Absorption or desorption agent of carbon dioxide
A carbon dioxide absorption agent formed by reacting polyallylamine with a specific compound enhances absorption capacity and allows for repeated use, addressing the limitations of existing absorbents by increasing capacity and eliminating odors.
Patent Information
- Application Number
- JP2024010598
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-01-26
- Publication Date
- 2025-08-07
AI Technical Summary
Existing carbon dioxide absorbents and desorbents, such as low-molecular-weight amine compounds, have limited carbon dioxide absorption capacity and can produce foul odors due to evaporation, and they are not designed for repeated use.
A carbon dioxide absorption or desorption agent is created by reacting polyallylamine with a compound represented by general formula (1), forming specific functional groups that enhance carbon dioxide absorption capacity and allow for repeated use without foul odors.
The reaction product exhibits a significantly higher carbon dioxide absorption capacity, up to 17 times that of polyallylamine, and can be repeatedly used for carbon dioxide absorption and desorption without odor issues.
Smart Images
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Abstract
Description
[Technical Field]
[0001] The present invention relates to a carbon dioxide absorption or desorption agent. [Background technology]
[0002] The use of amine compounds as carbon dioxide absorbents, desorbents, etc. has been investigated. For example, Patent Document 1 describes a method for adsorbing gases, particularly acidic gases, onto a monodisperse spherical aminomethylated polymer. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-52340 Summary of the Invention [Problem to be solved by the invention]
[0004] An object of the present invention is to provide a carbon dioxide absorption or desorption agent having a sufficiently large carbon dioxide absorption capacity. [Means for solving the problem]
[0005] The present invention provides a carbon dioxide absorption or desorption agent as set forth in the following [1] to [4].
[0006] [1] A carbon dioxide absorber or desorber comprising a reaction product of polyallylamine and a compound represented by the following general formula (1), which bonds to at least one amino group of the 3-aminopropylene repeating unit constituting the polyallylamine:
[0007] [ka] [In the formula, n is a number from 0 to 5, A is a group bonding to the amino group, and R each independently represents a halogen atom, a hydroxyl group, or a hydrocarbon group, and when two or more hydrocarbon groups are present as R, they may be joined together to form a condensed aromatic ring.]
[0008] In the general formula (1), -(R) n means that n Rs are bonded to the benzene ring.
[0009] The reaction product has a sufficiently large carbon dioxide absorption capacity, and the carbon dioxide absorption capacity determined by the carbon dioxide absorption capacity evaluation described below can be, for example, about 3 to 17 times that of polyallylamine.
[0010] Furthermore, carbon dioxide absorbents that use low-molecular-weight amine compounds such as monoethanolamine may produce a foul odor due to the evaporation of the low-molecular-weight amine compounds, but since the reaction product is a polymer, the foul odor can be reduced.
[0011] Furthermore, since the reactant can repeatedly absorb and desorb carbon dioxide, the carbon dioxide absorbing or desorbing agent can be used repeatedly.
[0012] [2] The absorbent or desorbent according to [1], wherein the bond between the polyallylamine and the compound represented by general formula (1) forms at least one group selected from the group consisting of -NH-CO-, -NH-CO-NH-, -NH-CH2-C(OH)H-, and -NH-CH2-CH2-.
[0013] The formation of such groups ensures sufficient carbon dioxide absorption capacity. Furthermore, since such groups can be formed relatively easily from amino groups, they are advantageous for increasing the yield of the reaction product. A group containing -NH-CO- can be formed when A is a group having a carboxy group or an acyl halide group, a group containing -NH-CO-NH- can be formed when A is a group having an isocyanate group, a group containing -NH-CH2-C(OH)H- can be formed when A is a group having an oxirane group, and a group containing -NH-CH2-CH2- can be formed when A is a group having a vinyl group.
[0014] [3] The absorbent or desorbent according to [1] or [2], wherein n is 4 or 5, and 4 or more of R are halogen atoms.
[0015] The reaction product of the polyallylamine and the compound represented by the general formula (1) in which four or more of R are halogen atoms has an even greater carbon dioxide absorption capacity.
