JP2014034475A - Method for producing activated carbon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide activated carbon with which an electric double-layer capacitor having a high electrostatic capacitance can be produced.SOLUTION: The method for producing activated carbon includes following first to fourth steps: the first step of obtaining a mixture by mixing a block copolymer (z) including a hydrophilic block (S) containing a structural unit derived from an aromatic vinyl compound and having a sulfo group, and a hydrophobic block (T) containing a structural unit derived from an unsaturated hydrocarbon compound and being amorphous, phenols, formaldehyde, and a solvent; the second step of obtaining a solid substance by removing the solvent from the obtained mixture; the third step of obtaining porous carbon by heating the obtained solid substance; and the fourth step of obtaining activated carbon by activating the obtained porous carbon.

Description

  The present invention relates to a method for producing activated carbon.

  Electric double layer capacitors are used for various power sources because of their high storage efficiency. The performance of the electric double layer capacitor is determined by the capacitance. This capacitance can be increased, for example, by increasing the specific surface area of activated carbon used for the electrode material of the electric double layer capacitor.

  As a method for producing porous carbon having a large specific surface area, for example, (1) an organic substance is injected into a template (for example, mesoporous silica or zeolite having regularly formed pores), and (2) the organic substance is carbonized by heating. Then, (3) a manufacturing method including removing the mold is known (Non-patent Document 1, Patent Document 1). By activating these porous carbons, production of activated carbon having a large specific surface area can be expected. However, this method requires mesoporous silica or zeolite having regularly formed pores, and it takes time to produce such mesoporous silica and zeolite. Further, it is necessary to use hydrofluoric acid or a strong alkaline aqueous solution for removing the template, and the waste liquid treatment becomes a problem.

  On the other hand, using a micelle formed by dispersing a surfactant in water as a template, a polymer-micelle complex is formed, and then the complex is heated and carbonized to produce porous carbon. A method is known (Non-Patent Document 2). In this method, since mesoporous silica and zeolite are not used as a template, there is no problem of production of mesoporous silica or the like, use of hydrofluoric acid or the like for removing the template, and subsequent drainage treatment. Further, it is known that when activated carbon obtained by activating porous carbon obtained by this method is used as an electrode material of an electric double layer capacitor, the capacitance is improved (Non-patent Document 3). . However, in the field of electric double layer capacitors, it is required to further increase the capacitance.

JP 2003-206112 A

Journal of Physical Chemistry B (J. Phys. Chem. B), p. 7743 (1999) Chemical Communications (Chem. Comm.), 2125 (2005) Carbon, 1985 (2010)

  An object of this invention is to provide the activated carbon which can manufacture an electrical double layer capacitor with a high electrostatic capacitance.

  As a result of intensive studies by the present inventors to achieve the above object, porous carbon is produced from a mixture obtained by mixing a specific block copolymer, phenols, formaldehyde and a solvent, and the porous carbon It has been found that an electric double layer capacitor having a high capacitance can be obtained from activated carbon produced by activating. The present invention based on this finding is as follows.

[1] A method for producing activated carbon comprising the following first to fourth steps:
Hydrophobic block (T) containing a structural unit derived from an aromatic vinyl compound and having a sulfo group and a structural block derived from an unsaturated hydrocarbon compound and being amorphous A block copolymer (Z) having
Phenols,
With formaldehyde,
A first step of mixing with a solvent to obtain a mixture;
A second step of removing the solvent from the resulting mixture to obtain a solid;
A third step of heating the obtained solid to obtain porous carbon; and a fourth step of activating the obtained porous carbon to obtain activated carbon.
[2] The method for producing activated carbon according to [1], wherein in the third step, the obtained solid is heated at a temperature of 300 to 1200 ° C.
[3] The method for producing activated carbon according to [1] or [2], wherein the fourth step includes the following steps 4-1 to 4-3:
The resulting porous carbon;
An alkali metal hydroxide,
Step 4-1 for obtaining a dispersion by mixing with a solvent;
Step 4-2 for removing the solvent from the obtained dispersion to obtain a solid; and Step 4-3 for obtaining activated carbon by heating the obtained solid at a temperature of 400 to 900 ° C.
[4] Activated carbon obtained by the production method according to any one of [1] to [3].
[5] The activated carbon according to [4], wherein the specific surface area is 1000 m ² / g or more and the total pore volume is 0.3 cm ³ / g or more.

  According to the production method of the present invention, when used as an electrode material of an electric double layer capacitor, activated carbon having an increased capacitance can be produced.

2 is a scanning electron micrograph of porous carbon obtained in Examples 2, 3 and 5. FIG. In the figure, A shows the surface of the porous carbon of Example 2, B shows the surface of the porous carbon of Example 3, C shows the surface of the porous carbon of Example 5, and D shows Example 5. The cross section of the porous carbon of is shown. 2 is a transmission electron micrograph of porous carbon obtained in Examples 2, 3 and 5. FIG. In the figure, A represents the porous carbon of Example 2, B represents the porous carbon of Example 3, and C represents the porous carbon of Example 5.

  The manufacturing method of the present invention includes the first to fourth steps described above. Hereinafter, each process is demonstrated in order.

[First step]
In the first step, a hydrophobic unit containing a structural unit derived from an aromatic vinyl compound and containing a hydrophilic block (S) having a sulfo group and a structural unit derived from an unsaturated hydrocarbon compound, and being amorphous A block copolymer (Z) having a functional block (T);
Phenols,
With formaldehyde,
Mix with solvent to obtain a mixture. Below, a block copolymer (Z) is demonstrated first.

<Block copolymer (Z)>
The block copolymer (Z) has at least one hydrophilic block (S) and one hydrophobic block (T) described below. When the block copolymer (Z) has a plurality of hydrophilic blocks (S), their structures (type of structural unit, degree of polymerization, type of sulfo group, introduction ratio, etc.) may be the same as each other. , May be different. When the block copolymer (Z) has a plurality of hydrophobic blocks (T), their structures (type of structural unit, degree of polymerization, etc.) may be the same or different from each other. .

  As the block copolymer (Z), only one type may be used, or two or more types may be used in combination. Examples of the block copolymer (Z) include an ST type diblock copolymer, an STS type triblock copolymer, a TST type triblock copolymer, and an ST type. S-type triblock copolymer, and a mixture thereof (for example, a mixture of T-S-T type triblock copolymer and S-T type diblock copolymer) and the like (the above-mentioned S and T are Representing a hydrophilic block (S) and a hydrophobic block (T), respectively).

  The weight ratio of the total amount of the hydrophilic block (S) to the total amount of the hydrophobic block (T) is preferably 10:90 to 50:50, and porous carbon with small variation in pore diameter can be obtained with good reproducibility. From the viewpoint, it is more preferably 20:80 to 40:60.

