Effects of FeCl3 (intercalated or not in graphite) on the pyrolysis of coal or coal tar pitch

Addition of iron chloride to coal tar pitch or coal before carbonization speeds up mesophase growth and increases the yield of an iron loaded microporous char. After steam activation a mesoporous activated carbon with specific adsorbents properties can be obtained. Iron oxide (magnetite) at the internal surface of the carbon plays the role of a basic centre for the catalytic oxidation of polluting gas. The present work deals with the effect on the pyrolysis and activation processes of the mode of introduction of FeCl3-either free or intercalated in graphite (GIC)-in coal tar pitch (CTP), in coking coal itself, or in a mixture of coal and CTP. Lewis acid effects on oil, methane, dihydrogen and carbon monoxide evolution could be correlated with those on mesophase growth, on char yield and on the properties of the steam activated chars. The study shows that free FeCl3 loading can be advantageously used to prepare cheap adsorbents. (C) 1998 Elsevier Science Ltd. All rights reserved.