PURPOSE: The titled raw pitch of low solftening temp. capable of easily forming mesophase in the preparation of precursor pitch, which is prepd. by thermally treating a heavy oil produced as a byproduct in the fluid catalytic cracking of a petroleum under hydrogen pressure and specified conditions.
CONSTITUTION: A heavy oil of b.p. ≥200°C produced as a byproduct in the preparation of light oil such as gasoline by fluid catalytic cracking of petroleum such as kerosene at about 450W550°C is thermally treated at 400W500°C under hydrogen pressure ≥20kg/cm2 in the absence of hydrogenation catalysts, to obtain raw pitch for carbon fiber.