  The ion exchange capacity of the block copolymer (Z) is important in order to obtain porous carbon with a small variation in pore diameter with good reproducibility in the third step described later. In the present invention, the ion exchange capacity of the block copolymer (Z) means an equivalent amount of ion exchange groups per unit mass of the block copolymer (Z). When the block copolymer (Z) has only a sulfo group as an ion exchange group, the ion exchange capacity means the equivalent of the sulfo group per unit mass of the block copolymer (Z). If the ion exchange capacity of the block copolymer (Z) becomes too small, the hydrophilic / hydrophobic difference of each block becomes unclear, and as a result, the specific surface area of the porous carbon decreases. Therefore, the ion exchange capacity is preferably 0.10 meq / g or more, more preferably 0.30 meq / g or more, and particularly preferably 0.75 meq / g or more. On the other hand, if the ion exchange capacity is too large, the hydrophilic / hydrophobic balance of the block copolymer (Z) is lost, and as a result, porous carbon may not be obtained with good reproducibility. Therefore, the ion exchange capacity is preferably 5.00 meq / g or less, more preferably 2.5 meq / g or less, and even more preferably 1.1 meq / g or less. The ion exchange capacity can be calculated using neutralization titration. For example, the ion exchange capacity can be calculated by adding a saturated sodium chloride aqueous solution to the block copolymer (Z) and neutralizing and titrating the generated hydrochloric acid with sodium hydroxide.

The block copolymer (Z) includes, for example, a block copolymer (Z ₀ ) that is the same as the block copolymer except that it does not have a sulfo group [that is, includes a structural unit derived from an aromatic vinyl compound. By sulfonating the block (S ₀ ) and the block copolymer (Z ₀ ) containing a structural unit derived from an unsaturated hydrocarbon compound and having a hydrophobic block (T) that is amorphous Can be manufactured. By this sulfonation, a sulfo group is introduced into an aromatic ring (for example, benzene ring, naphthalene ring, anthracene ring, pyrene ring) in the block (S ₀ ).

The number average molecular weight of the block copolymer (Z ₀ ) measured by a gel permeation chromatography (GPC) method (standard polystyrene conversion) is preferably 5,000 to 200,000, and preferably 30,000 to 150,000. More preferred is 50,000 to 100,000. If the number average molecular weight of the block copolymer (Z ₀ ) is too small or too large, the homogeneity of the pores of the obtained porous carbon tends to decrease.

  An aromatic vinyl compound may use only 1 type and may use 2 or more types together. Examples of the aromatic vinyl compound include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, and 3,5-dimethylstyrene. 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, vinyl biphenyl, vinyl terphenyl, vinyl naphthalene, vinyl anthracene, 4-phenoxy styrene and the like.

  An aromatic vinyl compound having a substituted vinyl group may be used as the aromatic vinyl compound. Examples of the substituent of the vinyl group include an alkyl group having 1 to 4 carbon atoms (for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group). Butyl group), halogenated alkyl groups having 1 to 4 carbon atoms (for example, chloromethyl group, 2-chloroethyl group, 3-chloroethyl group) and aryl groups (for example, phenyl group). Examples of the aromatic vinyl compound having a substituted vinyl group include α-methylstyrene, α-methyl-4-methylstyrene, α-methyl-4-ethylstyrene, 1,1-diphenylethylene, and the like.

  It is desirable that the aromatic vinyl compound does not have a substituent that inhibits sulfonation (for example, an alkyl group having 3 or more carbon atoms) on the aromatic ring.

As an aromatic vinyl compound,
Styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, 2-methoxystyrene, 3- Methoxystyrene, 4-methoxystyrene, vinylbiphenyl, vinylterphenyl, vinylnaphthalene, vinylanthracene, 4-phenoxystyrene, α-methylstyrene, α-methyl-4-methylstyrene, α-methyl-4-ethylstyrene and 1 , 1-diphenylethylene is preferred;
Styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, vinylbiphenyl and α-methylstyrene Is more preferred;
From the viewpoint of sulfonation, styrene, 4-methylstyrene, 4-ethylstyrene, vinylbiphenyl, and α-methylstyrene are more preferable.

The block (S ₀ ) and the hydrophilic block (S) may contain a structural unit derived from one or more monomers other than the aromatic vinyl compound as long as the effects of the present invention are not impaired. Examples of the monomer other than the aromatic vinyl compound include conjugated dienes having 4 to 8 carbon atoms (for example, 1,3-butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 2,4-hexadiene). 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 1,3-heptadiene, etc.), alkenes having 2 to 8 carbon atoms (for example, ethylene, propylene, 1-butene, 2 -Butene, isobutene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, etc.), (meth) acrylic acid esters (for example, (meta ) Methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, etc.), vinyl esters (eg, vinyl acetate, vinyl propionate, vinyl butyrate) Vinyl pivalate, etc.), ethers (e.g., methyl vinyl ether, isobutyl vinyl ether, etc.), and the like. The amount of structural units derived from monomers other than the aromatic vinyl compound is preferably 10% by weight or less in the block (S ₀ ) or hydrophilic block (S), and preferably 5% by weight or less. More preferred.

When the block (S ₀ ) and the hydrophilic block (S) contain two or more structural units, that is, two or more monomers (for example, a combination of two or more aromatic vinyl compounds, or aromatic When copolymerization is performed using a combination of a monomer other than a vinyl compound and an aromatic vinyl compound), the copolymerization form is desirably random.

The number average molecular weight of one block (S ₀ ) measured by gel permeation chromatography (GPC) method (standard polystyrene conversion) is preferably in the range of 1,000 to 50,000, and preferably 3,000 to 40,000. The range of 5,000 to 25,000 is more preferable. When the number average molecular weight is less than 1,000 or exceeds 50,000, the homogeneity of the pores of the obtained porous carbon is lowered, thereby causing the activation efficiency of the porous carbon to be lowered. There is. As a result, when the obtained activated carbon is used as an electric double layer capacitor electrode, sufficient electrostatic capacity may not be obtained.

The hydrophobic block (T) includes a structural unit derived from an unsaturated hydrocarbon compound and is amorphous. Here, that the hydrophobic block (T) in the block copolymer (Z ₀ ) or (Z) is amorphous means that the dynamic viscoelasticity of the block copolymer (Z ₀ ) or (Z) is reduced. It can be confirmed by measurement that there is no change in the storage elastic modulus derived from the crystalline olefin polymer.

  Only one type of unsaturated hydrocarbon compound may be used, or two or more types may be used in combination. The unsaturated hydrocarbon compound is not particularly limited as long as it has a polymerizable carbon-carbon double bond, but a chain unsaturated hydrocarbon compound is preferable. Examples of the chain unsaturated hydrocarbon compound include olefins having 2 to 8 carbon atoms (ethylene, propylene, 1-butene, 2-butene, isobutene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, etc.), conjugated diene compounds having 4 to 8 carbon atoms (1,3-butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 2, 4-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 1,3-heptadiene, etc.). When a conjugated diene compound is polymerized as an unsaturated hydrocarbon compound, the polymerization (bonding) may be a 1,2-bond or a 1,4-bond, or these may be mixed.

As unsaturated hydrocarbon compounds,
Ethylene, propylene, 1-butene, 2-butene, isobutene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, 1,3- Butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 2,4-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 1,3-heptadiene Preferably;
1,3-butadiene, isobutene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 2,4-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 1,3-heptadiene is more preferred;
More preferred are 1,3-butadiene, isobutene, isoprene, 2,3-dimethyl-1,3-butadiene and 2-ethyl-1,3-butadiene.

