Carbon dioxide concentration device

Abstract

The present invention pertains to a carbon dioxide concentration device provided with a first electrode belonging to a cathode, a second electrode belonging to an anode disposed so as to be spaced apart from the first electrode, and at least one electrolyte solution filled between the first electrode and the second electrode and present in contact with the first electrode and the second electrode, at least one of the electrolyte solutions contains a compound represented by formula (1) or a salt thereof, and water. (In formula (1), R1 to R10 each independently represent a hydrogen atom, an alkyl group, a hydroxyl group or a salt thereof, an alkoxy group, a nitro group, an amino group, a mercapto group, a cyano group, a halogen group, an aryl group, a sulfonic acid group or a salt thereof, a carboxyl group or a salt thereof, a carbonyl group, a sulfonyl group, or a heteroaryl group. )

Description

TECHNICAL FIELD

[0001] The present application relates to a carbon dioxide concentration device. BACKGROUND

[0002] In recent years, more active attempts have been made to recover carbon dioxide, which is a cause of global warming, from the atmosphere and factory exhaust and store it in the ground or resource it. As a means for recovering carbon dioxide, a method using an electrochemical device is known. For example, a device is disclosed in Patent Documents 1 and 2, which dissolves or releases carbon dioxide from an electrolyte using an electrochemical reaction of oxygen generation / oxygen reduction, whereby carbon dioxide can be enriched.

[0003] On the other hand, in order to further improve the recovery efficiency of carbon dioxide, it is required to develop a novel carbon dioxide concentration device that can selectively extract and concentrate carbon dioxide using an electrochemical reaction.

[0004] [Related Art Documents]

[0005] [Patent Documents]

[0006] Patent Document 1: International Publication No. WO2012 / 164912

[0007] Patent Document 2: International Publication No. WO2012 / 164913. SUMMARY

[0008] [Problems to be Solved by the Invention]

[0009] An object of the present application is to provide a novel carbon dioxide concentration device that exhibits the property of being able to selectively concentrate carbon dioxide using an electrochemical reaction.

[0010] [Means of Solving the Problems]

[0011] As a result of intensive studies by the present inventors and others, it has been found that, in an electrochemical method, a compound having a fluoflavine skeleton representing a specific structure is used as a mediator, whereby a pH gradient is generated between electrodes by an oxidation-reduction reaction in an electrolyte. As a result, a novel carbon dioxide concentration device that exhibits the property of being able to selectively concentrate carbon dioxide using an electrochemical reaction can be provided, thereby completing the present application.

[0012] The carbon dioxide concentration device according to the present application includes a first electrode belonging to a cathode, a second electrode belonging to an anode disposed apart from the first electrode, and at least one electrolyte filled between the first electrode and the second electrode and present in contact with the first electrode and the second electrode,

[0013] At least one of the electrolytes contains a compound represented by the following formula (1) or a salt thereof, and water.

[0014]

[0015] (in formula (1), R 1 to R 10 each independently represent a hydrogen atom, an alkyl group, a hydroxyl group or a salt thereof, an alkoxy group, a nitro group, an amino group, a mercapto group, a cyano group, a halogen group, an aryl group, a sulfonic acid group or a salt thereof, a carboxyl group or a salt thereof, a carbonyl group, a sulfonyl group, or a heteroaryl group.)

[0016] In one embodiment of the present application, in the aforementioned formula (1), at least one of R 1 to R 8 is a sulfonic acid group or a salt thereof.

[0017] In one embodiment of the present application, in the aforementioned formula (1), at least two of R 1 to R 8 are sulfonic acid groups or salts thereof.

[0018] In one embodiment of the present application, in the aforementioned formula (1), at least one of R 1 to R 8 is a group selected from the group consisting of an alkyl group, an alkoxy group, a halogen group, and a carboxyl group or a salt thereof.

[0019] In one embodiment of the present application, a separator is further provided between the aforementioned first electrode and the aforementioned second electrode.

[0020] In one embodiment of the present application, a first electrolyte which is present between the aforementioned first electrode and the aforementioned separator and in contact with the aforementioned first electrode, and a second electrolyte which is present between the aforementioned second electrode and the aforementioned separator and in contact with the aforementioned second electrode, are provided, wherein the aforementioned first electrolyte contains the compound represented by the aforementioned formula (1) or a salt thereof, and water.

[0021] In one embodiment of the present application, the aforementioned first electrolyte and the aforementioned second electrolyte are mutually different electrolytes.

[0022] [Effects of the Invention]

[0023] An object of the present application is to provide a novel carbon dioxide concentration device which exhibits the property of selectively concentrating carbon dioxide using an electrochemical reaction. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A schematic view showing an example of the carbon dioxide concentration device of the present embodiment.

[0025] Figure 2 A cyclic voltammogram obtained by the redox resistance evaluation 1.

[0026] Figure 3A cyclic voltammogram obtained by the redox tolerance evaluation 2. DETAILED DESCRIPTION

[0027] The present application is described in detail below. In addition, "parts" and "%" described below are all on a mass basis unless otherwise specified, and are also the same in examples and the like. In addition, the description of "compound or salt thereof" is sometimes simply referred to as "compound" for convenience.

[0028] As Figure 1 indicated, the carbon dioxide concentration device 10 of the present embodiment is provided with a first electrode 1 belonging to a cathode, a second electrode 2 belonging to an anode disposed apart from the first electrode 1, and at least one kind of electrolyte 3 filled between the first electrode 1 and the second electrode 2 and existing in contact with the first electrode 1 and the second electrode 2. The at least one kind of electrolyte contains a tetraaza fused tetrabenzenoid compound, and more preferably contains a compound represented by the following formula (1) which functions as a mediator.

[0029]

[0030] [Compound represented by formula (1)]

[0031] In the above-mentioned compound represented by formula (1), R 1 to R 10 independently represent a hydrogen atom, an alkyl group, a hydroxyl group or a salt thereof, an alkoxy group, a nitro group, an amino group, a mercapto group, a cyano group, a halogen group, an aryl group, a sulfonic acid group or a salt thereof, a carboxyl group or a salt thereof, a carbonyl group, a sulfonyl group, or a heteroaryl group.

[0032] The above-mentioned alkyl group can be exemplified by a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group, and the like.

[0033] The above-mentioned alkoxy group can be exemplified by a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a t-butoxy group, and the like.

[0034] The above-mentioned amino group can be exemplified by an amino group (-NH2), a methylamino group, a dimethylamino group, an ethylamino group, a diethylamino group, and the like.

[0035] The above-mentioned halogen group can be exemplified by a fluorine group, a chlorine group, a bromine group, an iodine group, and the like.

