferably 98 mass % or more, 99 mass % or more, more preferably 99.5 mass % or more, further preferably 99.95 mass % or more, particularly preferably 99.98 mass % or more, and most preferably 100 mass %.

[0104] The pH of the aqueous solution immediately after preparation is preferably 8.6 to 14, more preferably 9 to 13, and even more preferably 9.5 to 12. When the pH is 8.6 or higher, carbon dioxide can be fully absorbed, and when the pH is 14 or lower, the aqueous solution is sufficiently safe and wastewater treatment becomes easy.

[0105] The aqueous solution is preferably capable of dissolving carbon dioxide in the atmosphere to a saturated concentration. By having the above configuration, carbon dioxide in the atmosphere can be efficiently fixed.

[0106] In order to allow the aqueous solution to dissolve carbon dioxide in the atmosphere to a saturated concentration, it is preferably left to stand at room temperature and normal pressure for 100 hours or more.

[0107] The pH of the aqueous solution after standing in the atmosphere (preferably after standing in the atmosphere for more than 100 hours) is preferably 7.5 to 10, more preferably 7.7 to 9.5, and even more preferably 8.1 to 9.0. By making the pH of the aqueous solution containing the polymer compound after standing within the above range, it can be confirmed that carbon dioxide is fully absorbed.

[0108] (Electrode Material)

[0109] The carbon dioxide fixation device includes positive and negative electrode materials. The positive and negative electrode materials may be electrode materials each containing only one raw material or may be electrode materials containing two or more raw materials.

[0110] As the negative electrode material, a known or commonly used negative electrode material can be used. Among them, as the negative electrode material, preferably: a material whose standard Gibbs energy of formation of carbonate is lower than the standard Gibbs energy of formation of hydroxide. If the standard Gibbs energy of formation of carbonate of the negative electrode material is lower than the standard Gibbs energy of formation of hydroxide, carbonate is easily generated after power is applied (after discharge) in the carbon dioxide fixation device.

[0111] In addition, the solubility product in water has an inherent value for a single salt, and when the product of the molar concentrations of the ion species constituting the salt exceeds the solubility product, the salt precipitates in the form of crystals. Therefore, when metal ions and atmospheric carbon dioxide are continuously supplied to the above-mentioned aqueous solution, carbonates can be continuously precipitated therefrom. When the above-mentioned carbon dioxide fixation device is powered on, metal ions are continuously dissolved into the aqueous solution through the oxidation reaction of the negative electrode, and react with carbon dioxide to form carbonates, so it becomes easy to produce carbonates.

[0112] Specifically, the negative electrode material preferably contains a metal element other than an alkali metal, more preferably contains one or more metal elements selected from zinc, iron, copper and magnesium, further preferably contains one or more metal elements selected from zinc, iron and magnesium, and particularly preferably contains zinc. By making the negative electrode material not contain an alkali metal, it is easy to ensure safety. In addition, by containing one or more metal elements selected from zinc, iron and magnesium, it is easy to be fixed in the form of carbonate after power is applied.

[0113] The content of the metal other than the alkali metal in the negative electrode material is preferably 90% by mass or more, more preferably 95% by mass or more, and further preferably 100% by mass, relative to 100% by mass of the negative electrode material. By satisfying the above range, carbon dioxide in the aqueous solution (electrolyte) can be easily fixed in the form of carbonate when electricity is supplied.

[0114] The standard Gibbs energy of formation of the hydroxide generated from the negative electrode material is preferably -200 kJ / mol or less, more preferably -300 kJ / mol or less, and further preferably -400 kJ / mol or less. In addition, the lower limit is not particularly limited, but is preferably -1000 kJ / mol or more.

[0115] The standard Gibbs energy of formation of the carbonate generated by the negative electrode material is preferably -500 kJ / mol or less, more preferably -600 kJ / mol or less, and further preferably -700 kJ / mol or less. By making the standard Gibbs energy of formation of the carbonate below -500 kJ / mol, carbonate is easily generated. In addition, as a lower limit, there is no particular restriction, but it is preferably above -3000 kJ / mol.

