Structural Features of Activated Carbon Produced From Oil Sands Coke

The physical and structural properties of oil sands coke were investigated in an attempt to produce activated carbon from this material via steam activation. Although the activation process resulted in over 60 wt. % burnoff from the starting raw coke, the particle size distribution of the activated coke was similar or slightly larger than that of the raw coke. The changes in bulk density with activation showed a linear decrease with activation, thus indicating that the mass losses occurred mainly in the interior of the coke particles. Absolute density measurements showed an increasing trend with activation between a mass burnoff of 35 wt.% and 50 wt.%., which is consistent with a modification in the amorphous structure within the coke matrix. Scanning electron microscopic examination of the structural features of the activated coke revealed hollow spherical particles composed of concentric layers of carbonaceous matter with void volumes between the layers. The formation of the concentric layers promotes the activation process, thus enhancing internal surface area development.