[0036] The above-mentioned aryl group can be exemplified by a phenyl group, a naphthyl group, and the like.

[0037] The above-mentioned carbonyl group can be exemplified by an acetyl group, a trimethylacetyl group, a benzoyl group, and the like.

[0038] The above-mentioned sulfonyl group can be exemplified by a methane sulfonyl group, a p-toluenesulfonyl group, an o-nitrobenzenesulfonyl group, a trifluoromethane sulfonyl group, and the like.

[0039] The above-mentioned heteroaryl group can be exemplified by a furanyl group, a thienyl group, a pyrrolyl group, a pyridyl group, and the like containing a hetero atom in a ring as a ring constituent element.

[0040] When the compound represented by the above formula (1) has an acidic group such as a hydroxyl group, a sulfonic acid group, a carboxyl group, or the like, the acidic group can be in a free acid form or in a salt form.

[0041] When the above acidic group such as a hydroxyl group, a sulfonic acid group, a carboxyl group, or the like is in a salt form, the salt can be, for example, an alkali metal salt such as a lithium salt, a sodium salt, or a potassium salt; an alkaline earth metal salt such as a calcium salt; an ammonium salt such as an ammonium salt or a tetramethylammonium salt; or the like. When the compound represented by formula (1) has a plurality of the above acidic groups, all of the acidic groups can be in a free acid form, in a salt form, or in a mixture of a free acid form and a salt form. When a plurality of salts are present in the above acidic groups, the salts can be the same type of salt or different types of salt.

[0042] In the above compound represented by formula (1), R 1 to R 8 is preferably a sulfonic acid group or a salt thereof, more preferably at least two of R 1 to R 8 are sulfonic acid groups or salts thereof. In addition, at least one of R 1 to R 8 is a group selected from the group consisting of an alkyl group, an alkoxy group, a halogen group, and a carboxyl group or a salt thereof, and at least one is a sulfonic acid group or a salt thereof; more preferably at least one of R 1 to R 8 is selected from the group consisting of an alkyl group, an alkoxy group, and a halogen group, and at least two are sulfonic acid groups or salts thereof; and still more preferably at least one is selected from the group consisting of a methyl group, a methoxy group, and a chlorine group, and at least two are sulfonic acid groups or salts thereof. Of these, two of R 1 to R 8 are preferably sulfonic acid groups or salts thereof.

[0043] R 1 to R 8 , when the sulfonic acid group is in a salt form, the salt of the sulfonic acid group is preferably an ammonium salt or an alkali metal salt, and more preferably an ammonium sulfonate group (-SO3NH4) or a sodium sulfonate group (-SO3Na). In addition, when at least one of R 1 to R 8 is a group selected from the group consisting of an alkyl group, an alkoxy group, a halogen group, and a carboxyl group or a salt thereof, R 2 is preferably an alkyl group, an alkoxy group, a halogen group, or a carboxyl group or a salt thereof, more preferably an alkyl group, an alkoxy group, or a halogen group, and still more preferably a methyl group, a methoxy group, or a chlorine group.

[0044] In the above compound represented by formula (1), at least one of R 9 and R 10 is preferably a hydrogen atom, and more preferably at least one of R 9 and R 10each of R 9 and R 10 is a hydrogen atom. When one of R 9 and R 10 is a hydrogen atom, the other is preferably an alkyl group, more preferably a methyl group. In addition, at least one of R 1 to R 8 is a sulfonic acid group or a salt thereof; more preferably at least two of R 9 to R 10 are methyl groups, and at least two of R 1 to R 8 are sulfonic acid groups or salts thereof.

[0045] As the compound represented by the above formula (1), more preferable combinations of R 1 to R 10 can be mentioned: combinations in which any two of R 1 to R 8 are sulfonic acid groups, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which any two of R 1 to R 8 are salts of sulfonic acid groups, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which R 2 is a methyl group, R 1 and R 3 to R 8 are each a salt of a sulfonic acid group, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which R 2 is a methoxy group, R 1 and R 3 to R 8 are each a salt of a sulfonic acid group, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which R 1 to R 8 are each a methyl group and any two of them are a salt of a sulfonic acid group, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which R 2 and R 3 are each a methyl group, R 3 to R 8 are each a salt of a sulfonic acid group, the others are hydrogen atoms, R 9 and R 10 are each a hydrogen atom; combinations in which R 2 is a chlorine atom, R 1 and R 3 to R 8either of R 9 and R 10 is a hydrogen atom; R 2 is a carboxyl group, R 1 and R 3 are each a hydrogen atom; and R 8 is a hydrogen atom; or one of R 9 and R 10 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 1 and R 8 are each a hydrogen atom; or one of R 9 and R 10 is a methyl group and the other is a hydrogen atom, etc.

[0046] Among these, more preferable are: either of R 1 and R 8 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 9 and R 10 are each a hydrogen atom; or one of R 1 and R 8 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 9 and R 10 are each a hydrogen atom; or R 2 is a methyl group, R 1 and R 3 are each a hydrogen atom; or one of R 8 and R 9 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 10 and R 2 are each a hydrogen atom; or R 1 is a methoxy group, R 3 and R 8 are each a hydrogen atom; or one of R 9 and R 10 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 1 and R 8 are each a methyl group; or one of R 9 and R 10 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 1 and R 2 are each a hydrogen atom; or R 3 and R 8 are each a methyl group; or one of R 9 and R 10 is a salt of a sulfonic acid group, the other is a hydrogen atom, R 2 and R 1 are each a hydrogen atom; or R 3 is a chlorine atom, R 8either of R1and R2is a salt of a sulfonic acid group, the other is a hydrogen atom, R3 9 and R4 10 are each a hydrogen atom; R5 2 is a carboxyl group, R6 1 and R7 3 are each a hydrogen atom; and R8 8 to R9 9 either of R1and R2is a salt of a sulfonic acid group, the other is a hydrogen atom, R3 10 and R4 1 are each a hydrogen atom; and R5 8 to R9 9 either of R1and R2is a salt of a sulfonic acid group, the other is a hydrogen atom, R3 10 and R4

[0047] The compound represented by the above formula (1) can be used alone or in combination with two or more kinds. When used in combination with two or more kinds, they can be used in any ratio.

[0048] When the compound represented by the above formula (1) is an isomer such as a tautomer, a stereoisomer, or an optical isomer, it can be any isomer, or it can be a mixture of different isomers.

