The effect of graphitisation by the variation of annealing time and temperature on the pore structure and apparent gasification rate at 1200 and 1500°C was investigated. The graphitisation degree of three kinds of coke used in this study was increased with annealing time and temperature. The increase in porosity of annealed coke sample is ascribed to the formation of silicon carbide. Annealing at 1200°C had less significant effect on the change of porosity in comparison with annealing at 1500°C. The mean area of pores was decreased, and pore density was increased with increasing annealing time while annealing had marginal influence on the pore shape. The apparent gasification rates of Coke 1 and Coke 2 with H2O were decreased by annealing, but 3 h of annealing increased the apparent gasification rate of Coke 3. The correlation between apparent gasification rate with H2O and macroporosity or graphitisation degree was investigated.
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