[0116] In addition, the standard Gibbs energy of formation of the carbonate is preferably 100 kJ / mol or more smaller than the standard Gibbs energy of formation of the hydroxide, more preferably 150 kJ / mol or more smaller, and further preferably 200 kJ / mol or more smaller. By satisfying the above range, carbonate can be stably generated when the carbon dioxide fixation device is powered on.

[0117] The standard Gibbs energy of formation of a substance generated from the negative electrode material is preferably -300 kJ / mol or less, more preferably -400 kJ / mol or less, and further preferably -500 kJ / mol or less. When the standard Gibbs energy of formation of a substance generated from the negative electrode material is within the above range, it is easy to use as a negative electrode.

[0118] The shape of the negative electrode material is not particularly limited, and a plate-like, rod-like, pellet-like, or other shape may be used in accordance with the shape of the carbon dioxide fixation device.

[0119] As the positive electrode material, a known or commonly used positive electrode material can be used. In particular, the positive electrode material is preferably formed of a material that achieves a relatively higher standard generation Gibbs energy than the negative electrode material. It should be noted that, as a whole, if the positive electrode material achieves a higher standard generation Gibbs energy than the negative electrode material, it may also include a material with a lower standard generation Gibbs energy than the negative electrode material, but it is preferably not included. By having the above-mentioned structure, when the carbon dioxide fixation device is powered on, it is easy to extract energy.

[0120] As the positive electrode material, for example, manganese dioxide, carbon, etc. can be used. When carbon is used as the positive electrode material, an air electrode using oxygen in air as the positive electrode is formed.

[0121] The standard generation Gibbs energy of the substance generated by the above-mentioned positive electrode material is preferably -500kJ / mol or more, more preferably -400kJ / mol or more, and further preferably -300kJ / mol or more. By satisfying the above range, it is easy to use as a positive electrode. It should be noted that, when using carbon as a positive electrode material, the standard generation Gibbs energy of the substance generated by oxygen in the air preferably satisfies the above range.

[0122] In addition, the difference between the change amount of the standard generation Gibbs energy of the above-mentioned negative electrode material and the positive electrode material is preferably 200kJ / mol or more, more preferably 250kJ / mol or more, and further preferably 300kJ / mol or more. By making the difference in the change amount of the standard generation Gibbs energy be 200kJ / mol or more, as a battery, it is easy to make the electromotive force sufficient. In addition, although there is no special restriction as an upper limit, it is preferably less than 2000kJ / mol.

[0123] The shape of the positive electrode material is not particularly limited, and the positive electrode material may be in the form of a plate, a rod, or a pellet.

[0124] There is no particular limitation on the combination of the negative electrode material and the positive electrode material, but preferably the combination is: using zinc or magnesium as the negative electrode material and manganese dioxide as the positive electrode material; or using zinc or magnesium as the negative electrode material and carbon as the positive electrode material.

[0125] In the carbon dioxide fixation device, the liquid surface of the aqueous solution is preferably in contact with the atmosphere. The aqueous solution is highly safe and can be used even in a state of contact with the atmosphere. When the water-soluble polymer compound is non-volatile, it does not volatilize even in contact with the atmosphere and can efficiently absorb carbon dioxide in the atmosphere.

[0126] In order to stabilize the initial voltage, the carbon dioxide fixation device is preferably left to stand before power is supplied. Then, the carbon dioxide fixation device is connected to an external circuit and powered on, thereby extracting energy while allowing the carbon dioxide in the aqueous solution to react, thereby fixing and precipitating the carbon dioxide in the form of carbonate.

[0127] The carbonate described above depends on the material of the negative electrode material used, but is preferably an alkaline carbonate, and specific examples thereof include zinc carbonate, iron carbonate, magnesium carbonate, magnesium carbonate trihydrate, magnesium carbonate pentahydrate, copper carbonate, and alkaline carbonates thereof, and zinc carbonate and alkaline zinc carbonate are particularly preferred.

[0128] The pH of the aqueous solution after energization is preferably 5.8 or more and less than 8.6, more preferably 6.0 or more and 8.4 or less, and further preferably 6.2 or more and 8.2 or less. By making the pH of the aqueous solution after energization satisfy the above range, drainage to rivers or public sewers can be made easy and safe.

