JP2008308360A - Manufacturing method of carbon material for electric double layer capacitor electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient manufacturing method of a carbon material for an electric double layer capacitor electrode having a high electrostatic capacity per unit volume. <P>SOLUTION: In the manufacturing method of the carbon material for the electric double layer capacitor electrode, easily graphitizable coke is heated and nitrided by a nitriding reaction under a nitrogen-containing gas flow and then treated for activation. When the nitriding reaction is performed, a nitriding reaction apparatus equipped with a heater and a vertically set reactor having a gas introducing part and a gas exhausting part is used. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a carbon material for an electric double layer capacitor electrode.

  An electric double layer capacitor (hereinafter referred to as EDLC) is capable of charging / discharging a large current, has a long life and is excellent in high-temperature stability, and therefore has ideal characteristics as a power storage device such as a hybrid vehicle. However, the conventional EDLC has the only drawback that the energy density is insufficient. Therefore, as a polarizable electrode carbon material for EDLC, instead of activated carbon activated by steam, carbon dioxide, etc., from conventional coconut straw, coke, phenol resin, etc., graphitizable coke, mesocarbon microbeads, or mesophase pitch A high-capacitance activated carbon obtained by activation using an alkali metal compound from graphitizable carbon such as a carbon fiber (hereinafter referred to as alkali activation) has been proposed (see, for example, Patent Documents 1 to 3). .

  Moreover, it is disclosed that an activated carbon for EDLC excellent by activating the easily graphitizable coke obtained by heat-treating a specific raw material pitch can be obtained (for example, see Patent Documents 4 and 5). It is becoming clear that the selection of starting materials and processing conditions for activation is important for obtaining activated carbon with high capacitance. However, electric double layer capacitors using alkali-activated activated carbon of graphitizable coke are disadvantageous in that the capacitance density decreases greatly during repeated use. There is a demand for a carbon material for an electric double layer capacitor electrode that increases the energy density by increasing the energy density.

  As a means to solve this problem, it has been found that a carbon material for an electric double layer capacitor electrode that gives a high energy density can be obtained by heat-treating coke under specific conditions before the activation treatment (patent) Reference 6). In particular, a carbon material for an electric double layer capacitor electrode exhibiting excellent characteristics can be obtained by heat-treating graphitizable coke at a temperature of 550 to 1000 ° C. in an atmosphere containing ammonia gas and then activating it. It is disclosed.

On the other hand, the reaction between coke and ammonia gas as described above needs to suppress side reactions typified by the decomposition reaction of ammonia, and the coke, which is a granular or powdered solid, is brought into contact with ammonia gas efficiently. Although there are many points to be solved industrially, such as the necessity of performing a reaction and that ammonia is a corrosive gas, a specific method is not disclosed. There is a need for a method that can realize high electrostatic capacity density by mass-producing graphitizable coke efficiently by nitriding with nitrogen-containing gas typified by ammonia gas, and enabling mass production at low cost.
Japanese Patent No. 2548546 Japanese Patent No. 2634658 Japanese Patent No. 3149504 Japanese Patent Laid-Open No. 2002-93667 JP 2001-180923 A JP 2006-12938 A

  An object of the present invention is to solve the above problems and to provide a method for efficiently producing a carbon material for an EDLC electrode having a high electrostatic capacity per unit volume.

As a result of a detailed study of a method capable of efficiently reacting ammonia gas, which is one of nitrogen-containing gases, and graphitizable coke, and mass production at low cost, the following problems have been solved. It became clear.
(1) Since ammonia gas undergoes a decomposition reaction into hydrogen and nitrogen at a high temperature of 500 ° C. or higher, it is necessary to bring ammonia gas and graphitizable coke into contact quickly and efficiently.
(2) When iron or stainless steel coexists in the reaction system, the ammonia gas decomposition reaction is further accelerated, and it becomes substantially difficult to treat graphitizable coke.
As a reaction apparatus for solving these problems, a rotary kiln in which a reactor (retort) is made of ceramic or carbon can be considered. Usually, the filling rate of the retort is about 10% by volume at most, and 20% by volume even in a batch. Since it is difficult to manufacture a large size ceramic or carbon retort, the processing capacity per unit is reduced and the cost is increased. Further, the contact efficiency between ammonia gas and graphitizable coke is not sufficient.

