Modification of the properties and carbonization behaviour of coal tar pitches on progressive air-blowing

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

Abstrakty

EN

Pitches with softening points of about 140°C, 175°C and 210°C were prepared by progressive air-blowing at 300°C of coal-tar pitches from different commercial coke-oven tars. The modification induced by the mild oxidation was monitored using solvent fractionation, elemental analysis and contact angle measurement. The kinetics and mechanism of mesophase formation on isothermal treatment at 450°C and the optical texture of resultant cokes were studied by polarized-light optical microscopy. The air-blowing increases gradually the coking yield and toluene insoluble content of pitch with very little changes in quinoline insoluble content and elemental composition. The modified pitches preserve characteristic structural features of parent materials. Air-blowing accelerates the formation of mesophase on carbonization and modifies to a different extent the mechanism of the transformation. QI particles tend to form large aggregates in the early stage of the transformation and mesophase growth occurs in the practically Ql-free pitch, leading to two-phase optical texture of resultant cokes.

Słowa kluczowe

EN

coal-tar pitch; mild oxidation; carbonization; mesophase; optical texture

PL

pak węglowy; zwęglanie; faza pośrednia; tekstura optyczna

• Wydawca: West Pomeranian University of Technology. Publishing House
• Czasopismo: Polish Journal of Chemical Technology
• Rocznik: 2001
• Tom: Vol. 3, nr 1
• Strony: 7--14
• Opis fizyczny: Bibliogr. 21 poz., tab., rys., wykr.

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 J.

• 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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