Effect of coal rank on the properties of coal-based activated carbon honeycomb monoliths

Activated carbon honeycombs (ACHs) were prepared by extrusion of honeycombs from a mixture of coal, coal tar, bean oil, methylcellulose and water, followed by carbonization and steam activation. Three Chinese coals, Qujing, Shenfu and Datong, were used as carbon precursors. The ACH monoliths obtained were characterized by N-2 adsorption, thermo-gravimetry and compression tests. Results show that both coal rank and activation time have great a impact on the pore size distribution and mechanical strength. The ACHs from Datong obtained under optimum conditions have the highest BET surface area( 884 m(2)/g), the highest ignition temperature (535 degrees C) and the highest mechanical strength( > 13 MPa) among the three coals. The mechanical strength of the ACH monoliths decreases with increasing macro-pore volume. The ignition temperature is hardly affected by ash content but decreases with increasing volatile content.