| 摘要 |
PURPOSE:To obtain high-quality soft pitch of a small amount of low-boiling point fraction, with little variation in the softening point, useful for carbon electrodes, etc., by incorporating high-boiling point tar-based heavy oil in raw coal tar followed by distillation treatment. CONSTITUTION:Raw coal tar is incorporated with e.g. 15wt% of tar-based heavy oil having an average boiling point higher than the softening point (determined by ring and ball method) of the objective soft pitch by >=200 deg.C (e.g. anthracene oil with an average boiling point 340 deg.C) followed by conventional distillation treatment of the resulting blend oil to obtain the objective soft pitch.
|