[0049] The solubility of the compound represented by the above formula (1) in water is preferably in the range of 0.1 mol / L or more and 5 mol / L or less, more preferably the lower limit is 0.2 mol / L and the upper limit is 3 mol / L. The solubility is the value (mol / L) when the compound represented by the above formula (1) is dissolved in the maximum amount in a sample aqueous solution prepared by adding a compound such as sodium bicarbonate to water containing the compound represented by the above formula (1) to adjust the alkalinity. Specifically, the absorbance of the prepared sample aqueous solution is measured, and the solubility is calculated from the calibration curve prepared from the absorbance at the maximum absorption wavelength.

[0050] [Electrolyte solution]

[0051] The carbon dioxide concentration device has an electrolyte solution containing the compound represented by the above formula (1) and water. Hereinafter, the electrolyte solution containing the compound represented by the above formula (1) and water is sometimes referred to simply as an "electrolyte solution".

[0052] The concentration of the compound represented by the above formula (1) in the electrolyte solution is not particularly limited, and is preferably in the range of 0.1 mol / L or more and 5 mol / L or less, more preferably the lower limit is 0.2 mol / L and the upper limit is 3 mol / L.

[0053] The electrolyte solution can further contain water as a solvent. For example, ion-exchange water, ultrapure water, or the like can be used as the water, and ultrapure water is more preferable. The water content in the electrolyte solution can be arbitrarily set, and is preferably 1% by mass or more and 99% by mass or less, more preferably 5% by mass or more and 90% by mass or less, and particularly preferably 10% by mass or more and 80% by mass or less.

[0054] The electrolyte solution can further contain a solute of an organic acid salt or an inorganic acid salt. Examples of the solute include lithium carbonate, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium chloride, ammonium sulfate, lithium acetate, sodium acetate, potassium acetate, ammonium acetate, lithium formate, sodium formate, potassium formate, ammonium formate, trilithium phosphate, lithium dihydrogen phosphate, trisodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, triammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, acetic acid, phosphoric acid, formic acid, glycine, alanine, valine, leucine, isoleucine, serine, asparagine, glutamine, arginine, and the like.

[0055] The pH of the electrolyte solution is preferably 5 or more and 12 or less, more preferably 5 or more and 11 or less, and still more preferably 5 or more and 10 or less, and particularly preferably 5 or more and 9 or less.

[0056] The method for preparing the electrolyte solution described above can include, for example, a method in which a compound represented by formula (1) and a compound represented by formula (2) below are dissolved in water as a solvent in the same molar amount as the compound represented by formula (1). The compound represented by formula (2) can be obtained by oxidizing the compound represented by formula (1).

[0057]

[0058] In formula (2) described above, R 1 to R 10 are the same as R 1 to R 10 defined in formula (1) described above. Further, a preferable combination of R 1 to R 10 is also the same as the compound represented by formula (1) described above. In addition, when one or both of R 9 and R 10 in formula (2) described above are hydrogen atoms, a compound from which the hydrogen atoms are removed is also included in the compound represented by formula (2). When the compound represented by formula (2) described above is contained in the electrolyte solution, R 1 to R 10 in the compound represented by formula (1) described above, R 1 to R 10 in the compound represented by formula (2) described above, respectively, can be the same or different, but are preferably the same, respectively.

[0059] Examples of oxidation methods for the compound shown in formula (1) include electrochemical oxidation methods and chemical oxidation methods. One example of an electrochemical oxidation method is to prepare an electrolyte A by dissolving the compound shown in formula (1) in a solution containing water or the like, using this as the positive electrode electrolyte, and using an electrolyte B containing the electrically reduced compound (described later) as the negative electrode electrolyte, and performing a charging reaction to obtain an electrolyte C containing the compound shown in formula (2). Furthermore, the charging reaction refers to the reaction in which electrolyte A is connected to the positive terminal of an external power source, and electrolyte B is connected to the negative terminal of the same external electrode, and current is passed through to obtain electrolyte C.

[0060] The aforementioned electrically reducing compounds are not particularly limited as long as they function as negative electrode materials. Examples include compounds with anthraquinone skeletons, compounds with naphthoquinone skeletons, compounds with benzoquinone skeletons, compounds with benzoquinone skeletons, compounds with benzoquinone skeletons, compounds with viologen skeletons, vanadium, chromium, zinc, copper, iron, etc. Compounds with anthraquinone skeletons or benzoquinone skeletons are preferred, and compounds with benzoquinone skeletons are especially preferred.

[0061] [First Electrode]

[0062] The first electrode is not particularly limited as long as it functions as a cathode, but a porous conductor is preferred. Examples of porous conductors include carbon felt or carbon sheets, carbon cloth, and carbon paper. For BET adsorption determination, a specific surface area of ​​1 m² is preferred for the porous conductor. 2 / g or more, preferably 30m 2 / g or more, and more preferably 100m 2 / g or more, preferably 500m 2 / g or more.

[0063] [Second Electrode]

[0064] The second electrode is not particularly limited as long as it functions as an anode, but a porous conductor is preferred. Examples of porous conductors include carbon felt or carbon sheets, carbon cloth, and carbon paper. For BET adsorption determination, a specific surface area of ​​1 m² is preferred for the porous conductor. 2 / g or more, preferably 30m 2 / g or more, and more preferably 100m 2 / g or more, preferably 500m 2 / g or more.

[0065] The first electrode and the aforementioned second electrode may each use the same type of material or porous conductor, or they may use different types of materials or porous conductors.

[0066] like Figure 1As shown, in the carbon dioxide concentration device 10 of the present embodiment, a voltage is applied using a direct current power source between the first electrode 1 and the second electrode 2. For example, the compound QH2 in formula (1) in which R 9 and R 10 is a hydrogen atom is used as the mediator, and when a voltage is applied, the compound QH2 is oxidized in the second electrode 2 to produce the compound Q and release protons (H + ) into the electrolyte, so the pH of the electrolyte 3 on the second electrode 2 side becomes relatively low. In addition, by the voltage application, the compound Q is reduced in the first electrode 1 to become the compound QH2, so the pH of the electrolyte 3 on the first electrode 1 side becomes relatively high. If the pH of the electrolyte 3 becomes relatively high, the carbon dioxide introduced together with nitrogen, oxygen, or the like is easily dissolved in water, which is the solvent of the electrolyte 3, due to the properties of carbon dioxide, and bicarbonate ions are dissociated. The dissociated bicarbonate ions move to the second electrode 2 side where the pH is relatively low, and carbon dioxide and water are generated from the bicarbonate ions and protons, so the carbon dioxide is concentrated. As described above, by using the difference in solubility of carbon dioxide due to the pH, a high concentration of carbon dioxide can be obtained on the second electrode side, and a carbon dioxide concentration device that exhibits the characteristic of being able to selectively concentrate carbon dioxide can be realized.