[0129] Since the carbon dioxide fixation device has the above-mentioned structure, it is possible to extract energy while fixing carbon dioxide in the atmosphere. As the above-mentioned energy, electrical energy is preferred. In addition, as its charge, it is preferably 108C or more, more preferably 150C or more, and further preferably 200C or more. By being able to extract 108C or more of the above-mentioned electrical energy, it is suitable for use as a battery.

[0130] Furthermore, the carbon dioxide fixation device after energization can repeatedly fix and precipitate carbon dioxide and extract energy by absorbing carbon dioxide in the atmosphere again into the aqueous solution.

[0131] Furthermore, the carbonate is precipitated in the aqueous solution and can be easily recovered from the carbon dioxide fixation device. The aqueous solution after the carbonate is recovered contains only low concentrations of polyamine and components derived from the electrode, so it is highly safe and easy to treat as wastewater.

[0132] [Battery]

[0133] As one embodiment of the present invention, a battery including the above-mentioned carbon dioxide fixation device can be cited. The above-mentioned battery uses the above-mentioned aqueous solution as an electrolyte, and can be used as a battery that can recover carbon dioxide in the atmosphere while fixing it. Furthermore, the above-mentioned battery can be used repeatedly by reabsorbing carbon dioxide in the atmosphere into the above-mentioned electrolyte, so that it can function as a negative emission system that fixes carbon dioxide in the atmosphere, and further, even without input of energy from the outside, it can also extract electrical energy in the form of a battery.

[0134] Example

[0135] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0136] Example 1

[0137] 75 ml of a water-soluble polymer aqueous solution containing polyallylamine with a molecular weight of 1600 and a concentration of 100 mass ppm was prepared in a glass beaker, and the pH thereof was measured to be 10.18. The aqueous solution was allowed to stand for 150 hours at 18 to 22° C. in contact with the atmosphere, and the pH was measured again to be 8.22, presumably indicating that carbon dioxide in the atmosphere was absorbed into the water-soluble polymer aqueous solution.

[0138] Reference Example 1

[0139] A 10-fold concentrated solution (concentration 1000 mass ppm) of polyallylamine water-soluble polymer aqueous solution was prepared instead of the water-soluble polymer aqueous solution of Example 1, and its pH was measured to be 11.19. The same test was performed on the concentrated solution of Reference Example 1, and the pH was confirmed to be reduced to 8.60.

[0140] The pH of both Example 1 and Reference Example 1 decreased after standing, confirming the absorption of carbon dioxide in the atmosphere. In addition, when Example 1 was compared with Reference Example 1, since the error between Example 1 and the pH estimated from the carbon dioxide concentration in the atmosphere was small, the aqueous solution of Example 1 was used in subsequent tests.

[0141] (Preparation of Carbon Dioxide Fixation Device)

[0142] As the positive electrode material, a carbon rod, terminal, and electrode plate holder of a carbon rod set for electrolysis (trade name "B10-2064", manufactured by Narika Co., Ltd.) were used and placed in a separation cup (trade name "Daniel Battery DT-B", manufactured by Narika Co., Ltd.). Next, a mixture of granular manganese (IV) oxide (manufactured by Hayashi Junyaku Kogyo Co., Ltd.) crushed to 3 mm and powdered graphite (trade name "FK-300", manufactured by Monami Co., Ltd.) was spread over the separation cup to make a positive electrode.

[0143] The positive electrode was placed in a 100 ml beaker (trade name "PB-100", manufactured by Niigata Seiki Co., Ltd.), and a zinc plate was placed as a negative electrode on the negative electrode side separated from the positive electrode side by the separation cup. Then, about 50 ml of the aqueous solution of Example 1 was added to prepare the carbon dioxide fixation device of Example 1.