[0016] [4] The absorbent or desorbent according to any one of [1] to [3], wherein the reactant comprises a repeating unit in which the compound represented by formula (1) is bonded to the amino group and a 3-aminopropylene repeating unit, and the number of repeating units in which the compound represented by formula (1) is bonded to the amino group is 5 to 65% based on the total number of repeating units.
[0017] Such a reactant has a significantly excellent carbon dioxide absorption capacity. [Effects of the Invention]
[0018] According to the present invention, it is possible to provide a carbon dioxide absorbent or desorbent having a sufficiently high carbon dioxide absorption capacity. [Brief explanation of the drawings]
[0019] [Figure 1] 1 is an example of a 1H NMR spectrum of a reaction product of polyallylamine and a compound represented by general formula (1). [Figure 2] The adsorption and desorption isotherms of the reactants are shown in Figure 1. (a) is the adsorption and desorption isotherm of reactant PAA-BA15, (b) is the adsorption and desorption isotherm of reactant PAA-BA20, (c) is the adsorption and desorption isotherm of reactant PAA-BA25, (d) is the adsorption and desorption isotherm of reactant PAA-BA30, (e) is the adsorption and desorption isotherm of reactant PAA-BA40, and (f) is the adsorption and desorption isotherm of reactant PAA-BA60. [Figure 3] 1 is a graph showing the carbon dioxide absorption capacity of a reaction product of polyallylamine and benzoic acid. [Figure 4] Adsorption and desorption isotherms of the reactants and polyallylamine. (a) is the adsorption and desorption isotherm of the reactant PAA-FBA. (b) is the adsorption and desorption isotherm of the reactant PAA-HBA. (c) is the adsorption and desorption isotherm of the reactant PAA-TFBA. (d) is the adsorption and desorption isotherm of the reactant PAA-PFBA. (e) is the adsorption and desorption isotherm of the reactant PAA-TFHBA. (f) is the adsorption and desorption isotherm of the control polyamine. [Figure 5] 1 is a graph showing the carbon dioxide absorption capacity of reaction products of a control polyamine with various compounds represented by general formula (1). DETAILED DESCRIPTION OF THE INVENTION
[0020] Hereinafter, embodiments of the present disclosure will be described in detail.
[0021] The carbon dioxide absorbent or desorbent according to this embodiment comprises a reaction product of polyallylamine and a compound represented by the above general formula (1), which bonds to at least one of the amino groups in the 3-aminopropylene repeating units constituting the polyallylamine. In general formula (1), n is a number from 0 to 5, A is a group that bonds to the amino group, and R each independently represents a halogen atom, a hydroxyl group, or a hydrocarbon group. When two or more hydrocarbon groups are present as R, they may be joined together to form a condensed aromatic ring.
[0022] In this specification, polyallylamine refers to a homopolymer of allylamine (3-amino-1-propene) and is composed of 3-aminopropylene repeating units. Polyallylamine may be produced by a known method, or a commercially available product may be used.
[0023] The weight-average molecular weight (Mw) of the polyallylamine may be, for example, 500 to 100,000 or 1,000 to 15,000. The weight-average molecular weight of the polyallylamine is determined by gel permeation chromatography (GPC) using a Hitachi high-performance liquid chromatograph. Specifically, the eluent flow pump is a Hitachi L-2130 inert pump, the detector is a Hitachi Chromaster® 5450, and the columns are a dual-connected Asahi Pack aqueous gel filtration type GS-220HQ (molecular weight exclusion limit: 3,000) and GS-620HQ (molecular weight exclusion limit: 2,000,000). The sample is adjusted to a concentration of 0.5 g / 100 mL with the eluent, and 20 μL of the sample is used. The eluent is a 0.4 mol / L aqueous sodium chloride solution. The column temperature is 30°C, and the flow rate is 1.0 mL / min. A calibration curve was prepared using polyethylene glycols with molecular weights of 106, 194, 420, 615, 1010, 1970, 3930, 7920, 12140, 18380, 21300, 25240, 50630, 77360, 116300, 199800, 278000, 454000, and 895500 as standard samples, and the weight-average molecular weight (Mw) of the copolymer was determined based on the calibration curve. The ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) (Mw / Mn) was approximately 1.0 to 15.0.
