• 제목/요약/키워드: Coal-tar

검색결과 119건 처리시간 0.03초

탄소/탄소 복합재 매트릭스 전구체인 이방성 메조페이스 형성을 위한 콜타르 핏치의 열분해 조건 연구 (A study on the Condition of Pyrolysis of Coal Tar Pitch to Form the Mesophase as a Matrix Precursor of Carbon/Carbon Composites)

  • 정형진;정윤중;조동환;임연수;김기원
    • 한국세라믹학회지
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    • 제34권9호
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    • pp.963-968
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    • 1997
  • Coal tar pitch was used to study the effect of the pyrolysis conditions to produce mesophase pitch used as a matrix precursor for carbon/carbon composites. The pyrolysis conditions were presented in all cases that the total pressure was 1 atm and the first stage temperature was changed from 25$0^{\circ}C$ to 34$0^{\circ}C$ to remove the low molecular weight compounds in the pitch, and then, heated to 40$0^{\circ}C$ to form anisotropic mesophase as the second stage temperature. The first stage temperature was very affected to form resulting anisotropic mesophase pitch. The resulting mesophase pitches show a significantly increased anisotropic contents upto 30$0^{\circ}C$. However, the contents of mesophase were decreased above 30$0^{\circ}C$. It was the reason that the first stage temperature had been control the number of free radicals to react the aromatic compounds in the pitch to form high molecular weight compound. Therefore, the two stage pyrolysis method could be very effectively used to control various contents of anisotropic polyaromatic mesophase compared to continuous to continuous heating method.

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The Carbonization Behaviors of Coal Tar Pitch for Mechanical Seal

  • Chae, Jae-Hong;Kim, Kyung-Ja;Cho, Kwang-Youn;Choi, Jae-Young
    • Carbon letters
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    • 제2권3_4호
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    • pp.182-191
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    • 2001
  • Quinoline insoluble formed by the heat treatment was hot-pressed near its softening point. The green body was stabilized in the temperature range of $300{\sim}400^{\circ}C$ and subsequently carbonized below $1300^{\circ}C$ in an argon atmosphere. The behaviors of QI formation was examined with varying the heat treatment temperature and the lapse of time of the sample carbonized at various temperatures. And the mechanical property, corrosion resistance, and friction behavior were also measured optimum content of mesophase pitch ensured a dense structure and high $LC_{(002)}$ value, which resulted in high mechanical properties, good corrosion resistance, and low-stable friction behavior.

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고밀도, 등방성 탄소의 제조에 관한 연구 (Preparation of Isotropic Carbon with High Density)

  • 오종기;이선우;박광원
    • 한국세라믹학회지
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    • 제28권11호
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    • pp.908-916
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    • 1991
  • The characteristics of the carbonized and calcined products made from coal tar pitch coke and coal tar pitch, were investigated in the aspect of the manufacture of isotropic graphite with high density. The mesophase from the pitch was rapidly formed at higher heat-treatment temperature between 410$^{\circ}C$ and 450$^{\circ}C$, where the insolubes in the pitch accelerated the rate of nucleation and growth of the mesophase. The benzene insolubles and the quinoline insolubes were increased as the heat treatment temperature and the heat-treatment time increased. The ratio of benzene insolubles and quinoline solubles (BI/QS) was decreased as the heat-treatment temperature was higher and maintained to be nearly constant regardless of heat-treatment time at fixed heat treatment temperature. The bulk density of the calcined carbon was linearly proportional to the ratio of quinoline solubes to volatile matter in the green coke. Anisotropic ratio of electrical resistance was measured to be between 0.98 and 1.10.

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열처리 피치를 사용한 탄소성형체의 산화안정화 (The Oxi-stabilization of Carbon Precursor Using Heat Treated Pitch)

  • 조광연;김경자
    • 한국세라믹학회지
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    • 제40권10호
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    • pp.985-990
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    • 2003
  • 콜타르 피치를 450∼50$0^{\circ}C$로 가열하여 메조페이스 피치를 제조하였다. 열처리된 피치는 시편의 부풀림과 변형을 줄이기 위해 공기 중 160∼24$0^{\circ}C$로 산화안정화하였다. 고온열처리핏치를 이용한 부피를 가진 성형체의 산화안정화 원리를 조사하기 위해 열중량감소, FT-IR을 측정하였다. 부피를 가진 성형체에 대한 산화안정화의 영향은 쇼아경도, 곡강도를 측정하여 파악하였다.

Preparation of Activated Carbon Fiber from Chemically Modified Coal-tar Pitch

  • Lee, Dong-Jun;Yang, Gap-Seung;Ryu, S.K.;Kim, Y.J.
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 1996년도 추계 학술발표회
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    • pp.117-123
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    • 1996
  • Cabon fiber of general purpose was prepared from coal tar pitch modified with 10% benzoquinine(BQ) at 380C for 3 hours. Such a modified pitch raised the softening of the pitch from 85C to 271C at the yield of 40%. The modified pitch was spun smoothly at a rate of 480m/min into a fiber of 20um diameter. The fiber was stabilized stepwise at 236C (5C/min) and 312C (1C/min) for 3 hours each. Both carbonized and graphitized fibers exhibited tensile strength of 570MPa which appears large enough as a precursor for active carbon fiber. The activated carbon fiber prepared exhibited relatively high surface area of 2062m2/g at 76% burn-off and rather narrow distribution pore size of 20A.

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