  In addition, there is a roller hearth kiln that can be easily heat-treated by filling the container with graphitizable coke, but the contact efficiency between ammonia gas and graphitizable coke is poor and the filling amount cannot be increased. The size becomes very large and a large amount of implantation gas is required, resulting in high cost.

Therefore, the present inventors have overcome the above problems and devised a method capable of efficiently reacting a nitrogen-containing gas typified by ammonia gas and easily graphitizable coke, resulting in high productivity and low cost, and reached the present invention. That is, the present invention is as follows.
1. A method for producing a carbon material, in which an easily graphitizable coke is heated in a nitrogen-containing gas flow and converted into a nitride by a nitriding reaction, and then subjected to an activation treatment. In performing the nitriding reaction, a heating device, a gas introduction unit And a method for producing a carbon material for an electric double layer capacitor electrode, comprising using a nitriding reaction apparatus having a gas discharge section and a vertically arranged reactor.
2. The method for producing a carbon material for an electric double layer capacitor electrode according to claim 1, wherein the nitriding reaction device comprises a device for continuously charging graphitizable coke to the reactor and a device for continuously discharging from the reactor.
3. The method for producing a carbon material for an electric double layer capacitor electrode according to claim 1 or 2, wherein the material constituting the inner wall portion of the reactor is ceramic or carbon.
4). The method for producing a carbon material for an electric double layer capacitor electrode according to any one of Items 1 to 3, wherein the reactor has a cylindrical shape, an inner diameter of 50 to 500 mm, and a length of 500 to 5000 mm.
5. The method for producing a carbon material for an electric double layer capacitor electrode according to any one of Items 1 to 4, wherein the nitrogen-containing gas is circulated by upflow or downflow.
6). The method for producing a carbon material for an electric double layer capacitor electrode according to any one of Items 1 to 5, wherein the graphitizable coke is produced by the following steps (a) and (b).
(A) In a heat treatment apparatus maintained at a temperature of 400 ° C. or more and 700 ° C. or less, a plurality of particles made of metal or ceramics are charged and flown, and a raw material pitch is supplied into the apparatus to perform heat treatment. A step of attaching coke to the surface of the granular material by
(B) The process of isolate | separating coke from this granular material by heating the coke adhering to this granular material surface to the temperature higher than the heat processing temperature in process (a), and 900 degrees C or less.
7). The graphitizable coke is obtained by heat-treating the raw material pitch at 500 to 1000 ° C. so as to have an expansion rate of 1000% or more, and the graphitizable coke has a fine diameter of 1 μm or less by a mercury intrusion method. The method for producing a carbon material for an electric double layer capacitor electrode according to any one of Items 1 to 5, wherein the pore volume is 0.18 cc / g or less.
8). The electric graphite according to any one of Items 1 to 5, wherein the graphitizable coke is produced from a pitch obtained by polymerizing a condensed polycyclic hydrocarbon in the presence of hydrogen fluoride and boron trifluoride. Manufacturing method of carbon material for multilayer capacitor electrode.
9. The method for producing a carbon material for an electric double layer capacitor electrode according to any one of Items 1 to 8, wherein the nitrogen-containing gas is a gas containing 0.1 to 100% by volume of ammonia.
10. The activation process is performed by adding 1 to 6 parts by weight of an alkali metal compound to 1 part by weight of nitride and heating in a temperature range of 400 to 1000 ° C. in an inert gas stream. The manufacturing method of the carbon material for electric double layer capacitor electrodes in any one of claim | items.
11. A nitriding reaction apparatus comprising a heating apparatus, a gas introduction section and a gas discharge section, and a reactor arranged in a vertical shape, wherein the graphitizable coke is heated under a nitrogen-containing gas flow.