  The hydrophobic block (T) may contain a structural unit derived from a monomer other than the unsaturated hydrocarbon compound as long as the effects of the present invention are not impaired. Examples of monomers other than unsaturated hydrocarbon compounds include aromatic vinyl compounds such as styrene and vinyl naphthalene, halogen-containing vinyl compounds such as vinyl chloride, vinyl esters (vinyl acetate, vinyl propionate, vinyl butyrate, pivalic acid). Vinyl), vinyl ether (methyl vinyl ether, isobutyl vinyl ether, etc.) and the like. The amount of structural units derived from monomers other than the unsaturated hydrocarbon compound is preferably 5% by weight or less in the hydrophobic block (T).

  When the hydrophobic block (T) includes two or more structural units, that is, two or more monomers (for example, a combination of two or more unsaturated hydrocarbon compounds, or other than unsaturated hydrocarbon compounds) When copolymerization is performed using a combination of a monomer and an unsaturated hydrocarbon compound, the copolymerization form is desirably random.

  If the number average molecular weight of one hydrophobic block (T) is too small or too large, the homogeneity of the pores of the obtained porous carbon tends to be lowered. For this reason, the number average molecular weight of one hydrophobic block (T) measured by gel permeation chromatography (GPC) method (standard polystyrene conversion) is preferably in the range of 3,000 to 150,000, and preferably in the range of 20,000 to The range of 100,000 is more preferable, and the range of 30,000 to 75,000 is more preferable.

The block copolymer (Z ₀ ) used for the sulfonation can be appropriately produced by a radical polymerization method, an anionic polymerization method, a cationic polymerization method, a coordination polymerization method, or the like depending on the type of the structural unit, molecular weight, and the like. . A radical polymerization method, an anionic polymerization method, or a cationic polymerization method is preferable from the viewpoint of industrial ease, and a living radical polymerization method, a living anion polymerization method, and a living cationic polymerization method are more preferable from the viewpoint of molecular weight, molecular weight distribution, and the like.

As a specific example of the production method of the block copolymer (Z ₀ ), the block (S ₀ ) is formed from an aromatic vinyl compound such as styrene, α-methyl styrene, t-butyl styrene, and the hydrophobic block (T) is A method for producing a block copolymer (Z ₀ ) formed from conjugated diene or isobutene will be described. In this case, from the viewpoint of industrial ease, molecular weight, molecular weight distribution, ease of bonding between the block (S ₀ ) and the hydrophobic block (T), the block copolymer (Z ₀ ) is a living anion polymerization method or It is preferable to produce by a living cationic polymerization method.

In order to produce the block copolymer (Z ₀ ) by living anionic polymerization,
(1) An aromatic vinyl compound, a conjugated diene, and an aromatic vinyl compound are sequentially polymerized in a nonpolar solvent such as cyclohexane in the presence of an anionic polymerization initiator at a temperature of 20 to 100 ° C., and S ₀ − Method for obtaining a T-S ₀ type triblock copolymer (Z ₀ ) (wherein S ₀ and T represent a block (S ₀ ) and a hydrophobic block (T), respectively, the same shall apply hereinafter);
(2) A coupling agent such as phenyl benzoate after sequential polymerization of an aromatic vinyl compound and a conjugated diene in the presence of an anionic polymerization initiator in a nonpolar solvent such as cyclohexane at a temperature of 20 to 100 ° C. To obtain a S ₀ -T-S ₀ type triblock copolymer (Z ₀ );
(3) In a nonpolar solvent such as cyclohexane, in the presence of an organic lithium compound as an anionic polymerization initiator and a polar compound (for example, THF, amine, etc.) that is an activator of a polymerization terminal anion, −30 ° C. to 30 ° C. After the aromatic vinyl compound is polymerized at the temperature of the polymer, and the resulting living polymer is polymerized with a conjugated diene, a coupling agent such as phenyl benzoate is added, and S ₀ -T-S ₀ type block copolymer A method for obtaining a coalescence (Z ₀ );
(4) In the presence of an anionic polymerization initiator in a non-polar solvent such as cyclohexane, t-butylstyrene, styrene, and conjugated diene are sequentially added one or more times in the desired order under a temperature condition of 20 to 100 ° C. A method of obtaining a block copolymer (Z ₀ ) comprising three or more types of blocks;
Etc. are adopted.

In order to produce the block copolymer (Z ₀ ) by living cationic polymerization,
(5) Cationic polymerization of isobutene in the presence of Lewis acid using a bifunctional halogenated initiator at -78 ° C in a mixed solvent of halogenated hydrocarbon and hydrocarbon, and then aromatic vinyl such as styrene. A method of polymerizing a compound to obtain a S ₀ -T-S ₀ type triblock copolymer (Z ₀ ) (for example, a method described in Macromol. Chem., Macromol. Symp. 32, 119 (1990).)
Etc. are adopted.

When the unsaturated hydrocarbon compound has a plurality of carbon-carbon double bonds, usually the carbon-carbon double bonds remain in the hydrophobic block (T) after polymerization. In this case, some or all of the remaining carbon-carbon double bonds may be converted to saturated bonds by a known hydrogenation reaction. The hydrogenation rate of the carbon-carbon double bond can be calculated by a commonly used method, for example, ¹ H-NMR measurement. The hydrogenation rate of the carbon-carbon double bond is preferably 50 mol% or more, and more preferably 80 mol% or more.

A block copolymer (Z) can be produced by sulfonating the block copolymer (Z ₀ ) produced as described above. This sulfonation can be performed by a known method. The method of sulfonation, for example, the block copolymer (Z ₀₎ of a solution or a method of adding a sulfonating agent to be described later or a suspension, the block copolymer (Z ₀₎ to a gaseous sulfonating agent The method of adding directly is mentioned.

  Sulfonating agents include: sulfuric acid; a mixture of sulfuric acid and aliphatic acid anhydride; chlorosulfonic acid; a mixture of chlorosulfonic acid and trimethylsilyl chloride; sulfur trioxide; a mixture of sulfur trioxide and triethyl phosphate; An aromatic organic sulfonic acid such as 1,6-trimethylbenzenesulfonic acid;

  Examples of the solvent used for sulfonation include halogenated hydrocarbons such as methylene chloride; linear aliphatic hydrocarbons such as hexane; cyclic aliphatic hydrocarbons such as cyclohexane; and mixed solvents thereof.

<Phenols and formaldehyde>
In the present invention, the phenol means a phenol or a phenol in which a hydrogen atom of a benzene ring is substituted with a substituent (hereinafter referred to as “substituted phenol”). As a substituent of substituted phenol, a hydroxyl group, an alkoxy group, an alkoxycarbonyl group etc. are mentioned, for example, The number of the substituents becomes like this. Preferably it is 1-3, More preferably, it is 1-2. Only 1 type may be used for phenols and it may use 2 or more types together. Examples of phenols include phenol, dihydroxybenzene (that is, 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, 1,4-dihydroxybenzene), and among these, 1,3-dihydroxybenzene (that is, Resorcinol) is preferred.

