JPS6315885A - Manufacture of optically isotropic coke - Google Patents
Manufacture of optically isotropic cokeInfo
- Publication number
- JPS6315885A JPS6315885A JP61159331A JP15933186A JPS6315885A JP S6315885 A JPS6315885 A JP S6315885A JP 61159331 A JP61159331 A JP 61159331A JP 15933186 A JP15933186 A JP 15933186A JP S6315885 A JPS6315885 A JP S6315885A
- Authority
- JP
- Japan
- Prior art keywords
- coke
- anhydride
- pitch
- isotropic
- coal tar
- 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.)
- Pending
Links
- 239000000571 coke Substances 0.000 title abstract description 33
- 238000004519 manufacturing process Methods 0.000 title description 6
- 125000003118 aryl group Chemical group 0.000 claims abstract description 10
- 239000011294 coal tar pitch Substances 0.000 claims abstract description 8
- 239000012298 atmosphere Substances 0.000 claims abstract description 7
- 239000011301 petroleum pitch Substances 0.000 claims abstract description 5
- 238000010438 heat treatment Methods 0.000 claims abstract description 4
- 150000008065 acid anhydrides Chemical class 0.000 claims description 7
- 239000003575 carbonaceous material Substances 0.000 abstract description 9
- 238000000034 method Methods 0.000 abstract description 9
- ANSXAPJVJOKRDJ-UHFFFAOYSA-N furo[3,4-f][2]benzofuran-1,3,5,7-tetrone Chemical compound C1=C2C(=O)OC(=O)C2=CC2=C1C(=O)OC2=O ANSXAPJVJOKRDJ-UHFFFAOYSA-N 0.000 abstract description 7
- 239000012299 nitrogen atmosphere Substances 0.000 abstract description 5
- LGRFSURHDFAFJT-UHFFFAOYSA-N Phthalic anhydride Natural products C1=CC=C2C(=O)OC(=O)C2=C1 LGRFSURHDFAFJT-UHFFFAOYSA-N 0.000 abstract description 4
- JHIWVOJDXOSYLW-UHFFFAOYSA-N butyl 2,2-difluorocyclopropane-1-carboxylate Chemical compound CCCCOC(=O)C1CC1(F)F JHIWVOJDXOSYLW-UHFFFAOYSA-N 0.000 abstract description 4
- 150000008064 anhydrides Chemical class 0.000 abstract description 3
- SRPWOOOHEPICQU-UHFFFAOYSA-N trimellitic anhydride Chemical compound OC(=O)C1=CC=C2C(=O)OC(=O)C2=C1 SRPWOOOHEPICQU-UHFFFAOYSA-N 0.000 abstract description 3
- -1 aromatic carboxylic anhydride Chemical class 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 description 12
- 239000002994 raw material Substances 0.000 description 11
- 230000003287 optical effect Effects 0.000 description 9
- 239000011295 pitch Substances 0.000 description 9
- SMWDFEZZVXVKRB-UHFFFAOYSA-N Quinoline Chemical compound N1=CC=CC2=CC=CC=C21 SMWDFEZZVXVKRB-UHFFFAOYSA-N 0.000 description 6
- 238000000465 moulding Methods 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 2
- 238000004581 coalescence Methods 0.000 description 2
- VILAVOFMIJHSJA-UHFFFAOYSA-N dicarbon monoxide Chemical compound [C]=C=O VILAVOFMIJHSJA-UHFFFAOYSA-N 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 1
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 150000001244 carboxylic acid anhydrides Chemical class 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000000269 nucleophilic effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Carbon And Carbon Compounds (AREA)
- Working-Up Tar And Pitch (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、等方性炭素材料の原料としての光学的等方性
コークスの製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing optically isotropic coke as a raw material for an isotropic carbon material.
等方性炭素材料は、放電加工用電極材黒鉛やメカニカル
シール軸受などの機械用カーボン、原子力用カーボン等
の特殊炭素材の原料として利用される。Isotropic carbon materials are used as raw materials for special carbon materials such as graphite for electrode materials for electric discharge machining, carbon for machines such as mechanical seal bearings, and carbon for nuclear power applications.