According to the present invention, activated carbon for EDLC electrodes having a high electrostatic capacity per unit volume can be produced at a low cost, and thus the industrial significance is extremely large. By using this material, an EDLC with a high energy density can be realized, which is very useful as a power source for hybrid vehicles, UPSs, and the like.
In addition, according to the present invention, the graphitized coke is filled in a vertically arranged reactor, and the heat treatment is performed while flowing a nitrogen-containing gas, so that the efficiency of the nitriding reaction and the volume capacity of the apparatus can be improved. it can.

  The present invention relates to a method for producing a carbon material for an EDLC electrode capable of obtaining a high capacitance per unit volume, and an activation treatment is performed after a nitrogen-containing gas and a graphitizable coke are efficiently reacted and subjected to nitriding treatment. Thus, the present invention provides a method for mass-producing a carbon material having a high capacitance density at low cost.

  In carrying out the nitriding treatment of graphitizable coke, the present invention is carried out by using a nitriding reactor equipped with a reactor having a heating device, a gas introduction part, and a gas discharge part and arranged vertically.

  The graphitizable coke used in the present invention is obtained by carbonization using petroleum-based pitch, coal-based pitch or synthetic pitch as a starting material. Preferable examples for obtaining a high capacitance electrode include naphthalene and methylnaphthalene, as disclosed in Japanese Patent No. 2931593, Japanese Patent No. 2612253, Japanese Patent No. 2526585, or Japanese Patent Application Laid-Open No. 2000-319664. , Synthetic pitches obtained by polymerizing condensed polycyclic hydrocarbons such as anthracene, phenanthrene, acenaphthene, acenaphthylene, and pyrene in the presence of hydrogen fluoride and boron trifluoride as super strong acid catalysts. Unlike other pitches, these are particularly preferably used because they have high chemical purity and the properties can be freely controlled.

When a non-graphitizable coke derived from a non-graphitizable resin or the like is used, it is not preferable because it is easily activated and the electrode density is greatly reduced. The method for obtaining graphitizable coke from the raw material pitch is not particularly limited, but productivity is achieved by flowing a metal or ceramic granular material in a heat treatment apparatus, attaching the raw material pitch to the apparatus, and carbonizing the material. And preferable in terms of characteristics. That is, it is a method for producing coke including the following steps (a) and (b).
(A) In a heat treatment apparatus maintained at a temperature of 400 ° C. or more and 700 ° C. or less, a plurality of particles made of metal or ceramics are charged and flown, and a raw material pitch is supplied into the apparatus to perform heat treatment. A step of attaching coke to the surface of the granular material by
(B) The process of isolate | separating coke from this granular material by heating the coke adhering to this granular material surface to the temperature higher than the heat processing temperature in process (a), and 900 degrees C or less.

  In addition, it is preferable to use coke obtained by heat-treating the raw material pitch at 500 to 1000 ° C. so that the expansion coefficient is 1000% or more in order to obtain a high capacitance. Furthermore, it is very high by using graphitizable coke which is obtained so as to have an expansion rate of 1000% or more and has a pore volume of 1 μm or less by a mercury intrusion method and 0.18 cc / g or less. Capacitance is obtained.

  In particular, coke obtained with an expansion rate of 1000% or more has a thin carbon film shape, and even if rapid heating, rapid cooling, or activation treatment is performed due to this special thin shape, cracks and the like are generated inside the particles. Since there is no defect and it becomes scaly after pulverization, it has an advantage that the electrode density of the EDLC electrode tends to be high. Furthermore, the optical structure of the coke has a flow structure, and has many structural features that contribute to increasing the density of the EDLC electrode, such that defects do not easily exist inside the particles.

  The scaly coke obtained in this way is characterized by a small number of pores of 1 μm or less that are not involved in the electric double layer capacity development. In order to obtain the pore volume in this region, it can be obtained by a mercury intrusion method. The pore volume of 1 μm or less measured by mercury porosimetry is preferably 0.18 cc / g or less, more preferably 0.16 cc / g or less, still more preferably 0.15 cc / g or less.