[0024] Examples of the halogen atom represented by R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred. When a halogen atom is present as R, the carbon dioxide adsorption capacity becomes larger, and this tendency is more pronounced when the halogen atom is a fluorine atom. When multiple halogen atoms are present as R, the carbon dioxide adsorption capacity becomes larger, and the greater the number of halogen atoms, the more pronounced this tendency becomes. Specifically, it is preferred that three or more halogen atoms are present as R, more preferably four or more halogen atoms, and even more preferably five or more halogen atoms.
[0025] Examples of the hydrocarbon group represented by R include a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkenyl group having 2 to 6 carbon atoms. The linear or branched alkyl group having 1 to 6 carbon atoms may be a linear alkyl group having 1 to 3 carbon atoms, or may be a methyl group. The linear or branched alkenyl group having 2 to 6 carbon atoms may be a linear alkenyl group having 2 or 3 carbon atoms. Examples of fused aromatic rings formed by combining multiple R include a naphthalene ring, an anthracene ring, and a fluorene ring, and the hydrogen atoms of these rings may be substituted with, for example, a hydrocarbon group having 1 to 6 carbon atoms.
[0026] Examples of the group remaining after removing A from the compound represented by general formula (1) include fluorophenyl groups such as phenyl group, monofluorophenyl groups such as 4-fluorophenyl group, difluorophenyl groups such as 3,5-difluorophenyl group, trifluorophenyl groups such as 2,4,6-trifluorophenyl group, tetrafluorophenyl groups such as 2,3,5,6-tetrafluorophenyl group, and pentafluorophenyl group; fluorohydroxyphenyl groups such as tetrafluorohydroxyphenyl groups such as 2,3,5,6-tetrafluoro-4-hydroxyphenyl group; and hydroxyphenyl groups such as monohydroxyphenyl groups such as 4-hydroxyphenyl group. From the viewpoint of further improving the carbon dioxide adsorption capacity, a fluorophenyl group, a fluorohydroxyphenyl group, or a hydroxyphenyl group is preferred, a tetrafluorophenyl group, a pentafluorophenyl group, or a tetrafluorohydroxyphenyl group is more preferred, a tetrafluorophenyl group or a pentafluorophenyl group is even more preferred, and a pentafluorophenyl group is particularly preferred.
[0027] The group A, which bonds to the amino group of polyallylamine, can be a group represented by the following general formula (2). 11 represents a divalent organic group or a single bond, and * represents a bond to the benzene ring in general formula (1).
[0028] [ka]
[0029] In the general formula (2), Z may be a carboxy group, an acyl halide group (—C(═O)X, where X is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an isocyanate group, an oxirane group, or a vinyl group.
[0030] When Z is a carboxyl group or an acyl halide group, the carboxyl group or the acyl halide group can bond with an amino group of the 3-aminopropylene repeating unit constituting the polyallylamine to form -NH-CO-. In this case, the carbon dioxide absorption or desorption agent according to this embodiment can have better thermal stability.
[0031] When Z is an isocyanate group, the isocyanate group can bond with an amino group of a 3-aminopropylene repeating unit constituting the polyallylamine to form --NH--CO--NH--.
[0032] When Z is an oxirane group, the oxirane group can bond with the amino group of the 3-aminopropylene repeating unit that constitutes the polyallylamine to form -NH-CH2-C(OH)H-.
[0033] When Z is a vinyl group, the vinyl group can bond with the amino group of the 3-aminopropylene repeating unit that constitutes the polyallylamine to form -NH-CH2-CH2-.
[0034] In general formula (2), R 11 Examples of R include a single bond, a linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms, or a linear or branched divalent unsaturated hydrocarbon group having 2 to 6 carbon atoms. The linear or branched divalent saturated hydrocarbon group having 1 to 6 carbon atoms may be a linear divalent saturated hydrocarbon group having 1 to 3 carbon atoms, or may be a methylene group. The linear or branched divalent unsaturated hydrocarbon group having 2 to 6 carbon atoms may be a linear divalent unsaturated hydrocarbon group having 2 or 3 carbon atoms. 11 may be a single bond.