〈従来技術とその問題点〉
従来、ピッチを原料にして、等方性炭素材料原料となる
コークスを製造すべく熱処理を行なうと、メソフェーズ
と称される一種の液晶が生成し、成長・合体を経てコー
クス化するため、得られるコークスの光学組織は、窯業
協会誌９１（１０）１９８３．４５７にも示される様に
原料性状に応じてモザイク状あるいは流れ状、あるいは
その両者が混合した状態を呈するものの混合物で、光学
的異方性となる。<Prior art and its problems> Conventionally, when pitch is used as a raw material and heat-treated to produce coke, which is a raw material for isotropic carbon materials, a type of liquid crystal called mesophase is generated, which is difficult to grow and coalesce. The optical structure of the resulting coke is mosaic, flow, or a mixture of both, depending on the properties of the raw material, as shown in the Ceramics Association Journal 91 (10) 1983.457. It is a mixture of substances and has optical anisotropy.
従って、従来方法で得られたコークスを用いて、等方性
炭素材を製造するためには、原料コークスを超微粉砕し
、成型時にコークスが一定方向に配向しないよう、例え
ばアイソスタティックプレスを用いることが必要となる
など、その作業性に問題があった。Therefore, in order to produce an isotropic carbon material using coke obtained by conventional methods, the raw material coke is ultra-finely pulverized, and an isostatic press, for example, is used to prevent the coke from being oriented in a fixed direction during molding. There were problems with its workability, such as the need to
〈発明の目的ン
本発明の目的は、光学的等方性コークスの製造方法を提
供し、原料コークスを用いて、等方性炭素材料を製造す
る際に、等方向な圧力を必要としない成型法、例えば通
常のモールｉ・成型法、あるいは押し出し成へ１１法を
用いることが可ｒ１１な原料コークスの製造方法を提供
せんとするものである。<Object of the invention> The object of the present invention is to provide a method for producing optically isotropic coke, and a molding process that does not require isotropic pressure when producing an isotropic carbon material using raw material coke. It is an object of the present invention to provide a method for producing raw material coke, which allows use of a conventional molding method, for example, or an extrusion molding method.
〈発明の構成〉
本発明者らは、原料コークスの光学組織が、流れ状であ
れ、モザイク状であれ、あるいは両者の７１＋ｊ合した
ものであれ、光学的等方＋＋１を示すことか、等方＋’
Ｉ炭素材料を製造する際に、等方向に圧力による成べり
法を必要とする最大の接円であることに着１１シ、ター
ル・ピッチからメソフェーズの生成、成長、合体の過程
を経由Ｊ−ることなく、コークスを製造する方法につい
て幾多の研究を行なった。<Structure of the Invention> The present inventors have discovered that whether the optical structure of the raw material coke is flowing, mosaic, or a combination of both, it exhibits optical isotropy++1 or isotropy. +'
When manufacturing carbon materials, it is the largest tangential circle that requires isodirectional pressure-based forming method. Many studies were conducted on methods of producing coke.
その結果、）１−香族多４ＩＩカルボン酸無水物をビッ
ヂに添加してコークス化すれば、メソフェーズを経由す
る°１ｔなくコークス化し、その結果、光学的等方Ｐ［
コークスがＩＩられる・１を実を（＾い出し、本発明に
至ったものである。As a result, if 1-aromatic poly-4II carboxylic acid anhydride is added to bitge and coked, coke is formed without passing through the mesophase, and as a result, optically isotropic P[
The present invention was achieved by extracting the coke from the coke.
すなわち本発明はコールタールピッチおよび／または石
油ピッチに、芳香族多価カルボン酸無水物を１０ｗｊ％
〜５０Ｗ１％添加し、不活性雰囲気下で２５０°Ｃ〜４
５０℃で熱処理を行なうことを特徴とする光学的等力＋
１コークスの製造方法を提供する。That is, the present invention adds 10 wj% of aromatic polycarboxylic acid anhydride to coal tar pitch and/or petroleum pitch.
~50W 1% added, 250°C under inert atmosphere ~4
Optical isometric + characterized by heat treatment at 50℃
1 provides a method for producing coke.
