JP2659077B2 - Manufacturing method of ferromagnetic carbon material - Google Patents
Manufacturing method of ferromagnetic carbon materialInfo
- Publication number
- JP2659077B2 JP2659077B2 JP3109779A JP10977991A JP2659077B2 JP 2659077 B2 JP2659077 B2 JP 2659077B2 JP 3109779 A JP3109779 A JP 3109779A JP 10977991 A JP10977991 A JP 10977991A JP 2659077 B2 JP2659077 B2 JP 2659077B2
- Authority
- JP
- Japan
- Prior art keywords
- carbide
- halogen
- carbon material
- ferromagnetic
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y25/00—Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/0036—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties showing low dimensional magnetism, i.e. spin rearrangements due to a restriction of dimensions, e.g. showing giant magnetoresistivity
- H01F1/0045—Zero dimensional, e.g. nanoparticles, soft nanoparticles for medical/biological use
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Nanotechnology (AREA)
- Crystallography & Structural Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biomedical Technology (AREA)
- General Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Power Engineering (AREA)
- Carbon And Carbon Compounds (AREA)
- Hard Magnetic Materials (AREA)
Description
【0001】本発明は、遷移金属元素を全く含まず炭素
質100%からなる強磁性炭素材料の製造方法の製造方
法に関するものである。The present invention relates to a method for producing a ferromagnetic carbon material containing 100% carbonaceous material without containing any transition metal element.
【0002】[0002]
【従来の技術】これまで、強磁性材料としては、鉄、コ
バルト、ニッケル、などの遷移金属の単体、合金、酸化
物などが用いられてきている。これらの強磁性材料は磁
化率が大きく、保磁力及び残留磁化値が大きいなど、磁
性材料として多くの長所を有する反面、幾つかの短所を
有する。その(1)は、重金属元素であるために比重が
大きく宇宙空間などへ運搬するためには不都合である。
その(2)は、鉄以外の元素は、地球上に資源として偏
在するため、将来的に資源の枯渇が心配されることであ
る。その(3)は、金属元素であるため、硬度が大き
く、軟質な材料とはなりにくいことである。その(4)
は、不要になった場合に、消磁して処分したい場合があ
るが、多大のエネルギーを要することである。2. Description of the Related Art Conventionally, transition metals such as iron, cobalt, nickel and the like, alloys, oxides and the like have been used as ferromagnetic materials. These ferromagnetic materials have many advantages as magnetic materials, such as a high magnetic susceptibility, a large coercive force and a large residual magnetization value, but have some disadvantages. The method (1) is inconvenient for being transported to outer space or the like because of its high specific gravity because it is a heavy metal element.
The second problem is that elements other than iron are unevenly distributed as resources on the earth, and there is a concern that resources will be depleted in the future. The reason (3) is that since it is a metal element, it has high hardness and is unlikely to be a soft material. (4)
In some cases, when it is no longer needed, it is desired to demagnetize and dispose, but this requires a large amount of energy.
【0003】[0003]
【発明が解決使用とする課題】従来の強磁性炭素材料の
有する欠点を克服した材料、言い換えると、従来の強磁
性炭素材料と相補的に使える強磁性炭素材料は、上記に
述べたように、(1)比重が小さく、(2)資源的に豊
富であり、(3)非金属元素であり、(4)簡単に焼却
処分ができる、等の性質を有するものである。このよう
な材料の候補の一つとしては炭素材料がある。従って、
本発明は強磁性を付与した炭素材料の有利な製造方法を
提供することを課題とする。A material that overcomes the drawbacks of the conventional ferromagnetic carbon material, in other words, a ferromagnetic carbon material that can be used complementarily to the conventional ferromagnetic carbon material, as described above, It has properties such as (1) low specific gravity, (2) abundant in resources, (3) non-metallic elements, and (4) easy incineration disposal. One such material candidate is a carbon material. Therefore,
It is an object of the present invention to provide an advantageous method for producing a ferromagnetic carbon material.
