A method for the production of a carbon fiber precursor

US4756818A · kind A · utility

Assignee

• Rutgerswerke Aktiengesellschaft · DE

Inventors

• Siegfried Peter · Erlangen, DE
• Herbert Beneke · Castrop-Rauxel, DE
• Franz D. Oeste · Kirchhain, DE
• Wolfgang Fexer · Erlangen, DE
• Wolfgang Jaumann · Nuremberg, DE
• Manfred Meinbreckse · Friedrichsdorf, DE
• Joachim Kempfert · Kronberg, DE

Key dates

• Filing date: Feb 24, 1987
• Grant date: Jul 12, 1988
• Expiry date: Feb 24, 2007

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D01F9/15
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A method for the production of a carbon fiber precursor from coal tar pitch comprising extracting coal tar pitch at elevated temperatures and pressures with a mixture of a supercritical gas and an entraining agent to obtain a solution free of quinoline-insoluble components, recovering from the solution by lowering the pressure and/or raising the temperature to obtain at least one fraction selected from the group consisting of quinoline-soluble fraction and toluene-soluble fraction, treating the said fraction(s) at 380.degree. to 450.degree. C. under a non-oxidizing atmosphere at atmosphere pressure until 40 to 65% by volume of the product is converted into pitch containing mesophase, extracting the latter pitch with a mixture of supercritical gas and an entraining agent to remove isotropic pitch and recovering isotropic pitch with a mesophase content of at least 75% by volume, a pyridine-insoluble matter content of 20 to 50% by weight, a mean molecular weight of 900 to 1200 and a melting point of 330.degree. to 360.degree. C. and the isotropic pitch product produced therefrom and carbon fibers made from the isotropic pitch.