High softening point pitches produced by air-blowing of Qi-free coal-tar derived precursors

• Autorzy: Machnikowski J. , Gerus-Piasecka I. , Kubica K. , Machnikowska H.
• Języki publikacji: EN

Abstrakty

EN

Modified pitches with the softening point of about 220°C were prepared by air-blowing at 300°C of Qi-free pitches from commercial "light" and "heavy" coke-oven tars. The effect of parent tar nature and Qi-free tar distillation conditions on air-blowing behaviour was studied using solvent and extrographic fractionation, elemental analysis, 1H NMR, and contact angle measurement. The kinetics and the mechanism of the mesophase formation on isothermal treatment at 450°C and the optical texture of semi-cokes were studied by polarized-light optical microscopy. Under these conditions totally isotropic pitches of considerably enhanced coking yield and TI content with very little change in elemental composition produced. The air-blowing accelerated the formation of mesophase on carbonization without marked affecting the mesophase units growth and the flow type optical texture of semicoke. The pitch from Qi-free "heavy" tar distilled under the reduced pressure was selected as most suitable potential precursor for isotropic carbon fibers.

Słowa kluczowe

EN

Qi-free pitch; mild oxidation; chemical structure; optical texture

PL

utlenianie; struktura chemiczna; karbonatyzacja; tekstura optyczna

• Wydawca: West Pomeranian University of Technology. Publishing House
• Czasopismo: Polish Journal of Chemical Technology
• Rocznik: 2001
• Tom: Vol. 3, nr 2
• Strony: 11--16
• Opis fizyczny: Bibliogr. 16 poz., tab., rys.

Twórcy

autor

Machnikowski J.

• Institute of Chemistry and Technology of Petroleum and Coal, Wroclaw University of Technology, Gdańska 7/9, 50-344 Wrocław, Poland

autor

Gerus-Piasecka I.

• Institute of Chemistry and Technology of Petroleum and Coal, Wroclaw University of Technology, Gdańska 7/9, 50-344 Wrocław, Poland

autor

Kubica K.

• Institute for Chemical Processing of Coal, Zamkowa 1, 41-803 Zabrze, Poland

autor

Machnikowska H.

• Institute of Chemistry and Technology of Petroleum and Coal, Wroclaw University of Technology, Gdańska 7/9, 50-344 Wrocław, Poland

Bibliografia

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