[0067] The carbon dioxide concentration device 10 of the present embodiment preferably further includes a separator 4 between the first electrode 1 and the second electrode 2, and two types of electrolytes (3, 3) can be used with the separator 4. At this time, the carbon dioxide concentration device 10 includes a first electrolyte (not shown) that is filled between the first electrode 1 and the separator 4 and exists in contact with the first electrode 1, and a second electrolyte (not shown) that is filled between the second electrode 2 and the separator 4 and exists in contact with the second electrode 2. The first electrolyte and the second electrolyte can be the same electrolyte, or different electrolytes from each other. When the first electrode 1 and the second electrode 2 use different electrolytes, for example, the above-described electrolyte A containing the compound shown in formula (1) and the above-described electrolyte B containing the electrically reducing compound can be combined as the respective electrolytes.

[0068] The separator can be, for example, a cellulose porous membrane, a polyolefin porous membrane represented by polyethylene and polypropylene, a porous membrane of polyester, aliphatic polyamide, aromatic polyamide, and nonwoven fabric, and the porosity of the separator is preferably high. The separator can be either an anion exchange membrane or a cation exchange membrane.

[0069] The carbon dioxide concentration device of the present embodiment can further include an external power source, and the external power source is preferably a direct current power source.

[0070] According to the above embodiments, the present application relates to the following [1] to [7].

[0071] [1] A carbon dioxide concentration device including:

[0072] a first electrode belonging to a cathode;

[0073] a second electrode belonging to an anode disposed apart from the aforementioned first electrode; and

[0074] at least one electrolyte filled between the aforementioned first electrode and the aforementioned second electrode and present in contact with the aforementioned first electrode and the aforementioned second electrode; wherein,

[0075] at least one of the aforementioned electrolyte contains a compound represented by the following formula (1) or a salt thereof, and water.

[0076]

[0077] (In formula (1), R 1 to R 10 each independently represent a hydrogen atom, an alkyl group, a hydroxyl group or a salt thereof, an alkoxy group, a nitro group, an amino group, a mercapto group, a cyano group, a halogen group, an aryl group, a sulfonic acid group or a salt thereof, a carboxyl group or a salt thereof, a carbonyl group, a sulfonyl group, or a heteroaryl group.)

[0078] [2] The carbon dioxide concentration device according to the above [1], wherein, in the aforementioned formula (1), at least one of R 1 to R 8 is a sulfonic acid group or a salt thereof.

[0079] [3] The carbon dioxide concentration device according to the above [1], wherein, in the aforementioned formula (1), at least two of R 1 to R 8 are sulfonic acid groups or salts thereof.

[0080] [4] The carbon dioxide concentration device according to the above [2], wherein, in the aforementioned formula (1), at least one of R 1 to R 8 is a group selected from the group consisting of an alkyl group, an alkoxy group, a halogen group, and a carboxyl group or a salt thereof.

[0081] [5] The carbon dioxide concentration device according to any one of the above [1] to [4], wherein a separator is further provided between the aforementioned first electrode and the aforementioned second electrode.

[0082] [6] The carbon dioxide concentration device according to the above [5], comprising: a first electrolyte filled between the aforementioned first electrode and the aforementioned separator and present in contact with the aforementioned first electrode, and a second electrolyte filled between the aforementioned second electrode and the separator and present in contact with the aforementioned second electrode, wherein the aforementioned first electrolyte contains a compound represented by the aforementioned formula (1) or a salt thereof, and water.

[0083] [7] The carbon dioxide concentration device according to claim 6, wherein the first electrolyte and the second electrolyte are different from each other.

[0084] [Embodiment]

[0085] The present application is further explained in detail by the following examples, but the present application is not limited to these. In addition, unless otherwise specified, room temperature is in the range of 20°C ± 5°C.

[0086] [Synthesis Example 1]

[0087] The 2,3-dichloroquinoxaline 25.2 parts and o-phenylenediamine 13.7 parts were dissolved in dimethylformamide (DMF) 500 parts and heated to 120°C. After maintaining 120°C and stirring the resulting solution for 3 hours, it was cooled to room temperature, and the precipitate was separated by filtration under reduced pressure, whereby a wet cake 50 parts was obtained. To the wet cake was added acetone 200 parts and stirred for 30 minutes, and the precipitate was separated by filtration under reduced pressure. The resulting wet cake was dried at 80°C for 1 day, whereby 23.4 parts of the tetraazapentacene compound represented by the following formula (1-1) was obtained.

[0088]

[0089] [Synthesis Example 2]

[0090] The tetraazapentacene compound represented by formula (1-1) obtained in the above Synthesis Example 1, 2.5 parts, was added to 15% fuming sulfuric acid 30 parts cooled to 5°C, and then stirred at 25°C for 5 hours. After the completion of the reaction, the reaction solution was dropped into ice water 100 parts, and stirred at 25°C for 30 minutes, and the precipitate was separated by filtration under reduced pressure, whereby a wet cake 10 parts was obtained. To the wet cake was added water 20 parts and stirred for 60 minutes, and the precipitate was separated by filtration under reduced pressure. To the resulting precipitate was added water 40 parts, and while stirring, ammonia water was dropped and adjusted to pH 8.0 to 9.0, and then the solvent was distilled off, and dried at 80°C for 1 day, whereby 3.8 parts of the tetraazapentacene compound represented by the following formula (1-2) was obtained.

[0091]

[0092] [Synthesis Example 3]

[0093] While stirring 1,2-phenylenediamine 17.6 parts and 2,5-dihydroxy-1,4-benzoquinone 25 parts in water 3000 parts, it was heated to reflux for 5 hours and 30 minutes, and then cooled to room temperature, and further stirred overnight. From the resulting suspension, a black wet cake was separated by filtration, and further washed with water. The wet cake was dried under reduced pressure at 80°C, whereby a wet cake 103.2 parts containing 0.163 moles of the compound represented by the following formula (1-3) was obtained.

[0094]

[0095] [Synthesis Example 4]

[0096] The wet cake obtained in Synthesis Example 3 above, 51.2 parts, and 1,8- diazabicyclo[5,4,0]undec-7-ene, 36.6 parts, were dissolved in dimethylformamide, 410 parts, and 1,3-propane sultone, 30.2 parts, was added thereto, followed by heating to 120°C and stirring for 3 hours. Thereafter, the temperature was cooled to room temperature, and 28% aqueous ammonia, 24.7 parts, was added to the resulting solution and stirred for 30 minutes. The resulting reaction solution was poured into acetone, 3.0 L, and the precipitated solid was separated by filtration, whereby a wet cake was obtained. This was dissolved in water, 70 parts, and 25% aqueous sodium hydroxide solution, 10 parts, was added thereto, followed by further pouring into ethanol, 1.5 L, and the precipitated solid was separated by filtration, whereby a red wet cake was obtained. This was dried at 80°C under reduced pressure, whereby the compound represented by the following formula (1-4), 34.8 parts, was obtained.