  Formaldehyde may be mixed as a solution or in the form of a polymer such as paraformaldehyde. Examples of the solvent for the formaldehyde solution include water, a polar organic solvent, and a mixed solvent of water and a polar organic solvent. Examples of the polar organic solvent include alcohols such as methanol, ethanol, n-propanol, 2-propanol and 2-methyl-1-propanol; ethers such as tetrahydrofuran (THF); ketones such as acetone and cyclohexanone; These may be used alone or in combination of two or more. Formaldehyde is preferably mixed as a formaldehyde solution, and more preferably mixed as a formaldehyde aqueous solution. When the aqueous formaldehyde solution is used, the concentration is preferably 5 to 80% by weight, more preferably 10 to 50% by weight, and still more preferably 37 to 50% by weight.

  The molar ratio of phenols: formaldehyde used in the first step is preferably in the range of 1: 0.1 to 1:10, and more preferably in the range of 1: 0.5 to 1: 5. Moreover, the range of 10-500 weight part is preferable with respect to 100 weight part of block copolymers (Z), and, as for the usage-amount of formaldehyde, the range of 30-250 is more preferable.

<Solvent>
As the solvent used in the first step, alcohols such as methanol, ethanol, n-propanol, 2-propanol and 2-methyl-1-propanol; ethers such as tetrahydrofuran (THF); ketones such as acetone and cyclohexanone; polarities such as Organic solvents are preferred. These polar organic solvents may be used alone or in combination of two or more. For the purpose of improving the solubility of the block copolymer (Z), the above polar organic solvent and a nonpolar organic solvent such as toluene may be mixed and used. Moreover, you may mix the said polar organic solvent and water.

From the viewpoint of high solubility of the block copolymer (Z), as a solvent used in the first step,
THF; Mixed solvent of THF and ethanol; Mixed solvent of THF and n-propanol; Mixed solvent of THF and water; Cyclohexanone; Mixed solvent of cyclohexanone and ethanol; Mixed solvent of toluene and 2-propanol; A mixed solvent with 2-methyl-1-propanol;
THF; mixed solvent of THF and ethanol; mixed solvent of THF and n-propanol ;; cyclohexanone; mixed solvent of cyclohexanone and ethanol; mixed solvent of toluene and 2-propanol; toluene and 2-methyl-1-propanol And a mixed solvent with
More preferably, THF; mixed solvent of THF and ethanol; mixed solvent of THF and n-propanol;

  The solid content of the mixture prepared in the first step is preferably 0.5 to 30% by weight, more preferably 1 to 25% by weight. If the solid content is lower than 0.5% by weight, the productivity tends to deteriorate, and conversely if the solid content is higher than 30% by weight, the viscosity of the resulting mixture increases and handling becomes difficult. There is a case. The viscosity of the mixture is preferably 20 Pa · s or less, more preferably 10 Pa · s or less. When the viscosity of the mixture exceeds 20 Pa · s, the handling tends to be difficult.

  In the first step, the temperature at the time of mixing the block copolymer (Z), the phenols, formaldehyde, and the solvent is preferably in the range of 0 to 80 ° C, more preferably in the range of 5 to 50 ° C, The range of 10-30 degreeC is further more preferable. Moreover, from the viewpoint of improving the homogeneity of the pores of the obtained porous carbon, the mixing time is preferably in the range of 1 to 72 hours, and more preferably in the range of 10 to 30 hours.

<Preferred combination>
A preferred combination of block copolymer, phenols, formaldehyde and solvent is as follows:
(I) Block copolymer (Z)
Styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, 2-methoxystyrene, 3- Methoxystyrene, 4-methoxystyrene, vinylbiphenyl, vinylterphenyl, vinylnaphthalene, vinylanthracene, 4-phenoxystyrene, α-methylstyrene, α-methyl-4-methylstyrene, α-methyl-4-ethylstyrene and 1 , A hydrophilic block (S) containing a structural unit derived from an aromatic vinyl compound selected from the group consisting of 1-diphenylethylene and having a sulfo group, and ethylene, propylene, 1-butene, 2-butene, isobutene, 1-pentene, 2-pentene, 1-hexene, 2-he Xene, 1-heptene, 2-heptene, 1-octene, 2-octene, 1,3-butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene, 2,4-hexadiene, 2,3-dimethyl- A hydrophobic block comprising a structural unit derived from an unsaturated hydrocarbon compound selected from the group consisting of 1,3-butadiene, 2-ethyl-1,3-butadiene and 1,3-heptadiene, and is amorphous (T)
A block copolymer (Z).
(Ii) Phenols Phenols selected from the group consisting of phenol and dihydroxybenzene.
(Iii) Formaldehyde Formaldehyde solution.
(Iv) Solvent THF; Mixed solvent of THF and ethanol; Mixed solvent of THF and n-propanol ;; Mixed solvent of THF and water; Cyclohexanone; Mixed solvent of cyclohexanone and ethanol; Toluene and 2-propanol Mixed solvent; or mixed solvent of toluene and 2-methyl-1-propanol.

A more preferred combination of block copolymer, phenols, formaldehyde and solvent is as follows:
(I) Block copolymer (Z)
Styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, vinylbiphenyl and α-methylstyrene A hydrophilic block (S) containing a structural unit derived from an aromatic vinyl compound selected from the group consisting of and having a sulfo group, and 1,3-butadiene, isobutene, 1,3-pentadiene, isoprene, 1,3 Derived from an unsaturated hydrocarbon compound selected from the group consisting of hexadiene, 2,4-hexadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 1,3-heptadiene A block copolymer (Z) having a hydrophobic block (T) containing a structural unit and being amorphous.
(Ii) Phenols Phenols selected from the group consisting of phenol and resorcinol.
(Iii) Formaldehyde An aqueous formaldehyde solution.
(Iv) Solvent THF; Mixed solvent of THF and ethanol; Mixed solvent of THF and n-propanol ;; Cyclohexanone; Mixed solvent of cyclohexanone and ethanol; Mixed solvent of toluene and 2-propanol; Mixed solvent with methyl-1-propanol.

Further preferred combinations of block copolymers, phenols, formaldehyde and solvents are as follows:
(I) Block copolymer (Z)
A hydrophilic block (S) comprising a structural unit derived from an aromatic vinyl compound selected from the group consisting of styrene, 4-methylstyrene, 4-ethylstyrene, vinylbiphenyl and α-methylstyrene, and having a sulfo group, and A structural unit derived from an unsaturated hydrocarbon compound selected from the group consisting of 1,3-butadiene, isobutene, isoprene, 2,3-dimethyl-1,3-butadiene and 2-ethyl-1,3-butadiene. And a block copolymer (Z) having a hydrophobic block (T) which is amorphous.
(Ii) Phenols Resorcinol.
(Iii) Formaldehyde aqueous solution of formalin (ie, an aqueous solution of formaldehyde having a concentration of 37% by weight or more).
(Iv) Solvent THF; Mixed solvent of THF and ethanol; or Mixed solvent of THF and n-propanol.