  The coke used for the nitriding treatment preferably has an elemental analysis of H / C of 0.40 or less or a true density of 1.42 g / cc or more, more preferably H / C of 0.38 or less and a true density of 1.425. More preferably, H / C is 0.36 or less and true density is 1.43 or more. When H / C is higher than 0.40 and the true density is lower than 1.42 g / cc, the density of the EDLC electrode by the carbon material after nitriding and activation is likely to decrease, resulting in a high capacitance. I can't get it.

  The carbon material having a high electrode density and a high capacitance in the present invention is brought about by the changing nitrogen content until the carbon material is prepared. That is, nitrogen in coke is reduced by being activated to form a pore structure. Nitrogenized coke (nitride) has different carbon material properties depending on the amount of hydrogen and nitrogen contained, and H / C and N / C by elemental analysis are 0.15 or more and 0.016 or more, respectively. Is preferred. When these values are too low, the formation of the pore structure by activation is inhibited, and a high capacitance is not exhibited.

  Nitrogen introduced by the nitriding reaction is released by the activation of the nitride. As a result, a high capacitance can be obtained, but it is preferable that the difference in nitrogen content between the coke after the nitriding reaction and the activated carbon material is 1% or more, more preferably 1.2% or more, and further Preferably it is 1.5% or more. When the difference in the nitrogen content is 1% or less, the number of pores to be formed is small, and the resulting capacitance is low.

  The carbon material for an EDLC electrode according to the present invention is characterized in that a high-density electrode can be obtained because nitriding is performed at a high temperature. In this case, the Gakushin method (Japan Society for the Promotion of Science carbon material no. A high-density electrode can be obtained in a carbon material having a large Lc value obtained from the 002 diffraction peak when analyzed based on the 117 committee). Specifically, those showing a large value of 10 nm or more are preferable, more preferably 10.5 nm, and still more preferably 11 nm or more.

  As the nitrogen-containing gas used in the present invention, any nitrogen-containing compound that is gaseous from room temperature to the reaction temperature can be used, such as ammonia, hydrogen cyanide, amines such as methylamine, ethylamine, and aniline, pyridine, quinoline, and the like. And nitrogen-containing aromatic compounds. Of these, ammonia is preferably used in terms of reactivity and cost. The nitrogen-containing gas may be diluted with an inert gas such as nitrogen or argon, and the concentration of the nitrogen-containing gas in the gas introduced into the reactor is preferably 0.1 to 100 vol%, more preferably 5 to 5%. It is 100 vol%, More preferably, it is 30-100 vol%.

  Regarding the temperature of the nitriding reaction, the capacitance is not improved if it is too high or too low. If the heat treatment temperature is too high, the carbon network surface develops too much and the formation of the pore structure by activation is inhibited. If it is too low, the nitriding reaction will not proceed sufficiently. The temperature is preferably 500 to 1000 ° C, more preferably 600 to 900 ° C, and still more preferably 600 to 850 ° C. The time for the nitriding reaction is preferably 0.1 to 10 hours, more preferably 0.1 to 4 hours, and further preferably 0.5 to 2 hours.

  The material constituting the inner wall portion of the reactor in the nitriding reactor is preferably ceramic or carbon. For example, in the case of a cylindrical shape, the reactor preferably has an inner diameter of 50 mm to 500 mm and a length of 500 mm to 5000 mm. If the inner diameter or the maximum width of the cross section is too small, the amount of treatment is insufficient, and if it is too large, the thermal conductivity of the graphitizable coke is not necessarily high, so that the processing temperature in the cross section direction becomes nonuniform. If the length is too short, the amount of treatment is insufficient. If the length is too long, the pressure loss in the pipe increases, and the amount of gas that can be circulated is restricted, which is not preferable.

