Carbonization of coal-tar pitch under controlled atmosphere—Part II: Effect of temperature and pressure on the electrical property evolution of the formed green coke

Abstract

The carbonization of an industrial coal-tar pitch was studied by using a tube bomb, as a function of carbonization temperature (550 °C–580 °C) and inert gas pressure (1–20 bar), and resultant green cokes were evaluated according to electrical resistivity determined using the Van der Pauw method. At 550 °C, the carbonization pressure increase leads to an uniaxial arrangement of the produced green coke sample and to a progressive increase of the resistivity component perpendicular to the tube bomb axis. At 580 °C, these changes appear only above 15 bar. These results are in good agreement with those obtained in the first part of this work, confirming the intimate correlation between carbonization temperature and pressure and the necessity of a compromise between them, to produce green cokes with oriented uniaxial texture.