【0004】[0004]
【課題を解決するための手段】本発明者は、前記課題を
解決すべく鋭意研究した結果、炭素含量100%の未グ
ラファイト化炭化物が強磁性を示すことを見出し本発明
を完成するに至った。すなわち、本発明によれば、有機
物質の未グラファイト化炭化物をハロゲン又はハロゲン
発生剤の存在下、250〜800℃の温度で加熱処理
し、炭素質100%の未グラファイト化炭化物を得るこ
とを特徴とする強磁性炭素材料の製造方法が提供され
る。また、本発明によれば、有機物質を、ハロゲン又は
ハロゲン発生剤の存在下、250〜800℃の温度で加
熱処理し、炭素質100%の未グラファイト化炭化物を
得ることを特徴とする強磁性炭素材料の製造方法が提供
される。Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that ungraphitized carbide having a carbon content of 100% exhibits ferromagnetism, and have completed the present invention. . That is, according to the present invention, an ungraphitized carbide of an organic substance is heated at a temperature of 250 to 800 ° C. in the presence of a halogen or a halogen generator to obtain 100% carbonaceous ungraphitized carbide. The method for producing a ferromagnetic carbon material described above is provided. According to the present invention, an organic substance is heat-treated at a temperature of 250 to 800 ° C. in the presence of a halogen or a halogen generator to obtain a 100% carbonaceous ungraphitized carbide. A method for producing a carbon material is provided.
【0005】本発明において、強磁性炭素材料を得るに
は、図1からわかるように、未グラフィト化炭化物にお
いて、それに含まれる水素原子を、炭化物のグラファイ
ト化を回避させながら、微底的に除去することが必要で
ある。また、図1からわかるように、炭素原子の電子軌
道がsp2型の平面構造を取っているので、飽和炭化水
素型化合物を利用する場合には、sp3型の四面体構造
からsp2型への転移が起こらなければならない。従っ
て、炭素原子がいわば『寝返りを打つ』運動性を与えな
ければいけない。このような運動性を与えるには加熱処
理が使用される。本発明においては、生成する炭化物の
グラファイト化を回避させるとともに、水素原子を含ま
ない炭素質100%の未グラファイト化炭化物を得るた
めに、炭化物又は有機物質を、ハロゲン又はハロゲン発
生剤の存在下、250〜800℃、好ましくは400〜
600℃の温度で加熱処理する。In the present invention, in order to obtain a ferromagnetic carbon material, as can be seen from FIG. 1, hydrogen atoms contained in an ungraphitized carbide are finely removed while avoiding graphitization of the carbide. It is necessary to. Also, as can be seen from FIG. 1, since the electron orbit of the carbon atom has an sp2 type planar structure, when a saturated hydrocarbon type compound is used, the transition from the sp3 type tetrahedral structure to the sp2 type is made. Must happen. Therefore, the carbon atoms must give a "turn-over" mobility. Heat treatment is used to provide such mobility. In the present invention, in order to avoid graphitization of the generated carbide and to obtain a 100% non-graphitized carbonaceous carbonaceous material containing no hydrogen atom, the carbide or organic substance is converted into a non-graphitized carbide in the presence of a halogen or a halogen generator. 250-800 ° C, preferably 400-
Heat treatment at a temperature of 600 ° C.
【0006】有機物質の加熱処理によって得られる従来
の炭化物には、水素原子が含有されているが、このよう
な炭化物は強磁性を示さない。しかし、ハロゲン又はハ
ロゲン発生剤の存在下で加熱処理を行うと、水素原子
は、炭素に結合するよりも、ハロゲンと結合した方がよ
り安定化するので、炭化物中の水素はハロゲンと反応し
て炭化物中から除去され、炭素質100%の炭化物を得
ることができる。また、加熱処理温度を800℃を超え
ないようにコントロールすることで、炭化物のグラファ
イト化を制止し、SP2−シグマ不対電子を有する強磁
性を示す炭素原子を生成させることができる。Conventional carbides obtained by heat treatment of organic substances contain hydrogen atoms, but such carbides do not show ferromagnetism. However, when heat treatment is performed in the presence of a halogen or a halogen generator, the hydrogen atoms are more stabilized when bonded to halogen than when bonded to carbon, so that hydrogen in the carbide reacts with halogen. It is removed from the carbide to obtain 100% carbonaceous carbide. Further, by controlling the heat treatment temperature so as not to exceed 800 ° C., it is possible to suppress the graphitization of the carbide and generate a ferromagnetic carbon atom having SP2-sigma unpaired electrons.
