Carbonization of coal pitch with graphite additives

The influence of added pyrolytic graphite and graphite foam on the crystalline structure of the product formed in the carbonization of moderate-temperature coal pitch at 900°C is investigated by X-ray diffraction analysis. All the additives catalyze the formation of graphite structures in pitch carbonization. However, no direct dependence of the catalytic efficiency on the structure of the carbon additive or its specific surface is observed. In the presence of graphite additives with a specific surface of 4–12 m2/g, more than 20% of a crystalline fraction is formed in the carbonization of pitch. This fraction is highly ordered, with large crystallites. On adding graphite foam, with a high specific surface (110 m2/g) and low packing density (4 g/L), the formation of graphite structures on pitch carbonization is less effective.