JP2004290810A - Hydrogen storage material and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen storage material capable of stably storing a large amount of hydrogen even under a normal temperature and low pressure condition and having a low hydrogen discharge temperature, and its manufacturing method. <P>SOLUTION: The hydrogen storage material is constituted of a carbonaceous material micronized by mechanical grinding under a hydrogen gas atmosphere and a metal having a function for dissociating a hydrogen molecule into hydrogen atoms. Preferably, the hydrogen storage material is constituted by supporting the metal having the function for dissociating the hydrogen molecule into hydrogen atoms on the carbonaceous material micronized by mechanical grinding under the hydrogen gas atmosphere. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００３６】
表１および図１に示すように、触媒を担持させた実施例１〜１７は、常温・定圧でも十分に水素を貯蔵することができ、触媒を担持させなかった比較例１に比べて水素放出開始温度が低くなり水素貯蔵量も多くなることが確認された。
【００３７】
また、実施例のうち、グラファイトの微細化前に触媒を担持させた実施例１１〜１７は、水素放出開始温度が２７０〜２９０℃、水素貯蔵量が圧力１ＭＰａで２．８８〜３．６５ｍａｓｓ％、６ＭＰａで３．５２〜４．２７ｍａｓｓ％であり、比較例１の水素放出開始温度３１５℃、水素貯蔵量１ＭＰａで２．８７〜３．３０ｍａｓｓ％、６ＭＰａで３．４６〜３．８９ｍａｓｓ％よりも小幅な改善であったのに対し、グラファイトを微細化後に触媒を担持させた実施例１〜１０は、水素放出開始温度が２００〜２１４℃、水素貯蔵量が１ＭＰａで３．２７〜５．０９ｍａｓｓ％、６ＭＰａで３．９３〜６．００ｍａｓｓ％となり、水素放出温度および水素貯蔵量が大幅に改善されたことが確認された。
【００３８】
実験に用いた触媒種の中では、Ｐｄを用いた実施例９および１０の効果が高く、水素放出開始温度が２００℃、水素貯蔵量が１ＭＰａで４．６〜５．１ｍａｓｓ％程度、６ＭＰａで５．５〜６．０ｍａｓｓ％程度となった。
【００３９】
【発明の効果】
以上説明したように、本発明によれば、水素貯蔵材料である水素ガス雰囲気下で機械粉砕により微細化した炭素質材料と、水素分子を水素原子に解離させる機能を有する触媒としての金属とを用いて水素貯蔵材を構成するので、常温・低圧でも多量の水素を安定して貯蔵することができ、かつ水素放出温度を低下させることができる。また、水素分子を水素原子に解離させる機能を有する金属を、炭素質材料を微細化する前ではなく微細化した後に担持させることにより、水素放出温度の低下効果をより高めることができるとともに、水素貯蔵量をより高めることができる。
【図面の簡単な説明】
【図１】実施例および比較例の水素放出曲線および水素貯蔵量の積算値を示す図。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hydrogen storage material capable of storing a large amount of hydrogen at normal temperature and low pressure, and a method for producing the same. More specifically, the present invention relates to a method for storing or comparing a large amount of hydrogen at normal temperature and low pressure using a carbonaceous material such as graphite. TECHNICAL FIELD The present invention relates to a hydrogen storage material that releases hydrogen at a relatively low temperature and a method for producing the same.
[0002]
[Prior art]
Due to the depletion of fossil fuels and global environmental problems, natural energy and renewable energy are promising as secondary energy alternatives to fossil fuels. In particular, hydrogen gas is expected to be an important material in the energy cycle.
[0003]
As a method of storing hydrogen, a method of storing as liquid hydrogen or a compressed gas, and a storage using a hydrogen storage alloy or the like are known. However, all of them have the following disadvantages.
[0004]
In other words, in the method of storing hydrogen as a liquid, it is necessary to cool the hydrogen to a very low temperature, so that the energy consumption required for liquefaction is large. It has the drawback that it cannot be stored for a long period of time. In the method of storing hydrogen gas as a compressed gas, it is necessary to increase the pressure to increase the amount of hydrogen stored. Therefore, the weight of the container is increased and the pressure resistance and reliability of valves and the like are problematic. A method of storing hydrogen in a hydrogen storage alloy is to store hydrogen in a hydrogen storage alloy containing Mg, Ni, or the like as a main component. In this method, however, the amount of hydrogen stored per unit weight is small. Becomes heavy.