【0007】本発明により強磁性炭素材料を得る方法と
しては、有機物質を加熱処理してあらかじめ炭化物とし
た後、この炭化物をハロゲン又はハロゲン発生剤の存在
下で加熱処理する方法を好ましく採用し得るが、有機物
質をハロゲン又はハロゲン発生剤の存在下で直接加熱処
理して強磁性炭素材料を得る方法も採用することができ
る。有機物質を加熱処理することにより、炭化物が生成
されることは周知である。有機物質としては、各種のも
のが用いられるが、その取扱いの容易さから、常温で固
体状のものが好ましい。また、高い炭化物収率を与える
点からは、炭素含有率の高い有機物質の使用が好まし
い。有機物質の具体例を示すと、例えば、石油や石炭系
の各種ピッチ類;ポリエチレン、ポリプロピレン、ポリ
塩化ビニル、ポリ塩化ビニリデン、ポリアクリレート、
ポリメタクリレート等の有機高分子物質;パルプ粉末、
木粉等の木質材料等が挙げられる。有機物質は、炭素原
子及び水素原子の他、酸素原子や、窒素原子、イオウ原
子、アルカリ金属原子を含んでいてもよいが、ケイ素原
子や金属原子は、炭化物中に残留してくるので、これら
の原子はできる限り含まないのが好ましく、その炭化物
中の含有量は、10重量%以下、好ましくはゼロ%に保
持する。As a method for obtaining a ferromagnetic carbon material according to the present invention, a method in which an organic substance is heat-treated to form a carbide in advance and then this carbide is heat-treated in the presence of a halogen or a halogen generator can be preferably employed. However, a method in which an organic substance is directly heat-treated in the presence of a halogen or a halogen generator to obtain a ferromagnetic carbon material can also be employed. It is well known that heat treatment of an organic substance produces carbide. As the organic substance, various substances are used, but a solid substance at room temperature is preferable because of its easy handling. From the viewpoint of providing a high carbide yield, it is preferable to use an organic substance having a high carbon content. Specific examples of organic substances include, for example, petroleum and coal-based pitches; polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyacrylate,
Organic polymer substances such as polymethacrylate; pulp powder,
And woody materials such as wood flour. The organic substance may contain an oxygen atom, a nitrogen atom, a sulfur atom, and an alkali metal atom in addition to the carbon atom and the hydrogen atom, but the silicon atom and the metal atom remain in the carbide. Is preferably not contained as much as possible, and its content in the carbide is kept at 10% by weight or less, preferably at 0%.
【0008】ハロゲンとしては、通常、塩素又は臭素が
用いられ、また、ハロゲン発生剤としては、加熱条件で
ハロゲンを生成する物質、例えば、四塩化炭素や各種の
ハロゲン化炭化水素が用いられる。加熱雰囲気は、ハロ
ゲン又はハロゲン発生剤雰囲気の他、これらを含む不活
性ガス(N2やCO2、アルゴンガス等)であることが
できる。ハロゲン又はハロゲン発生剤を含む不活性ガス
雰囲気の場合、そのハロゲン又はハロゲン発生剤の含有
量は、1〜5vol%である。また、雰囲気中の酸素濃
度は0.1xol%以下、好ましくはゼロ%である。雰
囲気圧力は、常圧、加圧及び減圧のいずれでもよいが、
有機物質がガス化や昇華しやすいものの場合、加圧を採
用するのがよい。As the halogen, chlorine or bromine is usually used, and as the halogen generator, a substance which generates a halogen under heating conditions, for example, carbon tetrachloride or various halogenated hydrocarbons is used. The heating atmosphere can be an inert gas (N 2 , CO 2 , argon gas or the like) containing these in addition to a halogen or halogen generator atmosphere. In the case of an inert gas atmosphere containing a halogen or a halogen generator, the content of the halogen or the halogen generator is 1 to 5 vol%. Further, the oxygen concentration in the atmosphere is 0.1 xol% or less, preferably 0%. Atmospheric pressure may be any of normal pressure, pressurization and decompression,
When the organic substance is easily gasified or sublimated, pressurization is preferably used.
【0009】本発明は強磁性を付与した炭素材料を簡単
な方法でしかも効率的に製造することができる。そして
本発明方法で得られる強磁性材料は、上記に述べたよう
に、(1)比重が小さく、(2)資源的に豊富であ
り、、(3)非金属元素であり、(4)簡単に焼却処分
ができる、等の従来の強磁性材料にはない優れた利点を
有するものである。According to the present invention, a carbon material having ferromagnetism can be efficiently produced by a simple method. As described above, the ferromagnetic material obtained by the method of the present invention is (1) low in specific gravity, (2) abundant in resources, (3) a nonmetallic element, and (4) simple It has excellent advantages not available in conventional ferromagnetic materials, such as incineration.
【0010】[0010]
【実施例】次に本発明を実施例によりさらに詳細に説明
する。 実施例1 ポリ塩化ビニル(PVCと略す)2gを取り、図2に示
す管壁に多数の透孔を有する硬質ガラス管に入れて1パ
スカル程度の減圧下で20℃より200℃まで15℃/
分の昇温速度で加熱し、200℃より昇温速度を5℃/
分にして280℃まで加熱する。280℃に60分保持
してから急冷する。冷却後に取り出して秤量すると、
0.346gで収率は17.3%である。次に、このよ
うにして得た炭化物を、図2に示すガラス管に入れ、こ
れを圧力1.33パスカル、空間速度137mの四塩化
炭素気流中に置き、35℃/分の昇温速度で250℃ま
で昇温し、さらに5℃/分で400℃まで昇温する。4
00℃に120分間保持してから急冷する。収量は0.