  The shape of the reactor is not limited, and the cross section may be any of a circle, an ellipse, or a polygon, but a circle is preferable from the viewpoint of uniform heating and quick movement of graphitizable coke.

  Further, the direction in which the nitrogen-containing gas is circulated may be either up-flow or down-flow, and can be appropriately selected depending on the particle size of the graphitizable coke and processing conditions.

  For nitriding treatment of graphitizable coke, a nitriding reaction apparatus including a heating apparatus, a gas introduction part, a gas discharge part and a reactor arranged in a vertical shape is used. The nitriding reactor preferably comprises a device for continuously charging graphitizable coke into the reactor and a device for continuously discharging from the reactor.

  The shape of the coke at the time of reacting the nitrogen-containing gas and the graphitizable coke is not limited, but fine particles are desirable to increase the efficiency of the nitriding reaction. The particle diameter is preferably 10 mm or less, more preferably 3 mm or less. In addition, in order to reduce the pressure loss in the reactor and to move the treated material uniformly in the reactor, granulation is performed by selecting an appropriate binder and forming an appropriate particle size or shape. May be.

  The resulting nitride is activated after grinding. As a method for pulverizing nitride, there are a ball mill, a roller mill, a high-speed rotating mill, a medium stirring mill, a jet mill and the like. Any pulverizer may be used, and a plurality of pulverizers and classifiers may be used in combination in order to obtain a desired particle size.

  Although there is no particular limitation on the particle size to be obtained, the EDLC electrode is usually several hundred μm, and even when it is thick, it is 500 μm or less. From the viewpoint of handling, the lower limit of the particle size is preferably 100 nm or more. Therefore, the recommended particle size as a nitride as a precursor of the carbon material for EDLC electrodes is 100 nm to 500 μm, preferably 200 nm to 200 μm, and more preferably 500 nm to 100 μm.

  In order to obtain a high capacitance, chemical activation is preferable. In particular, alkali activation using an alkali metal compound is preferred. As an activator used for alkali activation, alkali metal compounds such as lithium hydroxide, sodium hydroxide, potassium hydroxide, potassium carbonate, and potassium chloride are used. Of these, sodium hydroxide, potassium hydroxide, or a combination thereof is preferable.

  Although the alkali activation method and apparatus are not particularly limited, 1 to 6 parts by weight of alkali metal compound is added to 1 part by weight of nitride, and these are uniformly mixed and filled into a container. The method of mixing is not limited as long as the nitride particles and the alkali metal compound are in uniform contact, but the method of mixing the alkali metal compound with a mixer after pulverizing the alkali metal compound, There is a method of adding to nitride particles.

  The mixture of nitride and alkali metal compound is heated from room temperature to 400 to 1000 ° C. in a heating furnace under an inert gas atmosphere such as nitrogen gas or argon gas and held for 0.5 to 20 hours. Preferably, it is held at a temperature of 500 to 900 ° C, more preferably at a temperature of 600 to 800 ° C for 1 to 5 hours. When the reaction temperature is lower than 400 ° C., the reaction hardly proceeds and the activation level does not increase. In the case of using potassium hydroxide, if it is higher than 1000 ° C., the problem of erosion of the reaction apparatus due to precipitation or scattering of metallic potassium is severe.

  After the activation treatment, the carbon material for an EDLC electrode is obtained by performing neutralization washing with hydrochloric acid and washing with water until neutrality.

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited at all by these Examples.