[0005]
Recently, attention has been paid to carbon-based materials such as carbon nanotubes and activated carbon as hydrogen storage materials for solving these problems, and active research has been conducted.
[0006]
For example, Patent Document 1 proposes a method of storing hydrogen in carbon nanotubes. Patent Literature 2 proposes a method of adsorbing hydrogen on a fine structure using activated carbon. Further, Patent Document 3 proposed by the present inventor previously proposes a hydrogen storage material having high hydrogen storage capacity using graphite nanostructured by mechanical pulverization.
[0007]
[Patent Document 1]
JP-A-11-116219 [Patent Document 2]
WO98 / 30496 [Patent Document 3]
Japanese Patent Application Laid-Open No. 2001-302224
[Problems to be solved by the invention]
However, although it is reported that the carbon nanotube of Patent Document 1 is produced by a thermal decomposition reaction and has a low yield and can store a large amount of hydrogen, it has a drawback that reproducibility cannot be obtained. Therefore, it is not preferable as an industrial production method. Further, the activated carbon of Patent Document 2 requires an extremely low temperature and a high pressure, such as a temperature of −173 ° C. or less and a hydrogen pressure of about 5 MPa, for storing hydrogen, which is not preferable as an industrial production method. On the other hand, Patent Document 3 described above can store a relatively large amount of hydrogen at normal temperature and under low pressure, but has a drawback that the temperature at which the stored hydrogen is released is high.
[0009]
The present invention has been made in view of such circumstances, and has as its object to provide a hydrogen storage material which can stably store a large amount of hydrogen even at ordinary temperature and low pressure, has a low hydrogen release temperature, and a method for producing the same. And
[0010]
[Means for Solving the Problems]
In order to solve the above problems, as a result of repeated studies by the present inventors, a carbonaceous material such as graphite, which is disclosed in Japanese Patent Application Laid-Open No. 2001-302224 and refined by mechanical pulverization under a hydrogen gas atmosphere, is used. It has been found that by using a metal having a function of dissociating hydrogen molecules into hydrogen atoms, a large amount of hydrogen can be stably stored even at room temperature and low pressure, and the hydrogen release temperature can be lowered. . In addition, by supporting a metal having a function of dissociating hydrogen molecules into hydrogen atoms after the carbonaceous material is refined rather than before the refinement, the effect of lowering the hydrogen release temperature can be further improved, and It has been found that the storage amount can be further increased.
[0011]
The present invention has been completed based on such findings of the present inventors, and provides the following (1) to (7).
[0012]
(1) A hydrogen storage material comprising: a carbonaceous material finely divided by mechanical pulverization in a hydrogen gas atmosphere; and a metal having a function of dissociating hydrogen molecules into hydrogen atoms.
(2) A hydrogen storage material characterized in that a metal having a function of dissociating hydrogen molecules into hydrogen atoms is supported on a carbonaceous material that has been refined by mechanical pulverization in a hydrogen gas atmosphere.
(3) The hydrogen storage material according to (2), wherein hydrogen is stored on the surface and / or inside of the fine carbonaceous material.
(4) In the above (1) to (3), the metal is Mn, Fe, Co, Ni, Pt, Pd, Rh, Li, B, Na, Mg, K, Ir, Nd, La, Ca, V , Ti, Cr, Cu, Zn, Al, Si, Ru, and Ag, or a hydrogen storage alloy, or a hydrogen storage alloy.
(5) In the above (1) to (4), the content of a metal having a function of dissociating the hydrogen molecule into a hydrogen atom with respect to the carbonaceous material is 0.3 to 30.0 mass%. Hydrogen storage material.
(6) a step of mechanically pulverizing the carbonaceous material in a hydrogen gas atmosphere, and a step of supporting a metal having a function of dissociating hydrogen molecules into hydrogen atoms on the carbonaceous material refined by mechanical pulverization. A method for producing a hydrogen storage material, comprising storing hydrogen on the surface and / or inside of the carbonaceous material in the process of mechanically pulverizing the carbonaceous material.
(7) The method for producing a hydrogen storage material according to (6), wherein the pressure of the hydrogen gas is 1 MPa or less.