[0097]

[0098] [Example 1]

[0099] The tetraazafused tetraphene compound represented by the above formula (1-2) was dissolved in an aqueous ammonium bicarbonate solution (Showa Denko K.K. product, Kanto grade) (1.0 mol / L) so as to have a concentration of 0.1 mol / L, to thereby prepare electrolyte 1. In addition, the compound represented by the above formula (1-4) was dissolved in the above aqueous ammonium bicarbonate solution so as to have a concentration of 0.1 (mol / L), to thereby prepare electrolyte 2. As a separator, an ion exchange membrane (Sigma-Aldrich JAPAN K.K. product, Nafion (registered trademark) NRE-212) was used, and as an electrode, carbon felt (Toyo Roki Co., Ltd. product, AAF304ZS, 10 mm x 50 mm x 4 mm) was used. The above carbon felt was inserted into a hole of 50 mm x 10 mm which was left in the center portion of a silicon gasket (80 mm x 30 mm x 3 mm), to thereby assemble in the order of current collector / electrode / separator / electrode / current collector. As an electrolyte, 10 ml of each of the prepared electrolyte 1 and electrolyte 2 was added to each sample vial, and a peristaltic pump was used to fill the electrolyte into the inside of the cell through the separator. Using a multichannel electrochemical measurement system (Hokuto Denko Corporation product, HZ-Pro), electrolyte 1 was oxidized at a fixed current of 100 mA and a upper limit voltage of 1.3 V, to thereby prepare electrolyte 3. The prepared electrolyte 3 and the same amount of electrolyte 1 were mixed, to thereby prepare electrolyte 4. The pH of electrolyte 4 was measured with a benchtop pH meter (HORIBA, Ltd. product, F-73), and the pH was 8.14.

[0100] As a separator, a cellulose porous membrane (REPLIGEN Corporation product, Spectra / Por TM6, MWCO = 1 kD), the first and second electrodes each used carbon felt (AAF304ZS, 10 mm x 50 mm x 4 mm, manufactured by Toyobo Co., Ltd.), and the carbon felt was inserted into a hole of 50 mm x 10 mm left empty in the center of a silicon gasket (80 mm x 30 mm x 3 mm) to be combined in the order of current collector / first electrode / septum / second electrode / current collector. As the electrolyte, 10 ml of the electrolyte 4 was added to each sample bottle, and a peristaltic pump was used to fill the electrolyte inside the cell through the septum. A multichannel electrochemical measurement system (HZ-Pro, manufactured by Hokuto Denko Corp.) was used to pass a current at a fixed current of 100 mA and a limit voltage of 0.5 V. The pH of the electrolyte on the anode (second electrode) side after the reaction was 7.86, and the pH of the electrolyte on the cathode (first electrode) side was 8.41.

[0101] [Table 1]

[0102] Example Pre-reaction pH Post-reaction pH (anode) Post-reaction pH (cathode) 1 8.14 7.86 8.41

[0103] As shown in Table 1 above, the carbon dioxide concentration device produced in Example 1 can generate a pH gradient at the anode and the cathode by passing a current, and it is known to have a characteristic of selectively concentrating carbon dioxide.

[0104] [Synthesis Example 5]

[0105] The 2,3-dichloroquinoxaline 101 parts and 3,4-diaminotoluene 62.0 parts were dissolved in 1-butanol 405 parts and heated to 114°C. After maintaining 114°C and stirring for 5 hours, it was cooled to room temperature, and 8% sodium bicarbonate aqueous solution 542 parts was added to the resulting solution and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, washed with methanol 240 parts, and thereby wet cake 243 parts was obtained. Methanol 317 parts was added to the wet cake and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, washed with methanol 240 parts. Water 300 parts was added to the resulting wet cake and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, washed with water 300 parts, and thereby wet cake 295 parts was obtained. The resulting wet cake was dried at 80°C for 15 hours, and thereby tetraazapentacene compound represented by the following formula (1-5) 88.0 parts was obtained.

[0106]

[0107] [Synthesis Example 6]

[0108] To 150 parts of 15% oleum cooled to 5°C was added 15.0 parts of the tetraazapentacene compound represented by formula (1-5) obtained in Synthetic Example 5 above, and then stirred at 25°C for 15 hours. After completion of the reaction, the reaction solution was dropped into 360 parts of ice water, and stirred at 25°C for 30 minutes, and then the precipitate was separated by filtration under reduced pressure, whereby 123 parts of a wet cake was obtained. To the wet cake was added 125 parts of water and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure. To 108 parts of the obtained wet cake was added 110 parts of water and stirred for 60 minutes, and then the precipitate was separated by filtration under reduced pressure. To the obtained precipitate was added 150 parts of water, and while stirring, sodium hydroxide was added and adjusted to pH 6.5 to 7.5, and then 0.81 parts of CARBORAFIN was added and stirred at 50°C for 1 hour. After the dispersion was cooled to room temperature, it was filtered with RADIOLITE, and the solvent of the obtained filtrate was distilled off, whereby 22.3 parts of a yellow solid was obtained. The yellow solid was dissolved in 220 parts of water, dropped into 1100 parts of 2-propanol, and the precipitate was separated by filtration under reduced pressure. While the obtained wet cake was heated at 80°C for 1 day, it was dried under reduced pressure, whereby 18.5 parts of the tetraazapentacene compound represented by formula (1-6) shown below was obtained.

[0109]

[0110] [Synthetic Example 7]

[0111] To 40.5 parts of 1-butanol was dissolved 10.0 parts of 2,3-dichloroquinoxaline and 6.84 parts of 4,5-dimethylphenylene-1,2-diamine, and heated to 114°C. After maintaining at 114°C and stirring the obtained solution for 7 hours, it was cooled to room temperature, and the precipitate was separated by filtration under reduced pressure, and washed with 105 parts of methanol, whereby 15 parts of a wet cake was obtained. To the wet cake was added 35 parts of methanol and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 35 parts of methanol. To the obtained wet cake was added 105 parts of water and stirred, and 15 parts of 25% aqueous sodium hydroxide solution was added and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 105 parts of water, whereby 15 parts of a wet cake was obtained. To the wet cake was added 35 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. To the obtained wet cake was added 70 parts of 25% aqueous sodium hydroxide solution and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. The obtained wet cake was dried at 80°C for 15 hours, whereby 6.51 parts of the tetraazapentacene compound represented by formula (1-7) shown below was obtained.