3gで出発PVC量に対して15.0%である。この炭
化物の磁化率を振動容量法で測定してみると、保磁力
3.82mT,残留磁化1.57×10−3emu/g
を得た。Next, the present invention will be described in more detail with reference to examples. Example 1 2 g of polyvinyl chloride (abbreviated as PVC) was taken, put in a hard glass tube having a large number of through holes in the tube wall shown in FIG. 2, and placed under a reduced pressure of about 1 Pascal from 20 ° C to 200 ° C at 15 ° C /
Heating at a rate of 5 min / min.
Heat to 280 ° C in minutes. Hold at 280 ° C. for 60 minutes, then quench. Take out and weigh after cooling,
The yield is 17.3% at 0.346 g. Next, the carbide thus obtained was placed in a glass tube shown in FIG. 2, placed in a carbon tetrachloride gas stream at a pressure of 1.33 Pascal and a space velocity of 137 m, and heated at a rate of 35 ° C./min. The temperature is raised to 250 ° C. and further to 400 ° C. at 5 ° C./min. 4
Hold at 00 ° C for 120 minutes, then quench. The yield is 0.
In 3 g, it is 15.0% based on the starting PVC amount. When the magnetic susceptibility of this carbide is measured by the vibration capacitance method, the coercive force is 3.82 mT, and the residual magnetization is 1.57 × 10 −3 emu / g.
I got
【0011】[0011]
【実施例2】PVC2gを取り、図2に示すガラス管に
入れて四塩化炭素気流中で加熱する。四塩化炭素の圧力
は1.33パスカル、その空間速度137mである。2
0℃より200℃まで15℃/分の昇温速度で加熱し、
200℃より昇温速度を5℃/分にして280℃まで加
熱する。280℃に60分保持してから急冷する。冷却
後に取り出して秤量すると0.328gで収率16.4
%である。このようにして得た炭化物を再び図2のガラ
ス管に移して、上記と同じ四塩化炭素気流中で同一流速
で加熱処理を行った。35℃/分で250℃まで昇温
し、次いで5℃/分で400℃まで昇温する。400℃
に120分間保持してから急冷する。収量は0.266
gで、収率13.3%である。この炭化物の磁化率を測
定してみると、保磁力3.78mT,残留磁化3.60
×10−3emu/gを得た。Example 2 2 g of PVC was placed in a glass tube shown in FIG. 2 and heated in a stream of carbon tetrachloride. The pressure of carbon tetrachloride is 1.33 Pascal and its space velocity is 137 m. 2
Heating from 0 ° C to 200 ° C at a rate of 15 ° C / min,
Heating from 200 ° C. to 280 ° C. at a rate of 5 ° C./min. Hold at 280 ° C. for 60 minutes, then quench. After cooling, it was taken out and weighed, yielding 0.328 g in a yield of 16.4.
%. The carbide thus obtained was transferred again to the glass tube of FIG. 2 and subjected to a heat treatment at the same flow rate in the same carbon tetrachloride gas stream as described above. The temperature is raised to 250 ° C. at 35 ° C./min and then to 400 ° C. at 5 ° C./min. 400 ° C
And then quench. Yield 0.266
g in a yield of 13.3%. When the magnetic susceptibility of this carbide was measured, the coercive force was 3.78 mT and the residual magnetization was 3.60.
× 10 −3 emu / g was obtained.
