| Abstract
| - This paper presents a detailed study of the air reactivity of petroleum cokes measured at temperatures between400 and 600 °C using a combination of characterization techniques and reactivity measurements. Themicrostructure of the coke was found to comprise an essentially inaccessible pore system at low temperaturesof 77−273 K used in characterization, and it is more accessible to oxygen at higher temperatures of about773 K used in oxidation. The correlation of reactivity data using the random pore model suggests that thetrue micropore area is significantly larger than that measured using physical gas adsorption methods. Thedifference in surface area can be attributed to the low kinetic energy of gas molecules at the lower temperaturesof characterization; as a result, they are unable to overcome the pore mouth energy barrier. By examining thevariation of coke structure with burnoff level, we find that most of the internal reaction occurs in pores in thenarrow pore width range 1−2 nm. For pores greater than 2 nm, however, the surface areas remains essentiallyconstant with burnoff level. The apparent activation energy of the coke-air reaction derived from the extractedrate constants falls in the range 145−160 kJ/mol.
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