[0035] When the carbon dioxide absorption or desorption agent according to this embodiment is composed of a reaction product of polyallylamine and a plurality of compounds represented by general formula (1), the plurality of compounds represented by general formula (1) may be the same or different from one another, and it is preferable that they are the same from one another.
[0036] The reaction product of polyallylamine and the compound represented by general formula (1) preferably comprises a repeating unit in which the compound represented by general formula (1) is bonded to the amino group and a 3-aminopropylene repeating unit.
[0037] From the viewpoint of further improving the carbon dioxide absorption capacity, the number of repeating units in which the compound represented by general formula (1) is bonded to the amino group is preferably 5 to 65%, more preferably 10 to 50%, and even more preferably 15 to 30%, based on the total number of repeating units. Hereinafter, the ratio of the number of repeating units in which the compound represented by general formula (1) is bonded to the amino group based on the total number of repeating units may be referred to as the "introduction rate of the compound represented by general formula (1) into the polyallylamine" or simply as the "introduction rate."
[0038] The introduction rate of the compound represented by general formula (1) into the polyallylamine in the reaction product was measured by proton nuclear magnetic resonance ( 1 The ratio may be determined by HNMR spectroscopy, and in this case, the following procedure can be employed, for example. First, the reaction product is subjected to proton nuclear magnetic resonance spectroscopy using dimethyl sulfoxide-d6 as the measurement solvent, tetramethylsilane as the internal standard, and a frequency of 400 MHz to obtain a proton nuclear magnetic resonance spectrum. An example of the resulting proton nuclear magnetic resonance spectrum is shown in Figure 1. Next, from the proton nuclear magnetic resonance spectrum, the peak area of the hydrogen atom (d in Figure 1) bonded to the amine to which the compound represented by general formula (1) is bonded, and the sum of the peak areas of the hydrogen atoms corresponding to a, b, a', b', and d' shown in the example of Figure 1 are determined. The introduction rate is then calculated using the following formula (A): x: (5-2x) = (peak area of hydrogen atom d): (sum of peak areas of hydrogen atoms a, b, a', b', and d')...(A)
[0039] The carbon dioxide absorbent or desorbent according to this embodiment may be a reaction product of polyallylamine, a compound represented by general formula (1), and another compound that bonds with the amino group in the polyallylamine. 21 A is the same as A in general formula (1). R 21 is an organic group, including hydrocarbon groups. 21 Examples of the hydrocarbon group include a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkenyl group having 2 to 6 carbon atoms. The linear or branched alkyl group having 1 to 6 carbon atoms may be a linear alkyl group having 1 to 3 carbon atoms, or may be a methyl group. The linear or branched alkenyl group having 2 to 6 carbon atoms may be a linear alkenyl group having 2 or 3 carbon atoms. Examples of organic groups other than hydrocarbon groups include groups having a quinone skeleton (for example, groups having an anthraquinone skeleton).
[0040] The number of repeating units in which the other compounds are bonded to the amino groups may be 0 to 10% based on the total number of repeating units.
[0041] The carbon dioxide absorbent or desorbent according to this embodiment has a sufficiently large carbon dioxide absorption capacity. Here, "sufficiently large carbon dioxide absorption capacity" means that the carbon dioxide absorption capacity, determined by evaluating the carbon dioxide absorption capacity of the carbon dioxide absorbent or desorbent, is greater than that of a polyallylamine (sometimes referred to as a "control polyamine") having the same number of repeating units as the reactant for the carbon dioxide absorbent or desorbent. For example, a carbon dioxide absorption capacity that is 10% (1.1 times) or more greater than that of the control polyamine can be said to be sufficiently large. The carbon dioxide absorbent or desorbent according to this embodiment preferably exhibits a carbon dioxide absorption capacity that is 1.2 times or more, 1.5 times or more, 2 times or more, or 3 times or more greater than that of the control polyamine. This absorption capacity may be 1.5 to 30 times, 2 to 20 times, or 3 to 17 times.