[0013]
Embodiment of the present invention
Hereinafter, embodiments of the present invention will be described.
In the present invention, a hydrogen storage material is formed by using a carbonaceous material finely divided by mechanical pulverization in a hydrogen gas atmosphere as a hydrogen storage material, and further using a metal having a function of dissociating hydrogen molecules into hydrogen atoms as a catalyst component. I do.
[0014]
In the present invention, in the process of pulverizing a carbonaceous material typified by graphite by mechanical pulverization in a hydrogen gas atmosphere, hydrogen penetrates the micronized carbonaceous material, and Hydrogen is stored on the surface and / or inside. Here, the term “inside” means between crystal grains, between layers, and in defects. There are two types of hydrogen invasion, one with a carbon-hydrogen covalent bond and the other without a covalent bond. Among these, hydrogen mainly without a covalent bond can be reversibly extracted and used as storage hydrogen. It is valid.
[0015]
As the carbonaceous material, graphite, amorphous carbon, activated carbon and the like can be used. Among them, graphite is preferable because of its large hydrogen storage capacity. Since graphite crystals have a layered structure, a large amount of hydrogen can be stored between the surfaces and between layers during the pulverization process in a hydrogen atmosphere.
[0016]
In the technique disclosed in Patent Document 3 (Japanese Patent Application Laid-Open No. 2001-302224), hydrogen is stored in the process of pulverizing graphite in a hydrogen atmosphere as described above. ° C, and the maximum amount of hydrogen storage is about 3 mass%. However, it is required to lower the expression temperature of hydrogen and further increase the amount of hydrogen storage.
[0017]
Therefore, in the present invention, a metal having a function of dissociating hydrogen molecules into hydrogen atoms is used as a catalyst component. By the action of such a metal, the taken-in hydrogen molecules are dissociated into hydrogen atoms, and the effect of reducing the hydrogen release temperature and increasing the hydrogen storage amount can be obtained. The catalyst component is not particularly limited as long as it is a metal or an alloy having such a function. Mn, Fe, Co, Ni, Pt, Pd, Rh, Li, B, Na, Mg, K, Ir, Nd , La, Ca, V, Ti, Cr, Cu, Zn, Al, Si, Ru and Ag, or a hydrogen storage alloy. Of these metals, Pd is particularly good. Hydrogen storage alloys are basically endothermic metals B having no affinity between hydrogen and exothermic metals A (for example, Ti, Zr, misch metal (Mm), Ca, etc.) that easily form stable hydrides. (e.g., Ni, Fe, Co, Mn, etc.) are composed of, AB ₅ type (LaNi ₅ or MmNi _5, etc.), AB ₂ type _(e.g., Ti 1.2 _{Mn 1.8} and _{TiCr 1.8} etc. ), AB type (such as TiFe) and A ₂ B type (such as Mg ₂ Ni and Mg ₂ Cu).
[0018]
The content of the metal as a catalyst component as described above is preferably 0.3 to 30.0 mass% with respect to the carbonaceous material. If the amount is less than 0.3 mass%, the function of dissociating hydrogen molecules into hydrogen cannot be effectively exhibited, and if it exceeds 30.0 mass%, not only the effect is saturated, but also the cost increases.
[0019]
A metal having a function of dissociating a hydrogen molecule into a hydrogen atom as a catalyst component is preferably supported on a finely pulverized carbonaceous material. If a metal serving as a catalyst component is supported before the carbonaceous material is finely pulverized, the carbonaceous material will cover the metal surface thickly when the carbon is finely pulverized, but the function as a catalyst is not effectively exhibited. By supporting the metal serving as a catalyst component on the carbonaceous material after pulverization, the metal surface is not sufficiently coated with the carbonaceous material, and the metal sufficiently comes into contact with hydrogen to exhibit the catalytic function effectively. Can be. That is, hydrogen can sufficiently contact the metal surface as a catalyst component, where hydrogen molecules dissociate into hydrogen atoms and are stored as hydrogen atoms in the carbonaceous material, thereby lowering the hydrogen molecule hydrogen release temperature. And the amount of hydrogen stored can be increased. When graphite was used as the carbonaceous material, the hydrogen gas pressure was 1 MPa, and when no catalyst component was used, the hydrogen release start temperature was about 300 to 320 ° C. and the hydrogen storage amount was about 3 mass%. When the catalyst component is supported on the substrate, the hydrogen release start temperature: about 200 ° C. and the hydrogen storage amount: about 3.5 to 5.0 mass% are remarkably improved. Of course, even if the catalyst component is supported before the pulverization, the effect is seen more than when the catalyst component is not used. The hydrogen release start temperature: about 270 to 290 ° C., and the hydrogen storage amount: 3.0 to 3.5 mass% About.