以ｌ；、本発明について詳細に説明する。Hereinafter, the present invention will be explained in detail.
本発明で用いる原料ピッチは石油系ピッチ、コールター
ルピッチいずれでもよく、またこれらの混合物でもよい
。The raw material pitch used in the present invention may be either petroleum pitch or coal tar pitch, or a mixture thereof.
ピッチに添加する）′Ｊ°香族多価カルボン酸無水物は
、無水ビロメリツ［・酸（Ｃ＋。１１□〔）６）、無水
トリメリッ］・酸（Ｇ９１１．＋０．） 、無水フタル
酸（（：８１１４０３ ）等を代表的に挙げることがで
きる。)'J° Aromatic polycarboxylic acid anhydrides include bilomeric anhydride [・acid (C+.11□[)6), trimellitic anhydride]・acid (G911.+0.), phthalic anhydride (( :811403) and the like are representative examples.
なお、無水フタル酸等の沸点の低い芳香族カルボン酸無
水物を使用するときは、加圧下で熱処理を行うことが望
ましい。Note that when using an aromatic carboxylic acid anhydride with a low boiling point such as phthalic anhydride, it is desirable to perform the heat treatment under pressure.
無水ピロメリット酸
關
無水ｉ・リメリット酸
〇
無水フタル酸
刀香族多価カルボン酸無水物の添加ｌｉｔは、１゜ｗｔ
％〜５０ｗｔ％とするのがよい。１０ｗ１％未満である
と改質の程度が弱く得られるコークスは流れ構造を小し
、５０ｗｔ％超であると経済コスト１−不必要だからで
ある。Addition lit of pyromellitic anhydride, limellitic anhydride, phthalic anhydride, aromatic polycarboxylic acid anhydride is 1゜wt
% to 50 wt%. This is because if the content is less than 10w1%, the degree of reforming is weak and the obtained coke has a small flow structure, and if it is more than 50wt%, the economic cost is 1 - unnecessary.
ビッヂに））−香族多価カルホン酸無水物を１０Ｗ１％
〜３０ｗｔ％添加し、攪拌・混合後、不活＋１：雰囲気
ドで２５０℃〜４５０℃の反応温度で、２時間〜１０時
間の反応を行なうと、メソフェーズの生成・成長・合体
の過程を経由しない不融のコークスを製造することｈ＜
’ｉ＋’（能である。10W1% of aromatic polycarphonic acid anhydride
After adding ~30 wt% and stirring/mixing, the reaction is carried out for 2 to 10 hours at a reaction temperature of 250°C to 450°C in an inert +1 atmosphere, and the process of mesophase generation, growth, and coalescence occurs. To produce unmelted coke that does not
'i+' (Noh.
反応温度が２５０℃未満であると、反応が非常にＨく実
買上不可能であり、４５０℃超であると、装置トの制約
があるからである。If the reaction temperature is less than 250°C, the reaction will be too hot to be commercially available, and if it is more than 450°C, there will be restrictions on the equipment.
不活性雰囲気下で反応を行うのは酸化を防ぐためであり
、Ｎ２雰囲気、アルゴンガス雰囲気が好ましい。The reason for conducting the reaction under an inert atmosphere is to prevent oxidation, and N2 atmosphere or argon gas atmosphere is preferable.
反応温度及び反応時間の組み合わせは、芳香族多価カル
ボン酸無水物の添加ｊ７１にもよるが、例えば、ピッチ
に対して３０％添加した場合には、３５０℃以１４５０
℃以トーの反応温度では、コークス化させるために２〜
６時間必要とし、２５０℃以１゛３５０℃以下の反応温
度では、６時間風１″１０時間以下の反応時間を必要と
する。The combination of reaction temperature and reaction time depends on the addition of the aromatic polycarboxylic acid anhydride, but for example, when adding 30% to the pitch,
At reaction temperatures below ℃, 2~
At a reaction temperature of 250° C. to 1 to 350° C., the reaction time is 10 hours or less.
本発明方法により、ピッチから光学的等方性コークスを
製造することが可能である。With the method of the invention it is possible to produce optically isotropic coke from pitch.
