MANUFACTURE OF NEEDLEELIKE COKE

摘要

Coal tar pitch is liquified at temperature of from about 135 DEG C. to 280 DEG C. The liquid coal tar pitch is filtered through a sieve with apertures from about 100 to 220 mu m and with a closed surface area of at least 75 percent of the total sieve surface under pressures of from about 2 to 10 bar until a filter cake of a height of from about 40 to 80 mm forms above the sieve for separating ash, soot and quinoline insoluble particles from the liquid. Then the filtrate obtained is subjected to a coking process. The needle cokes resulting in accordance with the invention provide excellent materials for the production of graphite electrodes.