[0144] like Figure 1 As shown, two sets of carbon dioxide fixation devices of Example 1 were prepared, and the voltage was measured at the stage where the liquid surface of the above-mentioned aqueous solution was connected in series in a manner in contact with the air. As a result, 2.5V was output at 1.25V×2. After 21 hours, the voltage rose to 2.8V, and it was also 2.8V after 24 hours. Therefore, it was judged that the initial voltage before discharge was reached at this time, and it was provided for the discharge test described later. It should be noted that, according to the degree of penetration of the electrolyte into the positive electrode side, about 10ml of the above-mentioned aqueous solution was added, and the liquid surface was flush with the position of 100ml on the scale of the beaker.

[0145] Regarding the evaluation method of the carbon dioxide fixation device, a red light emitting diode (hereinafter referred to as LED) that can be visually observed to be powered was used as a load, and the circuit was a series circuit of the LED and an LED current limiting resistor (hereinafter referred to as R) of 326.9Ω (measured value).

[0146] In addition, regarding the acquired data, at two points of the carbon dioxide fixation device terminal voltage and the voltage across R, the current was obtained by dividing the voltage across R by the resistance value of 326.9Ω (measured value) as the current value.

[0147] (Discharge test)

[0148] The aqueous solution was subjected to multiple discharge tests under the following conditions, and the pH, voltage and current of the aqueous solution were measured simultaneously, and the average current and charge were calculated. The results are recorded in Figure 2 , 3 and Tables 4 and 5.

[0149] 1. During the first discharge, the power supply is maintained until the LED light emission is no longer confirmed.

[0150] 2. After the discharge is completed, let it stand until the voltage exceeds 2.77V, which is 99% of the pre-discharge voltage of 2.8V, and the recovery is considered complete, and the second discharge is started.

[0151] 3. During the second discharge, the power supply is maintained until the light emission of the LED can no longer be confirmed.

[0152] 4. After the second discharge, let it stand and check the voltage recovery characteristics. When it exceeds 99% of 2.77V, that is, 2.74V, it is considered to be recovery complete. Replace the zinc plate with a new one and repeat the discharge / recovery.

[0153]

Table 4

[0154] Table 4

[0155] Time [h] Current [μA] Voltage [V] ① Before the first discharge 0 - 2.80 ② The first discharge starts 0 574.4 1.85 ③ The first discharge is completed 1248 46.50 1.52 ④ The first recovery is completed 1824 - 2.77 ⑤ The second discharge starts 1824 557.4 1.80 ⑥ The second discharge is completed 2064 67.91 1.54 ⑦ The second recovery is over 2760 - 2.86 ⑧ The third discharge starts 2760 691.6 1.91 ⑨ The third discharge is completed 3000 43.44 1.52 ⑩ The third recovery is over 3504 - 2.70

[0156]

Table 5

[0157] Table 5

[0158] Charge [C] Average current [μA] The first discharge test 522.8 116.6 Second discharge test 90.2 104.3 The third discharge test 76.3 88.3

[0159] The carbon dioxide fixation device of Example 1 has the following implications: the carbon dioxide fixation device is based on 30 mAh (= 108 C) and can continuously discharge beyond this base, so that energy can be taken out and can be used as a battery. The following implications are: by setting a recovery period for reabsorbing carbon dioxide into the aqueous solution, it can be regenerated as a battery and can be used repeatedly.

[0160] In addition, the zinc plate of the negative electrode after the above discharge test was subjected to powder X-ray diffraction, and the result showed that no zinc oxide was confirmed, but basic zinc carbonate Zn5(OH)6(CO3)2 was confirmed. That is, it was confirmed that the carbon dioxide in the atmosphere was absorbed into the above aqueous solution, functioned as a component of the battery electrolyte, and was fixed in the form of carbonate.

[0161] Example 2

[0162] The carbon dioxide fixation device of Example 2 was prepared in the same manner as in Example 1, except that activated carbon (trade name "Granular Activated Carbon for Gas Phase 4GG", manufactured by ASONE Co., Ltd.) was used instead of granular manganese (IV) oxide (manufactured by Hayashi Jun Chemical Industries, Ltd.) crushed to 3 mm and powdered graphite (trade name "FK-300", manufactured by Monami Co., Ltd.) as the positive electrode material.