【0012】実施例3 実施例2で作成した強磁性炭素材料をさらに品質改良す
る目的で、四塩化炭素気流中で再度熱処理した。加熱容
器は図2のものを使用した。再処理温度は400℃から
800℃までとし、四塩化炭素の圧力は1.33Pa、
線速度は137m/分である。20℃から300℃まで
は昇温速度20℃/分で加熱し、300℃より最終到達
温度の50℃下までは5℃/分の昇温速度で加熱し、そ
の温度から最終到達温度までは1℃/分で昇温した。最
終加熱温度に到達したら、その温度に100分間保持し
てから急冷して室温まで冷却した。このようにして得
た、再熱処理ずみ強磁性炭素材料の収率は、使用した一
次処理原料に対して約77〜90%であった。このよう
に再熱処理した炭素材料について、磁化率の測定を行
い、得られた保磁力、残留磁化を再熱処理温度に対して
プロットした結果を図3に示す。図3で最も残留磁化の
大きい500℃処理物から得られる磁化率のヒステリシ
ス曲線を図4に示す。Example 3 The ferromagnetic carbon material prepared in Example 2 was heat-treated again in a stream of carbon tetrachloride in order to further improve the quality. The heating container shown in FIG. 2 was used. The reprocessing temperature is from 400 ° C. to 800 ° C., the pressure of carbon tetrachloride is 1.33 Pa,
The linear velocity is 137 m / min. From 20 ° C to 300 ° C, heat at a heating rate of 20 ° C / min. From 300 ° C to 50 ° C below the ultimate temperature, heat at a heating rate of 5 ° C / min. The temperature was raised at 1 ° C./min. When the final heating temperature was reached, the temperature was maintained for 100 minutes and then rapidly cooled to room temperature. The yield of the reheat-treated ferromagnetic carbon material thus obtained was about 77 to 90% based on the primary processing raw material used. The magnetic susceptibility of the re-heat treated carbon material was measured, and the obtained coercive force and residual magnetization were plotted against the re-heat treatment temperature, as shown in FIG. FIG. 4 shows a hysteresis curve of the magnetic susceptibility obtained from the 500 ° C. treated product having the largest residual magnetization in FIG.
【0013】実施例4 木炭2.0gを取り、これを100メッシュ以下に粉砕
し、磁性ボートに入れて、実施例3と同一の条件下(最
終到達加熱温度600℃)で四塩化炭素気流中で加熱処
理を行った。収率は13%であった。このものについて
磁化率を測定して、保磁力0.3mT,残留磁化7.0
×10−4emu/gを得た。Example 4 2.0 g of charcoal was pulverized to 100 mesh or less, placed in a magnetic boat, and placed in a stream of carbon tetrachloride under the same conditions as in Example 3 (final ultimate heating temperature: 600 ° C.). Heat treatment was performed. The yield was 13%. The susceptibility of this sample was measured, and the coercive force was 0.3 mT and the residual magnetization was 7.0.
× 10 -4 emu / g was obtained.
【図1】強磁性炭素材料分子の構造式を示す。FIG. 1 shows a structural formula of a ferromagnetic carbon material molecule.
【図2】炭化反応用硬質ガラス管を示す。FIG. 2 shows a hard glass tube for a carbonization reaction.
【図3】強磁性炭素材料の再熱処理温度による磁性の変
化のグラフを示す。FIG. 3 is a graph showing a change in magnetism of a ferromagnetic carbon material depending on a reheating temperature.
【図4】500℃再熱処理物の磁化率曲線を示す。FIG. 4 shows a magnetic susceptibility curve of a 500 ° C. reheated product.
Claims (2)
ロゲン又はハロゲン発生剤の存在下、250〜800℃
の温度で加熱処理し、炭素質100%の未グラファイト
化炭化物を得ることを特徴とする強磁性炭素材料の製造
方法。An ungraphitized carbide of an organic substance is heated at 250 to 800 ° C. in the presence of a halogen or a halogen generator.
A method for producing a ferromagnetic carbon material, wherein a heat treatment is performed at a temperature of 100% to obtain 100% non-graphitized carbide of carbonaceous material.
剤の存在下、250800℃の温度で加熱処理し、炭素
質100%の未グラファイト化炭化物を得ることを特徴
とする強磁性炭素材料の製造方法。2. A method for producing a ferromagnetic carbon material, comprising heating an organic substance at a temperature of 250800 ° C. in the presence of a halogen or a halogen generator to obtain 100% non-graphitized carbide of carbonaceous material. .
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JP3109779A JP2659077B2 (en) | 1991-04-15 | 1991-04-15 | Manufacturing method of ferromagnetic carbon material |
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JP3109779A JP2659077B2 (en) | 1991-04-15 | 1991-04-15 | Manufacturing method of ferromagnetic carbon material |
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JPH07187630A JPH07187630A (en) | 1995-07-25 |
JP2659077B2 true JP2659077B2 (en) | 1997-09-30 |
Family
ID=14519016
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JP3109779A Expired - Lifetime JP2659077B2 (en) | 1991-04-15 | 1991-04-15 | Manufacturing method of ferromagnetic carbon material |
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JP2007153674A (en) * | 2005-12-06 | 2007-06-21 | Tokyo Institute Of Technology | Method for producing charcoal |
US20090114520A1 (en) * | 2005-12-06 | 2009-05-07 | Tokyo Institute Of Technology | Method of Producing Charcoal |
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JPH02296710A (en) * | 1989-05-10 | 1990-12-07 | Idemitsu Kosan Co Ltd | Production of carbonaceous magnetic material |
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