[0042] In evaluating the carbon dioxide absorption capacity, the carbon dioxide absorption capacity is determined by subtracting the amount of water contained in the carbon dioxide absorption or desorption agent from the amount of carbon dioxide absorbed when the equilibrium pressure of carbon dioxide in the adsorption / desorption isotherm of the carbon dioxide absorption or desorption agent at 25°C is equal to the saturated vapor pressure. The adsorption / desorption isotherm may be determined specifically by a method described in the Examples. The amount of water may be determined by measuring the mass loss when the carbon dioxide absorption or desorption agent used in measuring the adsorption / desorption isotherm is heated to 100°C in a nitrogen atmosphere. The amount of water may be determined specifically by a method described in the Examples.
[0043] The carbon dioxide absorption or desorption agent according to this embodiment can efficiently absorb carbon dioxide, for example, at 0 to 50° C. The carbon dioxide adsorbed by the agent can be desorbed by heating to, for example, 50 to 400° C. Such absorption and desorption of carbon dioxide can be repeated.
[0044] The compound represented by general formula (1) may be produced by a known method, or a commercially available product may be used.
[0045] A reaction product of polyallylamine and a compound represented by general formula (1) can be obtained by bonding an amino group in the polyallylamine with A of the compound represented by general formula (1). The bonding method can be appropriately set depending on n, R, and A of the compound represented by general formula (1) and the desired introduction rate of the compound represented by general formula (1) into the polyallylamine.
[0046] The reaction product may be obtained, for example, by reacting polyallylamine with the compound represented by general formula (1) in a solvent. During the reaction, a catalyst may be used, and the solvent may be stirred.
[0047] The solvent is not particularly limited as long as it can dissolve polyallylamine and the compound represented by general formula (1) and has low reactivity with the compound represented by general formula (1). Examples of the solvent include water, N,N-dimethylformamide, N,N-dimethylacetamide, methanol, ethanol, acetone, dichloromethane, chloroform, and a mixture of two or more of these.
[0048] The content of polyallylamine in the solvent may be, for example, 0.5 to 20% by mass, or 1 to 10% by mass.
[0049] The content of the compound represented by general formula (1) in the solvent may be, for example, 0.0001 to 10 chemical equivalents relative to the amino groups of the polyallylamine, or 0.005 to 4 chemical equivalents. When the chemical equivalent of the compound represented by general formula (1) relative to the amino groups of the polyallylamine is high, the introduction rate of the compound represented by general formula (1) into the polyallylamine tends to be high.
[0050] The content of the compound represented by general formula (1) in the solvent relative to the amino groups of the polyallylamine may be 0.05 to 2 chemical equivalents when the compound is benzoic acid, 0.9 to 3.8 chemical equivalents when the compound is 4-fluorobenzoic acid, 0.5 to 2.0 chemical equivalents when the compound is 4-hydroxybenzoic acid, 0.005 to 0.02 chemical equivalents when the compound is 2,3,5,6-tetrafluoro-4-hydroxybenzoic acid, 0.005 to 0.02 chemical equivalents when the compound is 2,3,5,6-tetrafluorobenzoic acid, or 0.005 to 0.02 chemical equivalents when the compound is pentafluorobenzoic acid.
[0051] If necessary, other components may be added to the solvent, which may be selected depending on the type of A in the compound represented by general formula (1).
[0052] When A of the compound represented by general formula (1) contains a carboxy group, examples of other components include condensing agents such as 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM), dicyclohexylcarbodiimide (DCC), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), etc. The content of the condensing agent in the solvent may be, for example, 0.05 to 5 chemical equivalents or 0.5 to 1.5 chemical equivalents relative to the compound represented by general formula (1).
[0053] When A in the compound represented by general formula (1) contains an acyl halide group, the other component may be, for example, a base such as triethylamine, which can be used to neutralize the by-product hydrogen halide.
[0054] When A in the compound represented by general formula (1) contains an oxirane group, the other component may be, for example, a base such as triethylamine, which can be used to catalyze the reaction between the oxirane group and the amino group.
[0055] When A in the compound represented by general formula (1) contains a vinyl group, the other component may be, for example, a base such as triethylamine, which can be used to catalyze the reaction between the vinyl group and the amino group (Michael addition, etc.).
[0056] The reaction temperature for the above reaction may be 0 to 100°C or 75 to 95°C, and the reaction time may be 30 minutes to 75 hours or 10 to 25 hours. When the reaction temperature is high, the introduction rate of the compound represented by general formula (1) into the polyallylamine tends to be high. When the reaction time is long, the introduction rate of the compound represented by general formula (1) into the polyallylamine tends to be high.