[0163] Two sets of carbon dioxide fixation devices of Example 2 were prepared, and the voltage was measured at the stage where the liquid surface of the above-mentioned aqueous solution was connected in series in a manner that the liquid surface was in contact with the air. As a result, the output was 1.652V. Since the electrolyte slowly penetrates to the positive electrode (activated carbon) side while passing through the separator, electrolytic water is appropriately supplemented to maintain the position where the scale of the beaker is 100ml, and the voltage characteristics are measured at the same time. It takes time for the voltage to rise in the activated carbon positive electrode of Example 2, and white corrosion products believed to be caused by self-discharge are accumulated on the zinc plate of the negative electrode. It is judged that it finally reaches about 1.99V at the moment of 168 hours (7 days). Although a further upward trend is also observed, it is set as the initial voltage before discharge for the discharge test described later.

[0164] (Discharge test)

[0165] The discharge test was conducted by maintaining the power supply until the light emission of the LED could no longer be confirmed, and the pH, voltage and current of the aqueous solution of Example 2 were measured. Figure 4 , 5 Shown in.

[0166] The carbon dioxide fixation device of Example 2 is as follows Figure 4 As shown in the figure, the discharge lasted for 1824 hours (76 days), and the average voltage during the discharge was 1.614V (maximum value 1.630V, minimum value 1.578V). Figure 5 As shown, the average current is 157.1 μA, the pH of the electrolyte at the end of discharge is 7.27, and the charge reaches 1031.5C.

[0167] In addition, the zinc plate of the carbon dioxide fixation device of Example 2 after the above-mentioned discharge test was subjected to powder X-ray diffraction, and as a result, basic zinc carbonate Zn5(OH)6(CO3)2 was confirmed. Therefore, the carbon dioxide fixation device of Example 2 can also extract energy in the form of a battery. In addition, it was confirmed that the carbon dioxide in the atmosphere was absorbed into the above-mentioned aqueous solution and fixed while functioning as a component of the electrolyte of the battery.

[0168] Comparative Example 1

[0169] 75 ml of a 0.1 mmol / L potassium hydroxide aqueous solution was prepared in a glass beaker, and its pH was measured to be 10.55. The aqueous solution was left to stand at 18 to 22°C in contact with the atmosphere for 120 hours and the pH was measured again to be 7.73, presumably indicating that carbon dioxide in the atmosphere was absorbed into the potassium hydroxide aqueous solution.

[0170] A carbon dioxide fixation apparatus of Comparative Example 1 was prepared in the same manner as in Example 2 except that the above potassium hydroxide aqueous solution was used instead of the aqueous solution of Example 2.

[0171] Two sets of carbon dioxide fixation devices of Comparative Example 1 were prepared, and the voltage was measured at the stage where the liquid surface of the aqueous solution was connected in series in a manner that it was in contact with the air. The result was 1.690 V. Since the electrolyte slowly permeates to the positive electrode (activated carbon) side while passing through the separator, the electrolytic water was appropriately supplemented to maintain the position where the scale of the beaker was 100 ml, and the voltage characteristics were measured at the same time. It was determined that 1.986 V was finally reached at the moment of 168 hours (7 days), which was set as the initial voltage before discharge for the discharge test described later.

[0172] (Discharge test)

[0173] The discharge test was conducted by maintaining the power supply until the light emission of the LED could no longer be confirmed, and the pH, voltage, and current of the aqueous solution of Comparative Example 1 were measured. Figure 6 , 7 Shown in.

[0174] The carbon dioxide fixation device of Comparative Example 1 is as follows Figure 6 As shown in the figure, the discharge lasted for 1800 hours (75 days), and the average voltage during discharge was 1.594V (maximum value 1.660V, minimum value 1.560V). Figure 7 As shown, the average current is 142.4μA, the pH of the electrolyte at the end of discharge is 7.08, and the charge reaches 900C.