[0112]

[0113] [Synthetic Example 8]

[0114] The tetraazapentacene compound represented by formula (1-7) obtained in Synthesis Example 7 above, 4.00 parts, was added to 15% oleum, 40 parts, cooled to 5°C, and then stirred at 25°C for 66 hours. After further stirring at 60°C for 8 hours, the mixture was cooled to 25°C, 15% oleum, 40 parts, was added to the resulting solution, and stirred for 6 hours. After completion of the reaction, the reaction solution was dropped into ice water, 125 parts, and stirred at 25°C for 30 minutes, and then the precipitate was separated by filtration under reduced pressure. To the resulting wet cake, 60 parts, water, 60 parts, was added and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure. To the resulting wet cake, 41 parts, water, 80 parts, was added, and while stirring, 25% aqueous sodium hydroxide solution was added and adjusted to pH 6.5 to 7.5, and then CARBORAFIN, 0.21 part, was added, and stirred at 50°C for 1 hour. After cooling the dispersion to room temperature, it was filtered using RADIOLITE, and the solvent of the resulting filtrate was distilled off, thereby obtaining a yellow solid, 7.92 parts. The yellow solid was dissolved in water, 80 parts, and dropped into 2-propanol, 400 parts, and the precipitate was separated by filtration under reduced pressure. While heating the resulting wet cake at 80°C for 1 day, it was dried under reduced pressure, thereby obtaining a tetraazapentacene compound represented by formula (1-8) shown below, 6.07 parts.

[0115]

[0116] [Synthesis Example 9]

[0117] The 2,3-dichloroquinoxaline, 10.0 parts, and 3,4-diaminobenzoic acid, 7.64 parts, were dissolved in 1-butanol, 40.5 parts, and heated to 114°C. The resulting solution was maintained at 114°C and stirred for 24 hours, and then cooled to room temperature, and the precipitate was separated by filtration under reduced pressure, and washed with methanol, 105 parts, thereby obtaining a wet cake, 20 parts. To the wet cake, methanol, 35 parts, was added and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure, and washed with methanol, 35 parts. To the resulting wet cake, water, 105 parts, was added and stirred, and 1M aqueous sodium hydroxide solution, 17.4 parts, was added and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with water, 180 parts. To the resulting wet cake, water, 60 parts, was added and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure. The resulting wet cake was dried at 80°C for 15 hours, thereby obtaining a tetraazapentacene compound represented by formula (1-9) shown below, 9.19 parts.

[0118]

[0119] [Synthesis Example 10]

[0120] To 50 parts of 15% oleum cooled to 5°C was added 5.00 parts of the tetraazapentacene compound represented by formula (1-9) obtained in Synthetic Example 9, and then stirred at 25°C for 5 hours. After completion of the reaction, the reaction solution was dropped into 121 parts of ice water, and stirred at 25°C for 30 minutes, and then the precipitate was separated by filtration under reduced pressure, whereby 27.5 parts of a wet cake was obtained. To the wet cake was added 30 parts of water and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure. To the obtained wet cake was added 25 parts of water and stirred for 1 hour, and then the precipitate was separated by filtration under reduced pressure. To 18.6 parts of the obtained wet cake was added 53 parts of water, and while stirring, 25% sodium hydroxide aqueous solution was added and adjusted to pH 6.5 to 7.5, and then 0.33 parts of CARBORAFIN was added and stirred at 50°C for 1 hour. After the dispersion was cooled to room temperature, it was filtered with RADIOLITE, and the obtained filtrate was dropped into 1100 parts of 2-propanol, and the precipitate was separated by filtration under reduced pressure. While the obtained wet cake was heated at 80°C for 1 day, it was dried under reduced pressure, whereby 2.60 parts of the tetraazapentacene compound represented by formula (1-10) shown below was obtained.

[0121]

[0122] [Synthetic Example 11]

[0123] To 40.5 parts of 1-butanol was dissolved 10.0 parts of 2,3-dichloroquinoxaline and 7.16 parts of 4-chlorostilbene-1,2-diamine, and heated to 114°C. After the obtained solution was maintained at 114°C and stirred for 7 hours, it was cooled to room temperature, and the precipitate was separated by filtration under reduced pressure, and washed with 105 parts of methanol, whereby a wet cake was obtained. To the wet cake was added 35 parts of methanol and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 35 parts of methanol. To the obtained wet cake was added 105 parts of water and stirred, and 15 parts of 25% sodium hydroxide aqueous solution was added and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 105 parts of water, whereby a wet cake was obtained. To the obtained wet cake was added 35 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. The obtained wet cake was dried at 80°C for 15 hours, whereby 10.3 parts of the tetraazapentacene compound represented by formula (1-11) shown below was obtained.

[0124]

[0125] [Synthetic Example 12]

[0126] To 80 parts of 15% oleum cooled to 5°C was added 8.00 parts of the tetraazapentacene compound represented by formula (1-11) obtained in Synthetic Example 11 above, and then stirred at 25°C for 20 hours. The resulting solution was further stirred at 90°C for 6 hours, and the reaction solution was allowed to cool to 25°C and dropped into 193 parts of ice water. After stirring at 25°C for 30 minutes, the precipitate was separated by filtration under reduced pressure, and thereby 56.0 parts of a wet cake was obtained. To the wet cake was added 60 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. To the resulting wet cake was added 45 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. To 32.4 parts of the resulting wet cake was added 113 parts of water, and while stirring, 25% sodium hydroxide aqueous solution was added and adjusted to pH 6.5 to 7.5, and then CARBORAFIN 0.81 parts was added and stirred at 50°C for 1 hour. After the dispersion was allowed to cool to room temperature, it was filtered with RADIOLITE, and the resulting filtrate was dropped into 600 parts of 2-propanol, and the precipitate was separated by filtration under reduced pressure. While the resulting wet cake was heated at 80°C for 1 day, it was dried under reduced pressure, and thereby 9.97 parts of the tetraazapentacene compound represented by formula (1-12) shown below was obtained.

[0127]

[0128] [Synthetic Example 13]

[0129] To 40.5 parts of 1-butanol was dissolved 10.0 parts of 2,3-dichloroquinoxaline and 6.94 parts of 4-chlorostilbene-1,2-diamine, and heated to 114°C. After the resulting solution was maintained at 114°C and stirred for 24 hours, it was allowed to cool to room temperature, and then 25% sodium hydroxide aqueous solution was added to the resulting solution and adjusted to pH 6.5 to 7.5, and then stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 105 parts of methanol, and thereby 22 parts of a wet cake was obtained. To the wet cake was added 35 parts of methanol and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 105 parts of methanol. To the resulting wet cake was added 35 parts of water and stirred for 1 hour. The precipitate was separated by filtration under reduced pressure, and washed with 35 parts of water, and thereby 26.8 parts of a wet cake was obtained. The resulting wet cake was dried at 80°C for 15 hours, and thereby 10.4 parts of the tetraazapentacene compound represented by formula (1-13) shown below was obtained.