[Second step]
In the second step, the solvent is removed from the obtained mixture to obtain a solid. Examples of the method for removing the solvent include known methods such as (1) natural drying at room temperature, (2) heating, (3) reduced pressure, or (4) combination of heating and reduced pressure. After the mixture is coated on a substrate such as glass or silicon wafer, the solvent may be removed using the above-described method. As a method for coating the substrate, a known method such as a bar coater, a roll coater, a gravure coater, dip coating, spin coating or spray coating is used. When heating to remove the solvent, the temperature is preferably 30 to 150 ° C, more preferably 60 to 120 ° C. When the pressure is reduced to remove the solvent, the pressure is preferably 0.01 to 100 Torr, more preferably 0.1 to 10 Torr. The time required for the second step is preferably 1 to 100 hours, more preferably 10 to 50 hours. Solvent removal is preferably performed by heating the mixture in an air atmosphere. When the solid is kept at 100 ° C., it is preferable to remove the solvent until the weight reduction rate is 0.1% or less per minute.

  When the solvent of the mixture is removed by heating, the heating in the second step and the third step may be continued. That is, even after the solvent of the mixture is removed by heating, heating may be continued as it is (in some cases, the temperature is further raised) to form porous carbon.

[Third step]
In the third step, the obtained solid is heated to obtain porous carbon. The obtained porous carbon preferably has regularly a large number of pores having a pore diameter of 10 to 50 nm.

  The heating in the third step is preferably performed in an inert gas atmosphere such as nitrogen or argon. The heating temperature is preferably 300 to 1200 ° C, more preferably 400 to 1000 ° C. The heating time is preferably 30 minutes to 12 hours.

[Fourth step]
In the fourth step, the obtained porous carbon is activated to obtain activated carbon. For the activation of the porous carbon, a known method (chemical activation, gas activation) can be used. The chemical activation is generally performed by heating porous carbon infiltrated with chemicals (zinc chloride, phosphoric acid, alkali metal hydroxide, etc.). The gas activation is generally performed by bringing porous carbon into contact with a gas (water vapor, carbon dioxide, air, combustion gas, etc.) at a high temperature (for example, 700 to 1000 ° C.).

As an activation method, chemical activation is preferable, and chemical activation using an alkali metal hydroxide is more preferable. The fourth step of the preferred embodiment includes the following steps 4-1 to 4-3:
The resulting porous carbon;
An alkali metal hydroxide,
Step 4-1 for obtaining a dispersion by mixing with a solvent;
Step 4-2 for removing the solvent from the obtained dispersion to obtain a solid; and Step 4-3 for obtaining activated carbon by heating the obtained solid at a temperature of 400 to 900 ° C.

  Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide and the like. Only 1 type may be used for an alkali metal hydroxide, and 2 or more types may be used together. In order to produce activated carbon that can achieve a large capacitance, sodium hydroxide, potassium hydroxide, or a mixture thereof is preferred, and potassium hydroxide is more preferred.

  If the amount of the alkali metal hydroxide used in the step 4-1 is too small, the properties of the obtained activated carbon may vary. On the other hand, if the amount is too large, not only is it not economical, but when the obtained activated carbon is used as an electrode material for an electric double layer capacitor, the capacitance may decrease. Therefore, the amount of alkali metal hydroxide used is preferably 1 part by weight or more, more preferably 1.5 to 10 parts by weight, and further preferably 2 to 6 parts by weight with respect to 1 part by weight of porous carbon.

  As a solvent (dispersion solvent) used at the 4th process, water is preferred. For example, the porous carbon, the alkali metal hydroxide, and water may be mixed by adding porous carbon to the alkali metal hydroxide aqueous solution and mixing them. The mixing temperature is preferably 30 to 150 ° C., more preferably 60 to 100 ° C., and the mixing time is preferably 1 to 24 hours, more preferably 2 to 10 hours.

  In the step 4-2, the solvent is removed from the obtained dispersion to obtain a solid. Examples of the method for removing the solvent include known methods such as (1) heating, (2) reduced pressure, or (3) a combination thereof. When heating for removing the solvent, the temperature is preferably 30 to 150 ° C, more preferably 50 to 120 ° C. When the pressure is reduced to remove the solvent, the pressure is preferably 0.01 to 100 Torr, more preferably 0.1 to 10 Torr. The time required for the step 4-2 is preferably 1 to 50 hours, more preferably 10 to 35 hours. Solvent removal is preferably performed by heating the dispersion in an air atmosphere.

  When removing the solvent of a dispersion liquid by heating, you may continue heating of the 4-2 process and the 4-3 process. That is, even after removing the solvent of the dispersion by heating, heating may be continued as it is to raise the temperature to form activated carbon.

  In the fourth step, the obtained solid is heated at a temperature of 400 to 900 ° C. (preferably 500 to 850 ° C.) (hereinafter referred to as “activation temperature”) to obtain activated carbon. When activation temperature exceeds 900 degreeC, when the activated carbon obtained is used as an electrode of an electric double layer capacitor, there exists a tendency for an electrostatic capacitance to become small. Moreover, when the activation temperature is less than 400 ° C., the obtained activated carbon may have high electrical resistance.

  In the 4th-3 step, the obtained solid is heated to reach the activation temperature and then cooled quickly, but it is preferable to heat and hold the solid at the activation temperature for a certain period of time. . Therefore, the holding time is preferably in the range of 0.3 to 5 hours, and more preferably in the range of 0.5 to 3 hours. When the holding time is less than 0.3 hours, the specific surface area of the obtained activated carbon becomes small. On the other hand, when the holding time exceeds 5 hours, a graphite structure develops with the obtained activated carbon, which is used for the electric double layer capacitor. When used as an electrode material, the capacitance tends to decrease.

  In order to suppress the combustion of porous carbon, it is preferable to perform the temperature rise, heat holding, and subsequent cooling in the step 4-3, for example, in an inert gas atmosphere such as nitrogen or argon. Heating for activation may be performed either on a fixed bed in which a solid is fixed or on a moving bed accompanied by movement such as rotation and stirring, and may be performed either batchwise or continuously.

  It is preferable to remove the alkali metal hydroxide contained therein from the activated carbon obtained as described above. The removal of the alkali metal hydroxide is generally performed by washing the activated carbon with an acidic aqueous solution and / or water. The time required for washing is usually 30 minutes to 6 hours.

[Activated carbon]
The present invention also provides activated carbon obtained by the above production method. From the viewpoint of increasing the capacitance of the electric double layer capacitor electrode, the specific surface area of the activated carbon of the present invention is preferably 1000 m ² / g or more, and more preferably 1500 m ² / g or more. From the same viewpoint, the total pore volume of the activated carbon of the present invention is preferably 0.3 cm ³ / g or more, and more preferably 0.5 cm ³ / g or more.

  The specific surface areas of porous carbon and activated carbon can be measured by a nitrogen BET adsorption method (Shimazu review 48, No. 1, pages 35-44, 1991). Moreover, the pore volume (micropore volume, mesopore volume, macropore volume, and total pore volume) of porous carbon and activated carbon can be measured by the BJH method from an adsorption curve of a nitrogen adsorption isotherm. Specifically, the specific surface area and the pore volume can be measured as described in Examples described later.