芳香族カルボン酸とピッチの炭化反応機構はまたよくわ
かっていないが、次の様であると考えられる。Although the carbonization reaction mechanism between aromatic carboxylic acids and pitch is not well understood, it is thought to be as follows.
例えば芳香族多価カルボン酸無水物としてＰＭＯＡ（無
水ピロメリット酸）を用いると、ＰＭＤＡのカルホニル
炭素とピッチのＮとの弱い結合すなわち電荷移動がおこ
る。これはＮのローンベア電子のカルホニル炭素への求
核的なアタックと考えてもよい。For example, when PMOA (pyromellitic anhydride) is used as the aromatic polycarboxylic acid anhydride, a weak bond between the carbonyl carbon of PMDA and N of the pitch, that is, charge transfer occurs. This can be considered as a nucleophilic attack of the lone bare electron of N on the carbonyl carbon.
この結合によりＰＭＤへの沸点が上昇し、カルボニル基
と芳香族環の間の開裂が熱的に生じ、芳香族環はカルボ
ニル基を失って最高４コのラジカルサイトを持った芳香
族ラジカルとなり、このラジカルサイトがピッチを攻撃
する。This bond increases the boiling point to PMD, thermally causes cleavage between the carbonyl group and the aromatic ring, and the aromatic ring loses its carbonyl group to become an aromatic radical with up to 4 radical sites. This radical site attacks the pitch.
ラジカルサイトとピッチとの結合がおこり、低温で３次
元架橋が生じる。このためメソフェーズを形成するため
の平坦な分子が生じなくなり、メソフェーズを経ずに固
化（コークス化）する。Bonding between radical sites and pitch occurs, and three-dimensional crosslinking occurs at low temperatures. For this reason, flat molecules for forming a mesophase are no longer produced, and the material solidifies (cokes) without passing through a mesophase.
〈実施例〉 以下に実施例を用いて本発明を具体的に述べる。<Example> The present invention will be specifically described below using Examples.
実施例１
コールタールピッチに対して無水ピロメリット酸（ＣＩ
０１１２０６）を３０ｗｔ％添加し、Ｎ２雰囲気中、４
００℃で２時間反応させた。得られた生成物は不融のコ
ークスであり、キノリンネ溶分は９５％であった。得ら
れたコークスを常法に従って偏光顕微鏡で観察すると全
面が光学的等方性を示し、光学的異方性を示す部分は皆
無であった。Example 1 Pyromellitic anhydride (CI) against coal tar pitch
011206) was added at 30 wt%, and 4% was added in an N2 atmosphere.
The reaction was carried out at 00°C for 2 hours. The obtained product was an infusible coke with a quinoline solubility of 95%. When the obtained coke was observed under a polarizing microscope according to a conventional method, the entire surface showed optical isotropy, and there was no part showing optical anisotropy.
実施例２
コールタールピッチに無水ピロメリット酸を１０ｗｔ％
添加し、Ｎ２雰囲気下、３００℃で８時間の反応を行な
った。得られた生成物は不融のコークスで、キノリンネ
溶分は９０％であった。Example 2 10 wt% pyromellitic anhydride in coal tar pitch
The reaction was carried out at 300° C. for 8 hours under N2 atmosphere. The obtained product was an infusible coke with a quinoline solubility of 90%.
このコークスを常法に従って偏光顕微鏡で観察すると、
全面が光学的等方性であり、光学的異方性部分は皆無で
あった。When this coke is observed using a polarizing microscope according to the conventional method,
The entire surface was optically isotropic, and there were no optically anisotropic parts.
実施例３
コールタールピッチに無水トリメリット酸（Ｃ９１ＬＯ
５）を３０ｗｔ％添加し、Ｎ２雰囲気下、４００℃で２
時間の反応を行なった。得られた生成物は不融のコーク
スで、キノリンネ溶分は９３％であった。このコークス
を常法に従って偏光顕微鏡で観察すると、全面が光学的
等方性であり、光学的異方性部分は皆無であった。Example 3 Trimellitic anhydride (C91LO) added to coal tar pitch
5) was added at 30 wt% and heated at 400°C under N2 atmosphere.