[0175] In addition, the zinc plate of the carbon dioxide fixation device of Comparative Example 1 after the above-mentioned discharge test was subjected to powder X-ray diffraction, and the result confirmed basic zinc carbonate Zn5(OH)6(CO3)2. Therefore, the carbon dioxide fixation device of Comparative Example 1 can also extract energy in the form of a battery. In addition, it was confirmed that the carbon dioxide in the atmosphere was absorbed into the above-mentioned aqueous solution and fixed while functioning as a component of the electrolyte of the battery.

[0176] When the carbon dioxide fixation device of Example 2 is compared with the carbon dioxide fixation device of Comparative Example 1, the results are as follows: the average voltage, average current and charge amount of the carbon dioxide fixation device of the embodiment are better, and the carbon dioxide in the atmosphere can be fixed more efficiently, and can be used as a battery. In addition, the carbon dioxide fixation device of Example 2 is a safer device than Comparative Example 1 using potassium hydroxide aqueous solution.

[0177] Modifications of the present invention will be described below.

[0178] [Supplementary Note 1] A carbon dioxide fixation device comprising an aqueous solution containing a water-soluble polymer compound, a positive electrode material, and a negative electrode material, wherein carbonate from carbon dioxide can be generated by passing electricity through the electrode materials.

[0179] [Appendix 2] The carbon dioxide fixation device according to Appendix 1, wherein the weight average molecular weight of the water-soluble polymer compound is 500 or more and 150,000 or less.

[0180] [Appendix 3] The carbon dioxide fixation device according to Appendix 1 or 2, wherein the water-soluble polymer compound has two or more amino groups in the molecule.

[0181] [Appendix 4] The carbon dioxide fixation device according to any one of Appendices 1 to 3, wherein the water-soluble polymer compound is a non-volatile polyamine.

[0182] [Appendix 5] The carbon dioxide fixation device according to any one of Appendices 1 to 4, wherein the water-soluble polymer compound is a non-volatile polyamine having two or more amino groups in the molecule and a weight average molecular weight of 500 to 50,000.

[0183] [Appendix 6] The carbon dioxide fixation device according to any one of Appendices 1 to 5, wherein the concentration of the water-soluble polymer compound in the aqueous solution is 1 mass ppm or more and less than 1000 mass ppm.

[0184] [Appendix 7] The carbon dioxide fixation device according to Appendix 4 or 5, comprising polyallylamine as the polyamine.

[0185] [Appendix 8] The carbon dioxide fixation apparatus according to any one of Appendices 1 to 7, wherein the pH of the aqueous solution immediately after preparation is 8.6 or more and 14 or less.

[0186] [Appendix 9] The carbon dioxide fixation device according to any one of Appendices 1 to 8, wherein the pH of the aqueous solution after being left to stand in the atmosphere is 7.5 or more and 10 or less.

[0187] [Appendix 10] The carbon dioxide fixation device according to any one of Appendices 1 to 9, wherein the aqueous solution contains substantially no metal ions before power is supplied.

[0188] [Appendix 11] The carbon dioxide fixation apparatus according to any one of Appendices 1 to 10, wherein the liquid surface of the aqueous solution is in contact with the atmosphere.

[0189] [Appendix 12] The carbon dioxide fixation device according to any one of Appendices 1 to 11, which is capable of dissolving carbon dioxide in the atmosphere in the aqueous solution to a saturated concentration before power is supplied.

[0190] [Appendix 13] The carbon dioxide fixation device according to any one of Appendices 1 to 12, wherein the negative electrode material contains a metal element other than an alkali metal.

[0191] [Appendix 14] The carbon dioxide fixation device according to any one of Appendices 1 to 13, wherein the negative electrode material contains one or more metal elements selected from zinc, iron and magnesium.

[0192] [Appendix 15] The carbon dioxide fixation device according to any one of Appendices 1 to 14, wherein the positive electrode material is formed of a material having a higher standard Gibbs energy of formation than that of the negative electrode material.

[0193] [Appendix 16] The carbon dioxide fixation device according to any one of Appendices 1 to 15, wherein the positive electrode material contains manganese dioxide and / or carbon.

[0194] [Note 17] The carbon dioxide fixation device according to any one of Notes 1 to 16, wherein the difference in the amount of change in the standard Gibbs energy of formation between the negative electrode material and the positive electrode material is 200 kJ / mol or more.