[0020]
The pressure of the hydrogen gas at the time of grinding the carbonaceous material is preferably 1 MPa or less. If it exceeds 1 MPa, the burden on the equipment will increase. The hydrogen storage material of the present invention can exhibit a sufficiently high hydrogen storage capacity even at 1 MPa or less. The temperature at which the carbonaceous material is pulverized is preferably from room temperature to about 200 ° C. Since the hydrogen storage material of the present invention can release hydrogen at about 200 ° C., the temperature at the time of storage is preferably lower than that. The hydrogen storage material of the present invention has an advantage of having a sufficiently high hydrogen storage capacity even at room temperature.
[0021]
As described above, mechanical pulverization is performed to destroy the crystal structure of the carbonaceous material and store hydrogen on the surface and inside of the finely-divided carbonaceous material. Those having a strong pulverizing ability, such as a planetary ball mill, a rod mill, and a vibrating ball mill, are preferable. Further, since the pulverization of the carbonaceous material is performed in a hydrogen atmosphere, it is preferable to select a material into which hydrogen gas can be easily introduced.
[0022]
【Example】
Hereinafter, examples of the present invention will be described in comparison with comparative examples.
[0023]
[Examples 1 to 10]
1. 1.3 g of finely divided graphite prepared graphite powder (manufactured by Kishida Chemical Co., Ltd., artificial graphite, average particle size: 36 μm) was placed in a 250 cc zirconia mill container, and after evacuation of the inside of the mill container, hydrogen gas was introduced at 1.0 MPa. The milling container was milled for a predetermined time at room temperature using a planetary ball mill. Note that a zirconia ball having almost the same composition and hardness as the container was used as the ball. Milling samples were removed in an argon atmosphere glove box, transferred to a sample bottle under an argon atmosphere, and stored in the same glove box to minimize the effects of oxidation and moisture adsorption.
[0024]
2. 10.0 g of the catalyst-supported atomized graphite was immersed in a minimum amount of water in a beaker and stirred. A predetermined amount of the compound shown in Table 1 was dissolved in a small amount of water so that the metal serving as a catalyst became the ratio shown in Table 1 with respect to the atomized graphite, and the mixture was slowly dropped with a dropping funnel. The entire solution was transferred to an eggplant flask for an evaporator, and heated at 60 ° C. for 2 hours in a water bath while rotating to sufficiently impregnate the solution. After allowing the solution to cool, the evaporator was rotated and reduced in pressure to remove water. Thereafter, the graphite impregnated with the catalyst was scraped out of the eggplant flask, charged in a dryer, and dried at 100 ° C. It was charged into a flow system, slowly heated to 400 ° C. in a nitrogen stream, and thermally decomposed for 4 hours. After returning to room temperature, the mixture was slowly heated again to 450 ° C. in a hydrogen stream and kept for 5 hours. Thereafter, the atmosphere was switched to a nitrogen stream, and the temperature was returned to room temperature. Prior to removal, passivation was performed in a nitrogen stream containing 1% oxygen.
[0025]
3. Measurement of hydrogen storage amount 500 mg of atomized graphite supporting a predetermined catalyst metal was charged into a 50 cc capacity gas container. The inside of the container was evacuated to a predetermined temperature. Thereafter, hydrogen was introduced under 1 MPa and 6 MPa, and the hydrogen storage amount was calculated from the introduced hydrogen pressure and the reduced pressure amount.
[0026]
4. Measurement of hydrogen release start temperature At each pressure, atomized graphite supporting a predetermined catalyst metal was heated in an electric furnace from room temperature to 900 ° C. at a rate of 10 ° C./min, and the amount of released hydrogen was determined by a volumetric method. Further, a hydrogen release curve was created from the TG-MASS measurement, and the hydrogen release start temperature was determined.