A time reaction was performed. The obtained product was an infusible coke with a quinoline solubility of 93%. When this coke was observed using a polarizing microscope according to a conventional method, it was found that the entire surface was optically isotropic and there were no optically anisotropic parts.
〈発明の効果〉
従来ピッチを原料にしてコークス化を行なうと、メソフ
ェーズの生成、成長合体を経てコークス化するので、得
られるコークスの光学組織は組織上の差はあるものの異
方性を呈するので、等方性炭素材料を成型する場合、一
定方向に粒子が配向するのを防ぐために、等方向な圧力
を要し、通常のモールド成型あるいは押し出し成型を用
いることはできない。<Effects of the Invention> When conventional pitch is used as a raw material to form coke, it is formed into coke through the generation and growth coalescence of mesophase, so the optical structure of the resulting coke exhibits anisotropy, although there are structural differences. When molding an isotropic carbon material, isotropic pressure is required to prevent particles from aligning in a certain direction, and normal molding or extrusion cannot be used.
しかし、本発明方法によれば、得られるコークスは光学
的に全くの等方性を示すので、モールド成型あるいは、
押し出し成型を用いても一定方向には配向することはな
く、作業性の良い実用上非常に有利なコークスを製造で
きる。However, according to the method of the present invention, the coke obtained exhibits complete optical isotropy, so molding or
Even if extrusion molding is used, coke is not oriented in a fixed direction, and coke can be produced that is highly workable and very advantageous in practice.
同 弁理士 石 井 陽 −鞠、；７：
−、−ｒｉ、 、、 、 。Patent attorney Yo Ishii - Mari; 7:
−, −ri, ,, , .
［ｊ：１・１、゛[j:1・1,゛
Claims (1)
、芳香族多価カルボン酸無水物を１０ｗｔ％〜５０ｗｔ
％添加し、不活性雰囲気下で２５０℃〜４５０℃で熱処
理を行なうことを特徴とする光学的等方性コークスの製
造方法。(1) 10wt% to 50wt of aromatic polycarboxylic acid anhydride to coal tar pitch and/or petroleum pitch
% and heat treatment at 250°C to 450°C in an inert atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61159331A JPS6315885A (en) | 1986-07-07 | 1986-07-07 | Manufacture of optically isotropic coke |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61159331A JPS6315885A (en) | 1986-07-07 | 1986-07-07 | Manufacture of optically isotropic coke |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6315885A true JPS6315885A (en) | 1988-01-22 |
Family
ID=15691485
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61159331A Pending JPS6315885A (en) | 1986-07-07 | 1986-07-07 | Manufacture of optically isotropic coke |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6315885A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03290309A (en) * | 1990-04-06 | 1991-12-20 | Nippon Steel Corp | Production of carbonaceous precursor |
| US5121511A (en) * | 1989-11-27 | 1992-06-16 | Matsushita Electric Works, Ltd. | Shower device |
| US5428850A (en) * | 1990-03-12 | 1995-07-04 | Toto Ltd. | Shower apparatus |
| JP2013254728A (en) * | 2012-05-10 | 2013-12-19 | Jfe Chemical Corp | Method for producing negative electrode material for lithium ion secondary battery |
| CN104293366A (en) * | 2014-10-21 | 2015-01-21 | 华侨大学 | Method for preparing isotropic coke through catalytic carbonization |
-
1986
- 1986-07-07 JP JP61159331A patent/JPS6315885A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5121511A (en) * | 1989-11-27 | 1992-06-16 | Matsushita Electric Works, Ltd. | Shower device |
| US5428850A (en) * | 1990-03-12 | 1995-07-04 | Toto Ltd. | Shower apparatus |
| JPH03290309A (en) * | 1990-04-06 | 1991-12-20 | Nippon Steel Corp | Production of carbonaceous precursor |
| JP2013254728A (en) * | 2012-05-10 | 2013-12-19 | Jfe Chemical Corp | Method for producing negative electrode material for lithium ion secondary battery |
| CN104293366A (en) * | 2014-10-21 | 2015-01-21 | 华侨大学 | Method for preparing isotropic coke through catalytic carbonization |
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