Example 1
In the presence of hydrogen fluoride and boron trifluoride, naphthalene is polymerized to synthesize pitch (softening point by Mettler method: 283 ° C., optical anisotropy of carbonized product: 100%, Lc value of graphitized product:> 100 nm) did.
Next, 1000 g of the pitch is placed in a stainless steel square container having a height of 400 mm and a bottom surface of 400 mm × 400 mm, heated in a vertical furnace to 730 ° C. in a nitrogen atmosphere, and held at this temperature for 1 hour. I got coke. The expansion ratio at this time was 2500%, and the pore volume of 1 μm or less of the coke was 0.11 cc / g. The coke had an H / C of 0.309 and a true density of 1.49 g / cc.
The coke was coarsely pulverized to a particle size of 2 mm or less, and 400 g of an aqueous binder solution in which 3% by weight of carboxycellulose ammonium salt (CMC) was dissolved was added to 600 g of coke, and granulated to a size of about 10 mm.
A vertical continuous nitriding reactor (furnace core tube: made of alumina, inner diameter 50 mm, height 1500 mm, heating device: electric furnace, heating zone 1000 mm) as shown in FIG. 2 is used, and the granulated coke is heated at 1 kg per hour. Coke nitriding was carried out while moving from the top to the bottom with an internal residence time of 2 hours, and flowing 100 vol% ammonia gas from the bottom at a rate of 0.13 m ³ per hour. The temperature in the furnace was kept at 750 ° C. H / C and N / C of the obtained nitride were 0.169 and 0.0449, respectively.
1 part by weight of the nitride powder (pulverized to 32 μm or less) and 1.8 parts by weight of 95% potassium hydroxide were uniformly mixed, and the temperature was raised to 750 ° C. at 5 ° C./min under a nitrogen atmosphere. Hold at temperature for 3 hours. After cooling to room temperature, the mixture was poured into a methanol-water mixture, and acid washing with 0.1 mol / L hydrochloric acid aqueous solution, filtration, and water washing were repeated until the filtrate became neutral. The difference in nitrogen content between the nitride and the obtained carbon material was 4.3%, and the Lc of the carbon material was 11.7 nm.
The carbon material was mixed at a weight ratio of carbon material: conductive filler (Denka black): binder (Teflon (registered trademark)) 80:10:10 to prepare an electrode. For electrode evaluation, an aluminum bipolar cell was used, and a paper separator was sandwiched between a pair of electrodes and accommodated in the cell. As the electrolyte, propylene carbonate in which 1.8 mol / L of triethylmethylammonium tetrafluoroborate ((C ₂ H ₅ ) ₃ CH ₃ NBF ₄ ) was dissolved was used.
Charged to a voltage of 2.7 V at a constant current of 100 mA / g in an argon gas atmosphere at room temperature, further charged for 2 hours at 2.7 V, then discharged to 0 V at a constant current of 100 mA / g. The capacitance was calculated from the amount of electricity. The capacitance was calculated according to the following formula based on the weight of carbon in the positive and negative electrodes (activated carbon and acetylene black). The capacitance Cv (F / cc) per volume was calculated by multiplying the capacitance Cw (F / g) per weight by the electrode density.
(Formula) Capacitance Cw (F / g) = Discharge Electricity (AH / g) × 3600 / 2.7
As a result, the capacitance per weight was 39.3 F / g, the capacitance per volume was 41.6 F / cc, and the electrode density was 1.06 g / cc.

Example 2
The pitch used in Example 1 was continuously supplied to a rotary kiln (with an internal volume of 0.15 m ³ ) containing 81 kg of zirconia balls, coked at 550 ° C., and then kept at 685 ° C. for 1 hour for heat treatment. After allowing to cool, the coke and zirconia balls were separated from the rotary kiln. The coke had an H / C of 0.295 and a true density of 1.50 g / cc.
In the same manner as in Example 1, the coke was coarsely pulverized to a particle size of 2 mm or less, and 5 kg of a binder aqueous solution in which 3% by weight of CMC was dissolved was added to 10 kg of coke, and granulated to a size of about 10 mm.
A vertical continuous nitriding reactor (furnace core tube: made of alumina, inner diameter 50 mm, height 1500 mm, heating device: electric furnace, heating zone 1000 mm) as shown in FIG. 2 is used, and the granulated coke is heated at 1 kg per hour. The coke was nitrided while moving from the top to the bottom with an internal residence time of 2 hours and with 100 volume% ammonia gas flowing from the bottom at a rate of 0.13 m ³ per hour. The temperature in the furnace was kept at 750 ° C.
After heat treatment with ammonia, it was pulverized to 32 μm or less. The H / C and N / C of the nitrided coke (nitride) were 0.164 and 0.0252, respectively. A carbon material was obtained from the nitride in the same manner as in Example 1. The difference in nitrogen content between the nitride and the carbon material was 2.3%, and the Lc of the carbon material was 11.9 nm.
The capacitance per weight was 37.3 F / g, the capacitance per volume was 37.3 F / cc, and the electrode density was 1.00 g / cc.