[0027]
(Examples 11 to 17)
1. The catalyst-carrying and graphite-refined graphite powder 10.0 g (artificial graphite manufactured by Kishida Chemical Co., Ltd., average particle size 36 μm) was immersed in a minimum amount of water in a beaker and stirred. A predetermined amount of the compound shown in Table 1 was dissolved in a small amount of water so that the metal serving as a catalyst became the ratio shown in Table 1 with respect to the atomized graphite, and the mixture was slowly dropped with a dropping funnel. The entire solution was transferred to an eggplant flask for an evaporator, and heated at 60 ° C. for 2 hours in a water bath while rotating to sufficiently impregnate the solution. After allowing the solution to cool, the evaporator was rotated and reduced in pressure to remove water. After removing the water, it was scraped out from the eggplant flask and dried at 100 ° C. in a dryer. It was charged into a flow system, slowly heated to 400 ° C. in a nitrogen stream, and thermally decomposed for 4 hours. After returning to room temperature, the mixture was slowly heated again to 450 ° C. in a hydrogen stream and kept for 5 hours. Thereafter, the atmosphere was switched to a nitrogen stream, and the temperature was returned to room temperature. Prior to removal, passivation was performed in a nitrogen stream containing 1% oxygen.
[0028]
1.3 g of the graphite powder supporting the catalyst was placed in a 250 mL zirconia mill container, and after evacuation of the inside of the mill container, 1.0 MPa of hydrogen gas was introduced. The milling container was milled for a predetermined time at room temperature using a planetary ball mill. Note that a zirconia ball having almost the same composition and hardness as the container was used as the ball.
[0029]
2. Hydrogen storage amount measurement 500 mg of atomized graphite was charged into a 50-mL capacity gas container. After the inside of the container was evacuated, the temperature was raised to 900 ° C., and then the inside of the container was evacuated to a predetermined temperature as in Example 1. Thereafter, hydrogen was introduced under each pressure, and the hydrogen storage amount was calculated from the introduced hydrogen pressure and the reduced pressure amount.
[0030]
3. Measurement of hydrogen release start temperature As in Examples 1 to 10, atomized graphite supporting a predetermined catalytic metal at each pressure was heated in an electric furnace from room temperature to 900 ° C. at a rate of 10 ° C./min. The amount of released hydrogen was determined. Further, a hydrogen release curve was created from the TG-MASS measurement, and the hydrogen release start temperature was determined.
[0031]
(Comparative Example 1)
1. Atomized graphite preparation 1.3 g of graphite powder (artificial graphite manufactured by Kishida Chemical Co., Ltd., average particle size: 36 μm) was placed in a 250 mL zirconia mill container, and after evacuation of the inside of the mill container, hydrogen gas was introduced at 1.0 MPa. The milling container was milled for a predetermined time at room temperature using a planetary ball mill. Note that a zirconia ball having almost the same composition and hardness as the container was used as the ball.
[0032]
2. As in the case of the hydrogen storage amount measurement examples 11 to 17, 500 mg of atomized graphite was charged into a 50-mL capacity gas container. After the inside of the container was evacuated, the temperature was raised to 900 ° C., and then the inside of the container was evacuated to a predetermined temperature as in Example 1. Thereafter, hydrogen was introduced under each pressure, and the hydrogen storage amount was calculated from the introduced hydrogen pressure and the reduced pressure amount.
[0033]
3. Measurement of hydrogen release start temperature As in Examples 1 to 10, atomized graphite supporting a predetermined catalytic metal at each pressure was heated in an electric furnace from room temperature to 900 ° C. at a rate of 10 ° C./min. The amount of released hydrogen was determined. Further, a hydrogen release curve was created from the TG-MASS measurement, and the hydrogen release start temperature was determined.
[0034]
Table 1 also shows the measurement results of the hydrogen storage amounts and the hydrogen release start temperature of Examples 1 to 17 and Comparative Example 1. FIG. 1 shows hydrogen release curves of Example 3, Example 12, and Comparative Example 1 as examples of hydrogen release curves. The temperature at the first rise of the hydrogen release curve shown in FIG. 1 is the hydrogen release start temperature. The peak around 650 ° C. indicates that hydrogen covalently bonded to carbon was released. FIG. 1 also shows the integrated value of the amount of released hydrogen by the capacity method. In Table 1, the integrated value of the amount of released hydrogen up to 900 ° C. is shown as the amount of stored hydrogen.