[0195] [Supplementary Note 18] The carbon dioxide fixation device according to any one of Supplementary Notes 1 to 17, which is capable of extracting electrical energy.

[0196] [Appendix 19] The carbon dioxide fixation device according to any one of Appendices 1 to 18, which is capable of repeatedly fixing and precipitating carbon dioxide while extracting energy.

[0197] [Supplementary Note 20] The carbon dioxide fixation device according to any one of Supplementary Notes 1 to 19, wherein the pH of the aqueous solution is 5.8 or more and less than 8.6 when the power is turned on.

[0198] [Appendix 21] A battery comprising the carbon dioxide fixation device according to any one of Appendices 1 to 20.

Claims

1. A carbon dioxide fixation device comprising an aqueous solution containing a water-soluble polymer compound, a positive electrode material, and a negative electrode material, In the carbon dioxide fixation device, carbonate can be generated from carbon dioxide by passing electricity through the positive electrode material and the negative electrode material.

2. The carbon dioxide fixation device according to claim 1, wherein: The water-soluble polymer compound has a weight average molecular weight of 500 or more and 150,000 or less.

3. The carbon dioxide fixation device according to claim 1 or 2, wherein: The water-soluble polymer compound has two or more amino groups inside the molecule.

4. The carbon dioxide fixation device according to claim 1 or 2, wherein: The water-soluble high molecular compound is a non-volatile polyamine.

5. The carbon dioxide fixation device according to claim 1 or 2, wherein: The water-soluble polymer compound is a non-volatile polyamine having two or more amino groups in the molecule and a weight average molecular weight of 500 to 50,000.

6. The carbon dioxide fixation device according to claim 1 or 2, wherein: The concentration of the water-soluble polymer compound in the aqueous solution is 1 mass ppm or more and less than 1000 mass ppm. 7 . The carbon dioxide fixation device according to claim 4 , comprising polyallylamine as the polyamine. 8 . The carbon dioxide fixation device according to claim 5 , comprising polyallylamine as the polyamine.

9. The carbon dioxide fixation device according to claim 1 or 2, wherein: The pH of the aqueous solution immediately after preparation is 8.6 or more and 14 or less.

10. The carbon dioxide fixation device according to claim 1 or 2, wherein: The pH of the aqueous solution after being left to stand in the air is 7.5 or more and 10 or less.

11. The carbon dioxide fixation device according to claim 1 or 2, wherein: In a state before power is supplied, the aqueous solution contains substantially no metal ions.

12. The carbon dioxide fixation device according to claim 1 or 2, wherein: The liquid surface of the aqueous solution is in contact with the atmosphere. 13 . The carbon dioxide fixation device according to claim 1 or 2 , which can dissolve carbon dioxide in the atmosphere in the aqueous solution to a saturated concentration before power is supplied.

14. The carbon dioxide fixation device according to claim 1 or 2, wherein: The negative electrode material contains a metal element other than an alkali metal.

15. The carbon dioxide fixation device according to claim 1 or 2, wherein: The negative electrode material includes one or more metal elements selected from zinc, iron and magnesium.

16. The carbon dioxide fixation device according to claim 1 or 2, wherein: The positive electrode material is formed of a material having a higher standard generation Gibbs energy than that of the negative electrode material.

17. The carbon dioxide fixation device according to claim 1 or 2, wherein: The positive electrode material comprises manganese dioxide and / or carbon.

18. The carbon dioxide fixation device according to claim 1 or 2, wherein: The difference in change in standard Gibbs energy of formation between the negative electrode material and the positive electrode material is 200 kJ / mol or more.

19. The carbon dioxide fixation device according to claim 1 or 2, which is capable of extracting electrical energy.

20. The carbon dioxide fixation device according to claim 1 or 2, which can repeatedly fix and precipitate carbon dioxide while extracting energy.

21. The carbon dioxide fixation device according to claim 1 or 2, wherein: When the power is supplied, the pH of the aqueous solution is 5.8 or more and less than 8.

6.

22. A battery comprising the carbon dioxide fixation device according to claim 1 or 2.

Images