| 摘要 |
<p>PURPOSE:To obtain economically carbon black exhibiting low pH and having excellent suitability such as dispersibility as a colorant for inks, by a method wherein green coke obtd. from thermal cracking of heavy oil is calcined in an oxidizing atmosphere and then pulverized. CONSTITUTION:Heavy oil such as straight-run residual oil, asphalt or thermal cracking tar is thermally cracked in a delayed cooker apparatus to obtain green coke which is then calcined in an oxidizing atmosphere by using a calcination furnace such as a rotary kiln. Then the resulting calcined coke is pulverized by means of a jet mill employing compressed air or steam to obtain the oxidized carbon balck fine powder having a particle diameter of 1mu or smaller. The resulting carbon black has a pH of 4 or below and excellent optical suitability and dispersibility, and is suitable as a colorant for inks, paints and lacquers.</p> |