[0130]

[0131] [Synthetic Example 14]

[0132] To 80 parts of 15% oleum cooled to 5°C was added 8.00 parts of the tetraazapentacene compound represented by formula (1-13) obtained in Synthetic Example 13 above, and then stirred at 25°C for 5 hours. The reaction solution was dropped into 193 parts of ice water, and after stirring at 25°C for 30 minutes, the precipitate was separated by filtration under reduced pressure, and thus 28.8 parts of a wet cake was obtained. To the wet cake was added 30 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. To the obtained wet cake was added 25 parts of water and stirred for 1 hour, and the precipitate was separated by filtration under reduced pressure. To 21.5 parts of the obtained wet cake was added 108 parts of water, and while stirring, 25% sodium hydroxide aqueous solution was added and adjusted to pH 6.5 to 7.5, and then 0.41 parts of CARBORAFIN was added and stirred at 50°C for 1 hour. After the dispersion was cooled to room temperature, it was filtered with RADIOLITE, and the obtained filtrate was dropped into 540 parts of 2-propanol, and the precipitate was separated by filtration under reduced pressure. While the obtained wet cake was heated at 80°C for 1 day, it was dried under reduced pressure, and thus 8.73 parts of the tetraazapentacene compound represented by formula (1-14) below was obtained.

[0133]

[0134] [Synthetic Example 15]

[0135] To 60 parts of sulfuric acid was added 20 parts of gallic acid and stirred, and then stirred at 105°C for 3 hours. The reaction solution was cooled to 50°C and poured into 150 parts of ice water, and the obtained suspension was stirred for 1 hour. After stirring, the suspension was separated by filtration, and thus a wet cake was obtained. The wet cake was added to 150 parts of cold water, and after stirring for 30 minutes, the suspension was separated by filtration, and thus a wet cake was obtained. The wet cake was added little by little to 150 parts of 5% sodium bicarbonate aqueous solution, and after stirring for 1 hour, the suspension was separated by filtration, and thus a wet cake was obtained. The wet cake was dried with a hot air drier at 80°C, and thus 12.4 parts of the compound represented by formula (1-15) below was obtained.

[0136]

[0137] [Synthetic Example 16]

[0138] To 45 parts of water was added 15 parts of the compound represented by formula (1-15) above and stirred, and the pH of the solution was adjusted to 9.5 to 10.0 with 25% sodium hydroxide aqueous solution, and then warmed to 60°C. To the obtained solution was dropped 20 parts of propane sulfone lactone over 2 hours, and after the dropping was completed, stirred at 60°C for 4 hours. During this time, the pH of the solution was maintained at pH 10.0 to 10.5 with 25% sodium hydroxide aqueous solution. To the obtained reaction solution was added 500 parts of methanol, and stirred at 20 to 25°C for 2 hours. After stirring, the precipitated solid was separated by filtration, and thus 40.8 parts of a wet cake was obtained. The wet cake was dried with a hot air drier at 80°C, and thus 9.2 parts of the compound represented by formula (1-16) below was obtained.

[0139]

[0140] [Example 2]

[0141] The tetraazapentacene compound represented by the above formula (1-2) in Example 1 was changed to the tetraazapentacene compound represented by the above formula (1-6), the compound represented by the above formula (1-4) was changed to the compound represented by the above formula (1-16), and ammonium bicarbonate was changed to sodium bicarbonate, and electrolyte 5 was prepared in the same manner as electrolyte 4 of Example 1, except for these changes. An electrochemical cell was prepared in the same manner as Example 1, and a current was passed through the cell in the same manner as Example 1. The pH of the electrolyte before the reaction was 9.161, the pH of the electrolyte on the anode side after the reaction was 8.699, and the pH of the electrolyte on the cathode side after the reaction was 9.456.

[0142] [Example 3]

[0143] The tetraazapentacene compound represented by the above formula (1-6) in Example 2 was changed to the tetraazapentacene compound represented by the above formula (1-8), and electrolyte 6 was prepared in the same manner as electrolyte 5 of Example 2, except for this change. An electrochemical cell was prepared in the same manner as Example 1, and a current was passed through the cell in the same manner as Example 1. The pH of the electrolyte before the reaction was 8.967, the pH of the electrolyte on the anode side after the reaction was 8.782, and the pH of the electrolyte on the cathode side after the reaction was 9.124.

[0144] [Example 4]

[0145] The tetraazapentacene compound represented by the above formula (1-6) in Example 2 was changed to the tetraazapentacene compound represented by the above formula (1-10), and the concentration was changed to 0.01 M, and electrolyte 7 was prepared in the same manner as electrolyte 5 of Example 2, except for these changes. An electrochemical cell was prepared in the same manner as Example 1, and a current was passed through the cell in the same manner as Example 1. The pH of the electrolyte before the reaction was 8.596, the pH of the electrolyte on the anode side after the reaction was 8.555, and the pH of the electrolyte on the cathode side after the reaction was 8.632.

[0146] [Example 5]

[0147] The tetraazapentacene compound represented by the above formula (1-6) in Example 2 was changed to the tetraazapentacene compound represented by the above formula (1-12) and the concentration thereof was changed to 0.01 M, the concentration of sodium bicarbonate was changed to 0.5 M, and electrolyte 8 was prepared in the same manner as electrolyte 5 of Example 2 except for these. An electrochemical cell was prepared in the same manner as Example 1 and a current was passed in the same manner as Example 1. The pH of the electrolyte before the reaction was 8.856, the pH of the electrolyte on the anode side after the reaction was 8.794, and the pH of the electrolyte on the cathode side after the reaction was 8.935.

[0148] [Example 6]

[0149] The tetraazapentacene compound represented by the above formula (1-6) in Example 2 was changed to the tetraazapentacene compound represented by the above formula (1-14) and the concentration thereof was changed to 0.05 M, the concentration of sodium bicarbonate was changed to 0.5 M, and electrolyte 9 was prepared in the same manner as electrolyte 5 of Example 2 except for these. An electrochemical cell was prepared in the same manner as Example 1 and a current was passed in the same manner as Example 1. The pH of the electrolyte before the reaction was 8.358, the pH of the electrolyte on the anode side after the reaction was 7.674, and the pH of the electrolyte on the cathode side after the reaction was 8.882.