[0057] After the reaction, the reaction product of polyallylamine and the compound represented by general formula (1) may be precipitated. Precipitation may be performed using acetone. After precipitation, the reaction product may be collected by membrane filtration or the like, washed, and dried. Washing may be performed with acetone and acetonitrile. Drying may be performed by leaving the reaction product in a desiccator at 80 to 95°C for 5 to 15 hours.
[0058] Specifically, the reaction product of polyallylamine and the compound represented by general formula (1) may be produced by the method described in the Examples. [Example]
[0059] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.
[0060] The compound represented by the general formula (1) was synthesized by the method described in the synthesis example below. The incorporation rate of the compound into polyallylamine was measured by proton nuclear magnetic resonance ( 1 1H NMR spectrum, and was calculated as follows.
[0061] (Incorporation rate of compound represented by general formula (1) into polyallylamine) As shown in the example in Figure 1, the introduction rate is determined by the ratio of hydrogen atoms bonded to carbon atoms (a, b, a', and b' in Figure 1) and hydrogen atoms bonded to nitrogen atoms (d and d' in Figure 1) derived from polyallylamine (PAA). 1 It was calculated from the peak area of the HNMR spectrum according to the above formula A.
[0062] 1 H NMR spectra were measured using a 400 JJYH spectrometer (400 MHz, JEOL). Dimethyl sulfoxide-d6 was used as the measurement solvent, and tetramethylsilane was used as the internal standard.
[0063] (Synthesis Example 1: Reaction product of polyallylamine and benzoic acid) Benzoic acid (BA, Tokyo Chemical Industry Co., Ltd.) was dissolved in 10 mL of N,N-dimethylformamide (DMF, anhydrous, Kishida Chemical Co., Ltd.) in an amount of 0.1 chemical equivalent relative to the amino groups of the polyallylamine described below. To this was added 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM, Tokyo Chemical Industry Co., Ltd.) in an amount of 1 chemical equivalent relative to the benzoic acid, and 5 mL of a 15% by weight aqueous solution of polyallylamine (weight average molecular weight 1600, Nittobo Medical Co., Ltd.). The mixture was stirred at 85 °C for 19 hours. Then, 200 mL of acetone (Fujifilm Wako Pure Chemical Industries, Ltd.) was added, and the precipitate was collected by membrane filtration. The precipitate was washed with acetone (Fujifilm Wako Pure Chemical Industries, Ltd.) and acetonitrile (Kanto Chemical Co., Ltd.), and dried overnight in a desiccator at 90° C. to obtain a reaction product of polyallylamine and benzoic acid (reaction product PAA-BA15).
[0064] Reaction products of polyallylamine and benzoic acid (reaction products PAA-BA20, PAA-BA25, PAA-BA30, PAA-BA40, and PAA-BA60) were obtained in the same manner as for obtaining reaction product PAA-BA15, except that the reaction temperature was 85°C, the reaction time was 19 hours, and the reaction temperature, reaction time, and chemical equivalent of benzoic acid relative to the amino group of polyallylamine shown in Table 1 were used instead of 0.1 chemical equivalent of benzoic acid relative to the amino group of polyallylamine.
[0065] [Table 1]
[0066] (Synthesis Example 2: Reaction product of polyallylamine and 4-fluorobenzoic acid) The reaction mixture was 85°C, the reaction time was 19 hours, and 1.85 chemical equivalents of 4-fluorobenzoic acid (FBA, Tokyo Chemical Industry Co., Ltd.) were used instead of 0.1 chemical equivalents of benzoic acid relative to the amino groups of polyallylamine, as shown in Table 2. The reaction mixture was similar to the method for obtaining reaction product PAA-BA15, except that the reaction temperature was 80°C, the reaction time was 19 hours, and 1.85 chemical equivalents of 4-fluorobenzoic acid (FBA, Tokyo Chemical Industry Co., Ltd.) relative to the amino groups of polyallylamine were used instead. 0.674 g of the reaction product (reaction product PAA-FBA) was obtained in a yield of 88.3% by mass.