The effect (capacitance improvement) of the activated carbon of the present invention is, for example, constructing a tripolar cell with Ag / Ag ⁺ as a reference electrode, an electrode using activated carbon as a working electrode, and Pt as a counter electrode, This can be confirmed by measuring the capacitance. Specifically, as described in the examples described later, the capacitance can be measured to confirm the effect of the activated carbon of the present invention.

  The activated carbon of the present invention is suitable as an electrode material for electric double layer capacitors. The activated carbon of the present invention may be used by mixing with other carbon materials (for example, known carbon black and activated carbon).

The manufacturing method of an electrode is not specifically limited, The manufacturing method known conventionally can be used. Examples of the method for producing an electrode include the following:
(1) A method in which a dispersion of activated carbon is prepared in advance, an active material, a binder, and various additives are added to the dispersion and further dispersed, applied to a current collector, and then dried.
(2) Activated carbon, active material, binder, various additives are simultaneously dispersed in a solvent, applied to a current collector, and then dried.
(3) A method in which activated carbon, an active material, a binder, and various additives are mixed by a dry mixer, and the resulting mixture is bound to a current collector by pressurization (for example, compression molding).

  As the dispersion solvent, for example, N-methylpyrrolidone (NMP) can be used. The dispersion may be performed using a known disperser or a mixer. Examples of the disperser or the mixer include a disperser used at the time of preparing a paint such as a ball mill, a sand mill, a three-roll, a high-speed disperser, and a dry mixer such as a Henschel mixer and a planetary ball mill.

  In a typical electrode manufacturing method, for example, the activated carbon of the present invention is bound to polyethylene, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), carboxymethylcellulose (CMC), or the like. After adding the agent (binder), the electrode can be produced by pressure roll molding into a sheet shape or a plate shape. At this time, graphite powder, acetylene black or the like may be added as a conductive material. The electrode manufactured in this manner is cut into a desired size and shape, a separator is interposed between both electrodes, inserted into a container, an electrolyte is injected, and the sealing is closed using a sealing plate and a gasket. Thus, a monopolar cell can be formed. Various separators can be used. For example, a polyethylene separator, a nylon nonwoven fabric separator, a polypropylene nonwoven fabric separator, and the like can be suitably used.

  Hereinafter, the present invention will be described in more detail. In addition, this invention is not limited to the Example demonstrated here.

1. Measurement Method (1) Measurement of Number Average Molecular Weight The number average molecular weight of the block copolymer (Z ₀ ) was measured with the following measuring machine and conditions.
GPC system: "HLC-8220GPC" manufactured by Tosoh Corporation
Column: TSKgel Super Multipore HZ-M
TSK guard Column Super MP-M
TSK gel G3000H
RI detector: HLC-8220GPC
Column oven temperature: 40 ° C
Eluent: Tetrahydrofuran Standard sample: Conversion was made using a calibration curve of standard polystyrene.

(2) Measurement of hydrogenation rate and sulfonation rate ¹ H-NMR was measured according to the following measuring machine and conditions, and the hydrogenation rate of the block copolymer (Z ₀ ) and the sulfone of the block copolymer (Z) were measured. The conversion rate was calculated.
NMR system: JEOL JNM-ECX400
Solvent: Deuterated chloroform Reference peak: Tetramethylsilane

(3) Amorphous Evaluation of Hydrophobic Block (T) A 20 wt% toluene / isopropyl alcohol (weight ratio 5/5) solution of the block copolymer (Z) was prepared, and a release-treated PET film (Mitsubishi Resin) "MRV" manufactured by Co., Ltd.) with a thickness of about 350 μm, dried in a hot air dryer at 100 ° C. for 4 minutes, and then peeled off from the release-treated PET film at 25 ° C. Film was obtained. Using the wide-range dynamic viscoelasticity measuring apparatus ("DVE-V4FT Rheospectr" manufactured by Rheology Co., Ltd.) The temperature was raised to 250 ° C., and the storage elastic modulus (E ′), loss elastic modulus (E ″), and loss tangent (tan δ) were measured. The amorphous nature of the hydrophobic block (T) was evaluated from the presence or absence of a change in storage elastic modulus at 80 to 100 ° C. derived from the crystalline olefin polymer. As a result, in all the block copolymers (Z) obtained in the following Examples and Comparative Examples, the storage elastic modulus did not change, and the hydrophobic blocks (T) were amorphous.

(4) Measurement of specific surface area and pore volume Using BELLSORP-miniII, an automatic specific surface area / pore distribution measuring device manufactured by Nippon Bell Co., Ltd., measuring the BET specific surface area by a multipoint method using liquid nitrogen, The specific surface area of the porous carbon or activated carbon was calculated within the range in which the parameter C becomes positive. In addition, the micropore volume (Vmicro), mesopore volume (Vmeso), macropore volume (Vmacro), and total pore volume (Vtotal) of porous carbon or activated carbon are determined by the BJH method from the adsorption curve of the nitrogen adsorption isotherm. Used to calculate. Pretreatment for measurement of specific surface area and pore volume was performed at 100 ° C. for 24 hours. Note that a micropore refers to a hole having a width of 2 nm or less, a mesopore refers to a hole having a width greater than 2 nm and not greater than 50 nm, and a macropore refers to a hole having a width greater than 50 nm.

(5) Measurement of electrostatic capacity Activated carbon, carbon black (manufactured by Tokai Carbon Co., Ltd.) and PTFE powder (manufactured by Dupont-Mitsui Fluorochemicals) of the following examples and comparative examples are mixed at a weight ratio of 8: 1: 1 and pressurized. The molded product was sandwiched between platinum meshes to form a working electrode. Using a tripolar cell with 1 M sulfuric acid as the electrolyte, Ag / Ag ⁺ as the reference electrode, and Pt as the counter electrode, a charge / discharge test was conducted by a constant current method, and a current density of 100 mA / g and Each capacitance of 400 mA / g was measured.

2. Synthesis of Block Copolymer (Z ₀ ) and Block Copolymer (Z) Synthesis Example 1: Synthesis of Block Copolymer (Z ₀ ) α was sufficiently dehydrated after sufficiently substituting the pressure vessel equipped with a stirrer with nitrogen. -172 g of methylstyrene, 258.1 g of cyclohexane, 28.8 g of n-hexane and 5.9 g of tetrahydrofuran were added. Subsequently, 17.5 mL of sec-butyl lithium (1.3 M cyclohexane solution) was added to the polymerization solution, and polymerization was performed at −10 ° C. for 5 hours. When the number average molecular weight of poly (α-methylstyrene) after polymerization for 5 hours was measured by GPC, it was 6,400 in terms of polystyrene. Next, 27 g of 1,3-butadiene was added to the polymerization solution and stirred for 30 minutes at −10 ° C., and then 1,703 g of cyclohexane was added. The number average molecular weight of the obtained polybutadiene block was 3640. Next, 303 g of 1,3-butadiene was added to the polymerization solution, the temperature was raised to 60 ° C., and polymerization was performed for 2 hours. Furthermore, 27.0 mL of α, α′-dichloro-p-xylene (0.3 M toluene solution) was added to the polymerization solution in the pressure vessel, and the mixture was stirred at 60 ° C. for 1 hour to conduct a coupling reaction. An α-methylstyrene) -polybutadiene-poly (α-methylstyrene) type triblock copolymer (hereinafter abbreviated as “mSBmS”) was synthesized. The number average molecular weight of the obtained mSBmS was 74000, the 1,2-bond amount determined from ¹ H-NMR measurement was 43.9%, and the content of α-methylstyrene unit was 28% by weight. Further, it was confirmed by composition analysis by ¹ H-NMR spectrum measurement that α-methylstyrene was not substantially contained in the polybutadiene block.