[0150] The results of Examples 2 to 6 are shown in Table 2.

[0151] [Table 2]

[0152] Example Pre-reaction pH Post-reaction pH (anode) Post-reaction pH (cathode) 2 9.161 8.699 9.456 3 8.967 8.782 9.124 4 8.596 8.555 8.632 5 8.856 8.794 8.935 6 8.358 7.674 8.882

[0153] As shown in Table 2, the carbon dioxide concentration device prepared in Examples 2 to 6 can generate a pH gradient at the anode and the cathode by passing a current, and it is understood that the device has a property of selectively concentrating carbon dioxide.

[0154] [Redox resistance evaluation 1]

[0155] An electrolyte 10 was prepared by dissolving a tetraazapentacene compound represented by the above formula (1-2) in an aqueous solution of sodium bicarbonate (TOSOH Corporation, industrial product) at a concentration of 0.1 mol / L. The electrolyte 10 was added to a voltammetry sample bottle (BAS Corporation, No. 001056), and a voltammetry Teflon® cap (BAS Corporation, 012671) was attached. A Pt counter electrode (BAS Corporation, No. 002222), a GCE glassy carbon electrode (BAS Corporation, 6.0 x 3.0 mm, No. 002012), and a saturated KCl silver chloride reference electrode (BAS Corporation, No. 013503) were fixed to the Teflon® cap so as to be immersed in the electrolyte 10. TM TM ​The electrolyte was measured using cyclic voltammetry with a multichannel electrochemical measurement system (HZ-Pro, manufactured by Beidou Electric Co., Ltd.). Measurements were performed with a potential scan range of -500 mV to 700 mV and a scan rate of 100 mV / sec. The cyclic voltammetry results for the first cycle of electrolyte 10 are shown in the figure. Figure 1 .like Figure 1 As shown, symmetrical oxidation and reduction waves were observed, indicating that an electrochemically stable redox reaction was generated.

[0156] [Comparative Example 1]

[0157] The tetraaza-condensed tetraphenyl compound shown in formula (1-6) of Example 2 was replaced with the compound shown in formula (1-17), except that electrolyte 11 was prepared in the same manner as electrolyte 5 of Example 2. An electrochemical cell identical to that of Example 1 was fabricated and operated with the same current as in Example 1. The pH of the electrolyte before the reaction was 7.690, the pH of the electrolyte on the anode side after the reaction was 7.519, and the pH of the electrolyte on the cathode side was 8.207.

[0158]

[0159] [Redox Resistance Evaluation 2]

[0160] The tetraaza-condensed tetraphenyl compound shown in formula (1-2) of the above redox resistance evaluation 1 is replaced with the compound shown in formula (1-17) above, and the electrolyte 12 is prepared in the same manner.

[0161] Electrolyte 10 was changed to electrolyte 12, and the potential scan range was changed to -1000 to 1400 mV. Otherwise, the same procedures as in redox resistance evaluation 1 were performed, and cyclic voltammetry was used for determination. The cyclic voltammetry diagram for the first cycle of electrolyte 12 is shown below. Figure 2 .like Figure 2 As shown, although multiple oxidation waves were observed, almost no reduction waves were observed, suggesting that the compound shown in the following formula (1-17) decomposes after oxidation.

[0162] As can be seen from the above results, the tetraaza-condensed tetrabenzene compound shown in formula (1-2) not only has the characteristic of selectively concentrating carbon dioxide, but also has high stability relative to redox reactions. As a result, the carbon dioxide concentration device using the electrolyte containing the compound shown in formula (1) has excellent stability.

[0163] [Industrial applicability]

[0164] The carbon dioxide concentration apparatus of the present invention provides the characteristic of separating and recovering carbon dioxide from the atmosphere and factory exhaust.

[0165] Explanation of reference numerals in the attached figures

[0166] 1. First electrode (cathode)

[0167] 2. Second electrode (anode)

[0168] 3 Electrolyte

[0169] 4 diaphragms

[0170] 10. Carbon dioxide concentration unit.

Claims

1. A carbon dioxide concentration device comprising: a first electrode belonging to a cathode; a second electrode belonging to an anode disposed apart from the first electrode; and at least one electrolyte filled between the first electrode and the second electrode and present in contact with the first electrode and the second electrode, wherein at least one of the electrolytes contains a compound represented by the following formula (1) or a salt thereof, and water, and wherein the device further comprises a separator between the first electrode and the second electrode. Formula (1) ###0001### wherein R1 represents a hydrogen atom or a hydrocarbon group, R2 represents a hydrogen atom or a hydrocarbon group, and R3 represents a hydrogen atom or a hydrocarbon group.

2. The carbon dioxide concentration device according to claim 1, wherein the first electrolyte contains the compound represented by the formula (1) or the salt thereof, and water.

3. The carbon dioxide concentration device according to claim 1, wherein the first electrolyte and the second electrolyte are mutually different electrolytes.

4. The carbon dioxide concentration device according to claim 1, wherein the first electrolyte and the second electrolyte are mutually different electrolytes, and the first electrolyte contains the compound represented by the formula (1) or the salt thereof, and water.

5. The carbon dioxide concentration device according to claim 1, wherein the first electrolyte and the second electrolyte are mutually different electrolytes, and the second electrolyte contains the compound represented by the formula (1) or the salt thereof, and water. ， In formula (1), R 1 to R 10 each independently represents a hydrogen atom, an alkyl group, a hydroxyl group or a salt thereof, an alkoxy group, a nitro group, an amino group, a mercapto group, a cyano group, a halogen group, an aryl group, a sulfonic acid group or a salt thereof, a carboxyl group or a salt thereof, a carbonyl group, a sulfonyl group, or a heteroaryl group.

2. The carbon dioxide concentration device according to claim 1, wherein, In the aforementioned formula (1), R 1 at least one of R 8 is a sulfonic acid group or a salt thereof.

3. The carbon dioxide concentration device according to claim 1, wherein, In the aforementioned formula (1), R 1 at least 2 of R 8 to R are a sulfonic acid group or a salt thereof.

4. The carbon dioxide concentration device according to claim 2, wherein, In the aforementioned formula (1), R 1 at least one of R 8 is a group selected from the group consisting of an alkyl group, an alkoxy group, a halogen group, and a carboxyl group or a salt thereof.

5. The carbon dioxide concentration device according to any one of claims 1 to 4, wherein, ​ 6. The carbon dioxide concentration device according to claim 5, comprising a first electrolyte filled between the first electrode and the separator and in contact with the first electrode, and a second electrolyte filled between the second electrode and the separator and in contact with the second electrode, wherein, ​ 7. The carbon dioxide concentration device of claim 6, wherein, ​

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