[0035]
[Table 1]

[0036]
As shown in Table 1 and FIG. 1, Examples 1 to 17 in which the catalyst was supported were able to sufficiently store hydrogen even at ordinary temperature and constant pressure, and the hydrogen release was higher than Comparative Example 1 in which the catalyst was not supported. It was confirmed that the starting temperature was lowered and the hydrogen storage amount was also increased.
[0037]
In Examples 11 to 17, in which the catalyst was supported before the graphite was refined, the hydrogen release start temperature was 270 to 290 ° C, and the hydrogen storage amount was 2.88 to 3.65 mass% at a pressure of 1 MPa. From 3.52 to 4.27 mass% at 6 MPa, from the hydrogen release start temperature of Comparative Example 1 at 315 ° C., from 2.87 to 3.30 mass% at 1 MPa of hydrogen storage, and from 3.46 to 3.89 mass% at 6 MPa. On the other hand, Examples 1 to 10 in which the catalyst was supported after the graphite was refined had a hydrogen release start temperature of 200 to 214 ° C. and a hydrogen storage amount of 1.27 to 5.27 when the hydrogen storage amount was 1 MPa. It was 3.93 to 6.00 mass% at 09 mass% and 6 MPa, and it was confirmed that the hydrogen release temperature and the hydrogen storage amount were significantly improved.
[0038]
Among the catalyst species used in the experiment, the effects of Examples 9 and 10 using Pd were high, and the hydrogen release start temperature was 200 ° C., the hydrogen storage amount was about 4.6 to 5.1 mass% at 1 MPa, and the hydrogen release amount was about 6 to 5.1 mass%. It was about 5.5 to 6.0 mass%.
[0039]
【The invention's effect】
As described above, according to the present invention, a carbonaceous material finely divided by mechanical pulverization under a hydrogen gas atmosphere as a hydrogen storage material and a metal as a catalyst having a function of dissociating hydrogen molecules into hydrogen atoms are used. Since the hydrogen storage material is used, a large amount of hydrogen can be stably stored even at normal temperature and low pressure, and the hydrogen release temperature can be lowered. In addition, by supporting a metal having a function of dissociating hydrogen molecules into hydrogen atoms after the carbonaceous material is refined rather than before the refinement, the effect of lowering the hydrogen release temperature can be further improved, and The storage amount can be further increased.
[Brief description of the drawings]
FIG. 1 is a diagram showing a hydrogen release curve and an integrated value of a hydrogen storage amount in Examples and Comparative Examples.

Claims (7)

A hydrogen storage material comprising: a carbonaceous material finely divided by mechanical pulverization in a hydrogen gas atmosphere; and a metal having a function of dissociating hydrogen molecules into hydrogen atoms. A hydrogen storage material comprising: a metal having a function of dissociating hydrogen molecules into hydrogen atoms is supported on a carbonaceous material finely divided by mechanical pulverization in a hydrogen gas atmosphere. 3. The hydrogen storage material according to claim 2, wherein hydrogen is stored on a surface and / or inside of the miniaturized carbonaceous material. 4. The metal is Mn, Fe, Co, Ni, Pt, Pd, Rh, Li, B, Na, Mg, K, Ir, Nd, La, Ca, V, Ti, Cr, Cu, Zn, Al, Si, The hydrogen storage material according to any one of claims 1 to 3, wherein the hydrogen storage material is one or more selected from Ru and Ag, or a hydrogen storage alloy. The content of a metal having a function of dissociating the hydrogen molecule into a hydrogen atom with respect to the carbonaceous material is 0.3 to 30.0 mass%, according to any one of claims 1 to 4, wherein The hydrogen storage material as described in the above. A step of mechanically pulverizing the carbonaceous material in a hydrogen gas atmosphere, and a step of supporting a metal having a function of dissociating hydrogen molecules into hydrogen atoms on the carbonaceous material finely divided by mechanical pulverization, A method for producing a hydrogen storage material, comprising storing hydrogen on the surface and / or inside of a carbonaceous material in the course of mechanical pulverization of the carbonaceous material. The method for producing a hydrogen storage material according to claim 6, wherein the pressure of the hydrogen gas is 1 MPa or less.

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