[0067] (Synthesis Example 3: Reaction product of polyallylamine and 4-hydroxybenzoic acid) The reaction mixture was 85°C, the reaction time was 19 hours, and 1.0 chemical equivalent of 4-hydroxybenzoic acid (HBA, Tokyo Chemical Industry Co., Ltd.) was used instead of 0.1 chemical equivalent of benzoic acid relative to the amino groups of polyallylamine, as shown in Table 2. The reaction mixture was similar to the method for obtaining reaction product PAA-BA15, except that the reaction temperature was 80°C, the reaction time was 19 hours, and 1.0 chemical equivalent of 4-hydroxybenzoic acid (HBA, Tokyo Chemical Industry Co., Ltd.) was used instead. The yield was 84.6% by mass.
[0068] (Synthesis Example 4: Reaction product of polyallylamine and 2,3,5,6-tetrafluoro-4-hydroxybenzoic acid) The reaction mixture was 85°C, the reaction time was 19 hours, and 0.01 chemical equivalents of 2,3,5,6-tetrafluoro-4-hydroxybenzoic acid (TFHBA, Tokyo Chemical Industry Co., Ltd.) were used instead of 0.1 chemical equivalents of benzoic acid relative to the amino groups of polyallylamine, as shown in Table 2. The reaction mixture was similar to the method for obtaining reaction product PAA-BA15, except that the reaction temperature was 85°C, the reaction time was 19 hours, and 0.01 chemical equivalents of 2,3,5,6-tetrafluoro-4-hydroxybenzoic acid relative to the amino groups of polyallylamine were used instead. 0.655 g of reaction product (reaction product PAA-TFHBA) was obtained in a yield of 85.1% by mass.
[0069] (Synthesis Example 5: Reaction product of polyallylamine and 2,3,5,6-tetrafluorobenzoic acid) The reaction mixture was prepared in the same manner as in the preparation of reaction product PAA-BA15, except that the reaction temperature was 90°C, the reaction time was 15 hours, and 0.01 chemical equivalents of 2,3,5,6-tetrafluorobenzoic acid (TFBA, Tokyo Chemical Industry Co., Ltd.) were used instead of 0.1 chemical equivalents of benzoic acid relative to the amino groups of polyallylamine, as shown in Table 2. 0.506 g of a reaction product of polyallylamine and 2,3,5,6-tetrafluorobenzoic acid (reaction product PAA-TFBA) was obtained in a yield of 65.8% by mass.
[0070] (Synthesis Example 6: Reaction product of polyallylamine and pentafluorobenzoic acid) The reaction mixture was 85°C, the reaction time was 19 hours, and 0.01 chemical equivalents of pentafluorobenzoic acid (PFBA, Tokyo Chemical Industry Co., Ltd.) were used instead of 0.1 chemical equivalents of benzoic acid relative to the amino groups of polyallylamine, as shown in Table 2. The reaction mixture was similar to the method for obtaining the reaction product PAA-BA15, except that the reaction temperature was 90°C, the reaction time was 19 hours, and 0.01 chemical equivalents of pentafluorobenzoic acid (PFBA, Tokyo Chemical Industry Co., Ltd.) were used instead. 0.505 g of the reaction product of polyallylamine and pentafluorobenzoic acid (reaction product PAA-PFBA) was obtained in a yield of 65.6% by mass.
[0071] [Table 2]
[0072] (Evaluation of carbon dioxide adsorption / desorption isotherms) The carbon dioxide adsorption / desorption isotherms of each synthesized reactant were determined using a BELSORP-max II (MicrotracBEL). More specifically, each reactant was dried at 100°C for 1.7 hours under reduced pressure and then subjected to the BELSORP-max II. The adsorption isotherms were obtained at 25°C. Figure 2 shows the adsorption / desorption isotherms of the reactants: (a) is the adsorption / desorption isotherm of the reactant PAA-BA15; (b) is the adsorption / desorption isotherm of the reactant PAA-BA20; (c) is the adsorption / desorption isotherm of the reactant PAA-BA25; (d) is the adsorption / desorption isotherm of the reactant PAA-BA30; (e) is the adsorption / desorption isotherm of the reactant PAA-BA40; and (f) is the adsorption / desorption isotherm of the reactant PAA-BA60. FIG. 4 shows the adsorption / desorption isotherms of the reactant and the control polyamine PAA (weight average molecular weight 1600, Nittobo Medical Co., Ltd.), where (a) is the adsorption / desorption isotherm of the reactant PAA-FBA, (b) is the adsorption / desorption isotherm of the reactant PAA-HBA, (c) is the adsorption / desorption isotherm of the reactant PAA-TFBA, (d) is the adsorption / desorption isotherm of the reactant PAA-PFBA, (e) is the adsorption / desorption isotherm of the reactant PAA-TFHBA, and (f) is the adsorption / desorption isotherm of PAA.
