PRODUCTION OF PITCH FOR CARBONACEOUS MATERIAL

摘要

PURPOSE:To obtain a pitch for carbonaceous materials having a high carbon yield without increasing the softening point by removing a component soluble in an aqueous solution of an alkali from a mixture containing one or more of coal tar pitch, coal tar or petroleum-based thermally cracked heavy oil and then heat-treating the resultant mixture at a prescribed temperature. CONSTITUTION:An aqueous solution of an alkali at >=0.01 N concentration (e.g. NaOH) in an amount of 2-20 pts.wt. is added to 1 pt. wt. mixture containing one or more of coal tar pitch, coal tar or petroleum-based thermally cracked heavy oil to carry out treatment at a temperature within the range of ordinary temperature to the boiling point of the aqueous solution of the alkali for 10min to 10hr. A component soluble in the aqueous solution of the alkali (e.g. a compound containing oxygen atom) is then separated and removed from the obtained mixture. The resultant tar and pitch components are distilled or thermally reformed at a temperature within the range of 300-450 deg.C according to a conventional method to industrially and readily afford a pitch for carbonaceous materials having a high carbon yield without remarkably increasing the softening point.