Schematic diagram of vertical furnace Schematic diagram of continuous vertical furnace

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas introduction part or gas discharge part 2 Reactor 3 Heating device 4 Gas discharge part or gas introduction part 5 Coke continuous input part 6 Gas introduction part or gas discharge part 7 Reactor 8 Heating device 9 Gas discharge part or gas introduction part 10 Coke continuous discharge unit

Claims (11)

  A method for producing a carbon material, in which an easily graphitizable coke is heated in a nitrogen-containing gas flow and converted into a nitride by a nitriding reaction, and then subjected to an activation treatment. In performing the nitriding reaction, a heating device, a gas introduction unit And a method for producing a carbon material for an electric double layer capacitor electrode, comprising using a nitriding reaction apparatus having a gas discharge section and a vertically arranged reactor.   The method for producing a carbon material for an electric double layer capacitor electrode according to claim 1, wherein the nitriding reactor comprises a device for continuously charging graphitizable coke to the reactor and a device for continuously discharging from the reactor.   The method for producing a carbon material for an electric double layer capacitor electrode according to claim 1 or 2, wherein the material constituting the inner wall portion of the reactor is ceramics or carbon.   The method for producing a carbon material for an electric double layer capacitor electrode according to any one of claims 1 to 3, wherein the reactor has a cylindrical shape, and has an inner diameter of 50 to 500 mm and a length of 500 to 5000 mm.   The method for producing a carbon material for an electric double layer capacitor electrode according to any one of claims 1 to 4, wherein the nitrogen-containing gas is circulated by upflow or downflow. The method for producing a carbon material for an electric double layer capacitor electrode according to any one of claims 1 to 5, wherein the graphitizable coke is produced by the following steps (a) and (b).
(A) In a heat treatment apparatus maintained at a temperature of 400 ° C. or more and 700 ° C. or less, a plurality of particles made of metal or ceramics are charged and flown, and a raw material pitch is supplied into the apparatus to perform heat treatment. A step of attaching coke to the surface of the granular material by
(B) The process of isolate | separating coke from this granular material by heating the coke adhering to this granular material surface to the temperature higher than the heat processing temperature in process (a), and 900 degrees C or less.   The graphitizable coke is obtained by heat-treating the raw material pitch at 500 to 1000 ° C. so as to have an expansion rate of 1000% or more, and the graphitizable coke has a fine diameter of 1 μm or less by a mercury intrusion method. The method for producing a carbon material for an electric double layer capacitor electrode according to claim 1, wherein the pore volume is 0.18 cc / g or less.   6. The electric double layer capacitor according to claim 1, wherein the graphitizable coke is produced from a pitch obtained by polymerizing a condensed polycyclic hydrocarbon in the presence of hydrogen fluoride and boron trifluoride. A method for producing a carbon material for an electrode.   The method for producing a carbon material for an electric double layer capacitor electrode according to any one of claims 1 to 8, wherein the nitrogen-containing gas is a gas containing 0.1 to 100% by volume of ammonia.   The activation process is performed by adding 1 to 6 parts by weight of an alkali metal compound to 1 part by weight of nitride and heating in a temperature range of 400 to 1000 ° C under an inert gas stream. The manufacturing method of the carbon material for electric double layer capacitor electrodes in any one.   A nitriding reaction apparatus comprising a heating apparatus, a gas introduction section and a gas discharge section, and a reactor arranged in a vertical shape, wherein the graphitizable coke is heated under a nitrogen-containing gas flow.

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