After charging the obtained mSBmS cyclohexane solution into a pressure vessel sufficiently purged with nitrogen, using a Ni / Al Ziegler-based hydrogenation catalyst, a hydrogenation reaction was performed at 80 ° C. for 5 hours in a hydrogen atmosphere. A poly (α-methylstyrene) -hydrogenated polybutadiene-poly (α-methylstyrene) type triblock copolymer (hereinafter referred to as a block copolymer (Z ₀ -1)) was obtained. The resulting block copolymer hydrogenation rate of _(Z 0 -1) was calculated by ¹ H-NMR spectrum measurement, it was 99.6%.

Synthesis Example 2: Synthesis of Block Copolymer (Z) 100 g of the block copolymer (Z ₀ -1) obtained in Synthesis Example 1 was vacuum-dried in a glass reaction vessel equipped with a stirrer for 1 hour, and then After nitrogen substitution, 1000 mL of methylene chloride was added and dissolved by stirring at 35 ° C. for 2 hours to prepare a methylene chloride solution of the block copolymer (Z ₀ -1). Separately, 21.0 mL of acetic anhydride and 9.34 mL of sulfuric acid were reacted in 41.8 mL of methylene chloride at 0 ° C. to obtain a sulfonating agent. The sulfonating agent was gradually added dropwise over 20 minutes to a methylene chloride solution of the block copolymer (Z ₀ -1). The reaction solution after the dropping was stirred at 35 ° C. for 0.5 hour to perform sulfonation. After sulfonation, the reaction solution was poured into 2 L of distilled water while stirring to precipitate a copolymer. The precipitated copolymer was washed with distilled water at 90 ° C. for 30 minutes and then filtered. This washing and filtration operation is repeated until there is no change in the pH of the washing water, and the finally collected copolymer is vacuum-dried to obtain a sulfonated copolymer (hereinafter referred to as block copolymer (Z-1)). Obtained). The resulting block copolymer (Z-1) had a sulfonation rate of 27 mol% and an ion exchange capacity of 0.8 meq / g.

Synthesis Example 3: Synthesis of Block Copolymer (Z) A block copolymer (Z ₀ − was synthesized in the same manner as in Synthesis Example 2 except that the reaction temperature for sulfonation was changed to 25 ° C. and the reaction time was changed to 7 hours. The sulfonation of 1) was performed. The resulting sulfonated copolymer (hereinafter referred to as block copolymer (Z-2)) had a sulfonation rate of 50 mol% and an ion exchange capacity of 1.06 meq / g.

3. Production and evaluation of activated carbon Example 1
First, porous carbon was produced as follows. Specifically, 9.0 mL of THF was added to a 30 mL wide-mouth bottle made of Teflon (registered trademark) containing a magnetic stir bar, and 0.66 g of resorcinol (20 ° C.) was stirred with a magnetic stirrer. Wako Pure Chemical Industries, Ltd.) and 0.2 g of the block copolymer (Z-1) obtained in Synthesis Example 2 were sequentially added and dissolved. While continuing stirring, 0.63 g of 37% by weight formalin aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd.) was added to this solution, and after capping the wide-mouthed bottle, stirring was further performed at 20 ° C. for 24 hours. A mixture comprising a liquid containing the obtained solid was obtained (first step). The resulting mixture was allowed to stand at room temperature for 12 hours to remove most of the solvent by natural drying, and further heated at 90 ° C. for 36 hours to remove the solvent to obtain a solid (second step). ). Next, the obtained solid was heated to 500 ° C. at a rate of 1.4 ° C./min in a nitrogen atmosphere and heated at 500 ° C. for 3 hours to obtain 0.37 g of powdered porous carbon (Q-1). Was obtained (third step). The specific surface area 295m ² / g of the porous carbon (Q-1), Vmicro is 0.06cm ³ / g, Vmeso is 0.17cm ³ / g, Vmacro is 0.02cm ³ / g, Vtotal is 0.25 cm ³ / G. Observation of the porous carbon (Q-1) with a scanning electron microscope confirmed uniform pores of about 20 nm.

  Next, chemical activation of porous carbon (Q-1) was performed. Specifically, 0.3 g of the obtained porous carbon (Q-1) and 28 g of 1M aqueous potassium hydroxide solution were added to a 50 mL wide-mouth bottle made of Teflon (registered trademark) containing a magnetic stir bar, and the lid And stirred for 6 hours at 90 ° C. using a magnetic stirrer (step 4-1). Next, the solvent was removed by opening the lid and heating at 90 ° C. for 24 hours to obtain 2.4 g of a solid (step 4-2). The obtained solid was heated to 500 ° C. at a rate of 12.8 ° C./min in a nitrogen atmosphere, heated at 500 ° C. for 1 hour, and then cooled to room temperature at a rate of 12.8 ° C./min to obtain activated carbon. Obtained (step 4-3). The obtained activated carbon was washed with water until the pH of the filtrate reached 7, and then dried at 90 ° C.

Example 2
Powdered porous carbon (Q-) was obtained in the same manner as in Example 1 except that 0.2 g of the block copolymer (Z-2) was used instead of 0.2 g of the block copolymer (Z-1). 2) 0.36 g was obtained. The specific surface area of the obtained porous carbon (Q-2) is 373 m ² / g, Vmicro is 0.07 cm ³ / g, Vmeso is 0.24 cm ³ / g, Vmacro is 0.04 cm ³ / g, and Vtotal is 0. It was .35 cm ³ / g. Observation of porous carbon (Q-2) with a scanning electron microscope and a transmission electron microscope confirmed uniform pores of about 20 nm (FIGS. 1 and 2).

  Then, in place of 0.3 g of porous carbon (Q-1), chemical activation and the obtained activated carbon were performed in the same manner as in Example 1 except that 0.3 g of porous carbon (Q-2) was used. Water washing and drying were performed.

Example 3
In the third step, powdery porous carbon (Q-3) was obtained in the same manner as in Example 1 except that the temperature was raised to 800 ° C. and heated at 800 ° C. for 3 hours. The resulting porous carbon (Q-3) the specific surface area of 567m ² / g, Vmicro is 0.06cm ³ / g, Vmeso is 0.23cm ³ / g, Vmacro is 0.02cm ³ / g, Vtotal 0 It was .31 cm ³ / g. Observation of porous carbon (Q-3) with a scanning electron microscope and a transmission electron microscope confirmed uniform pores of about 20 nm (FIGS. 1 and 2).