[0073] As shown in Figures 2 and 4, the reactants PAA-BA15 to PAA-BA60 and the reactants PAA-FBA, PAA-HBA, PAA-TFHBA, PAA-TFBA, and PAA-PFBA were all capable of adsorbing and desorbing carbon dioxide.
[0074] (Evaluation of carbon dioxide absorption capacity) The carbon dioxide absorption capacity of each synthesized reactant and PAA was determined by subtracting the amount of water contained in the reactant from the amount of carbon dioxide absorbed when the equilibrium pressure of carbon dioxide was equal to the saturated vapor pressure in the "Evaluation of Carbon Dioxide Adsorption / Desorption Isotherms" section above. The water content was measured by subjecting each reactant and PAA used in the evaluation of the adsorption / desorption isotherms to thermogravimetric analysis using a TG8120 (Rigaku Corporation). In this thermogravimetric analysis, the temperature was raised from 25°C at a rate of 4°C / min under a nitrogen atmosphere, and the mass loss of each reactant and PAA was measured until the temperature reached 400°C, and this was used as the water content. The carbon dioxide absorption capacities of the reactants PAA-BA15 to PAA-BA60 are shown in Figure 3. The carbon dioxide absorption capacities of the reactants PAA-BA20, PAA-FBA, PAA-HBA, PAA-TFHBA, PAA-TFBA, PAA-PFBA, and PAA are shown in Figure 5. In FIG. 5, "PAA-BA" means the reactant PAA-BA20, and "PAA (0%)" means PAA.
[0075] As shown in Figure 3, the carbon dioxide absorption capacity of the reaction product of polyallylamine and benzoic acid was greatest when the incorporation rate of benzoic acid into polyallylamine was 20 mol%. Furthermore, as shown in Figure 5, the carbon dioxide absorption capacities of the reaction products, in descending order, were PAA-PFBA, PAA-TFBA, PAA-TFHBA, PAA-FBA, PAA-HBA, and PAA-BA20. Furthermore, the carbon dioxide absorption capacities of these reaction products were 17, 14, 10, 9, 9, and 8 times greater than that of PAA, respectively, demonstrating that they were sufficiently large.
Claims
1. A carbon dioxide absorption or desorption agent comprising a reaction product of polyallylamine and a compound represented by the following general formula (1), which is bonded to at least one amino group of a 3-aminopropylene repeating unit constituting the polyallylamine: 【Chemical Formula 1】 [wherein n is a number from 0 to 5, A is a group bonding to the amino group, and R each independently represents a halogen atom, a hydroxyl group, or a hydrocarbon group, When two or more hydrocarbon groups are present as R, they may be joined together to form a condensed aromatic ring.
2. The bond between the polyallylamine and the compound represented by the general formula (1) provides -NH-CO-, -NH-CO-NH-, -NH-CH ２ -C(OH)H- and -NH-CH ２ -CH ２ 2. The absorbent or desorbent according to claim 1, wherein at least one group selected from the group consisting of - is formed.
3. 2. The absorbent or desorbent according to claim 1, wherein n is 4 or 5, and at least four of R are halogen atoms.
4. the reactant comprises a repeating unit in which the compound represented by formula (1) is bonded to the amino group and a 3-aminopropylene repeating unit, The absorbent or desorbent according to any one of claims 1 to 3, wherein the number of repeating units in which the compound represented by formula (1) is bonded to the amino group is 5 to 65% based on the total number of repeating units.
Citation Information
Patent Citations
Gas adsorption method with aminomethylated bead polymer
JP2002052340A