  Next, in place of 0.3 g of porous carbon (Q-1), 0.3 g of porous carbon (Q-3) was used, and in Step 4-3, the temperature was raised to 800 ° C., and 800 ° C. In the same manner as in Example 1 except that heating was performed for 1 hour, the activated carbon obtained was washed with water and dried.

Example 4
In place of 0.2 g of block copolymer (Z-1), 0.2 g of block copolymer (Z-2) was used, and in the third step, the temperature was raised to 800 ° C., and 3 at 800 ° C. Except for the time heating, it carried out similarly to Example 1, and obtained powdery porous carbon (Q-4). The resulting porous carbon (Q-4) of the specific surface area of 261m ² / g, Vmicro is 0.04cm ³ / g, Vmeso is 0.11cm ³ / g, Vmacro is 0.02cm ³ / g, Vtotal 0 It was .17 cm ³ / g. Observation of porous carbon (Q-4) with a scanning electron microscope confirmed uniform pores of about 20 nm.

  Then, in place of 0.3 g of porous carbon (Q-1), 0.3 g of porous carbon (Q-4) was used, and in Step 4-3, the temperature was raised to 800 ° C., and 800 ° C. In the same manner as in Example 1 except that heating was performed for 1 hour, the activated carbon obtained was washed with water and dried.

Example 5
To a Teflon (registered trademark) 30-mL wide-mouth bottle containing a magnetic stir bar, add 4.5 mL of THF and stir the THF with a magnetic stirrer at 20 ° C., 0.66 g of resorcinol (Wako Pure Chemical Industries, Ltd.) And 0.54 g of the block copolymer (Z-1) obtained in Synthesis Example 2 were sequentially added and dissolved. While continuing stirring, 0.62 g of 37% by weight formalin aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd.) was added to this solution, and after capping the wide-mouthed bottle, stirring was performed at 30 ° C. for 4 hours. A liquid mixture was obtained (first step). Using a spin coater (“ASC-4000W” manufactured by Actes Co., Ltd.) under the conditions of a rotation speed of 1000 rpm and a rotation time of 60 seconds, the obtained mixture was applied onto a silicon substrate and heated at 90 ° C. for 1 hour. Was removed to obtain a thin film (that is, a solid) (second step). Next, the solid was heated to 500 ° C. at a rate of 1.4 ° C./min in a nitrogen atmosphere and heated at 500 ° C. for 3 hours to obtain thin film-like porous carbon (Q-5) (third Process). Observation of porous carbon (Q-5) with a scanning electron microscope and a transmission electron microscope confirmed uniform pores of about 20 nm (FIGS. 1 and 2).

  Next, in place of 0.3 g of porous carbon (Q-1), 0.3 g of thin film-like porous carbon (Q-5) was used, and in step 4-3, the temperature was raised to 800 ° C. Except for heating at 800 ° C. for 1 hour, chemical activation and water washing and drying of the obtained activated carbon were performed in the same manner as in Example 1.

Comparative Example 1
To a Teflon (registered trademark) 30 mL wide-mouth bottle containing a magnetic stir bar, 7.0 g of nonionic block copolymer (“F127” manufactured by BASF, number average molecular weight 12600) and 40 g of ethanol were added. A solution was prepared by stirring with a magnetic stirrer. While continuing stirring, 6.6 g of resorcinol (manufactured by Wako Pure Chemical Industries, Ltd.) was added to this solution, stirred at 20 ° C. for 30 minutes, and then 6.0 g of 37% by weight aqueous formalin solution (manufactured by Wako Pure Chemical Industries, Ltd.). And stirred at 20 ° C. for 30 minutes. While continuing stirring, 0.55 g of 5M hydrochloric acid was then added, and the mixture was further stirred for 72 hours to obtain a mixture comprising a liquid containing the precipitated solid (first step). Most of the solvent was removed by natural drying by allowing the resulting mixture to stand at room temperature for 12 hours, and then the solvent was removed by heating at 90 ° C. for 36 hours to obtain a solid (second step). . Next, the solid was heated to 800 ° C. at a rate of 1.4 ° C./min under a nitrogen atmosphere and heated at 800 ° C. for 3 hours to obtain 0.46 g of powdery porous carbon (Q-6). (Third step). The specific surface area 694m ² / g of the porous carbon (Q-6), Vmicro is 0.16cm ³ / g, Vmeso is 0.48cm ³ / g, Vmacro is 0.02cm ³ / g, Vtotal is 0.66 cm ³ / G. Observation of porous carbon (Q-6) with a scanning electron microscope confirmed uniform pores of about 6 nm.

  Then, in place of 0.3 g of porous carbon (Q-1), 0.3 g of porous carbon (Q-6) was used, and in Step 4-3, the temperature was raised to 800 ° C., and 800 ° C. In the same manner as in Example 1 except that heating was performed for 1 hour, the activated carbon obtained was washed with water and dried.

Comparative Example 2
Commercially available activated carbon (“SX-II” manufactured by Norit, specific surface area 1047 m ² / g, Vmicro is 0.43 cm ³ / g, Vmeso is 0.24 cm ³ / g, Vmacro is 0.34 cm ³ / g, and Vtotal is 1 In order to further increase the specific surface area of 0.01 cm ³ / g), in place of 0.3 g of porous carbon (Q-1), 0.3 g of the activated carbon is used, and in step 4-3, up to 800 ° C. Except that the temperature was raised and the mixture was heated at 800 ° C. for 1 hour, in the same manner as in Example 1, the chemical activation and the activated activated carbon were washed with water and dried.

  Table 1 shows data on the specific surface area, pore volume and capacitance of the activated carbon measured by the method described above. Table 1 also shows the copolymer used and the activation conditions in Step 4-3.

  From the results shown in Table 1, the electric double layer capacitors obtained using the activated carbons of Examples 1 to 5 have a higher capacitance than the electric double layer capacitors obtained using the activated carbons of Comparative Examples 1 and 2. I understand that.

Claims (5)

The manufacturing method of activated carbon characterized by including the following 1st processes-4th processes:
Hydrophobic block (T) containing a structural unit derived from an aromatic vinyl compound and having a sulfo group and a structural block derived from an unsaturated hydrocarbon compound and being amorphous A block copolymer (Z) having
Phenols,
With formaldehyde,
A first step of mixing with a solvent to obtain a mixture;
A second step of removing the solvent from the resulting mixture to obtain a solid;
A third step of heating the obtained solid to obtain porous carbon; and a fourth step of activating the obtained porous carbon to obtain activated carbon.   The manufacturing method of the activated carbon of Claim 1 which heats the obtained solid substance at the temperature of 300-1200 degreeC in a 3rd process. The method for producing activated carbon according to claim 1 or 2, wherein the fourth step includes the following steps 4-1 to 4-3:
The resulting porous carbon;
An alkali metal hydroxide,
Step 4-1 for obtaining a dispersion by mixing with a solvent;
Step 4-2 for removing the solvent from the obtained dispersion to obtain a solid; and Step 4-3 for obtaining activated carbon by heating the obtained solid at a temperature of 400 to 900 ° C.   Activated carbon obtained by the production method according to claim 1. The activated carbon according to claim 4, wherein the specific surface area is 1000 m ² / g or more and the total pore volume is 0.3 cm ³ / g or more.