Kinetic Analysis of CO_2 Gasification of Petroleum Coke at High Pressures

摘要

Determining the intrinsic gasification rates at high pressures is essential for designing and modeling high-pressure technologies. In this study, the intrinsic kinetics of CO_2 gasification of petroleum coke was investigated. The kinetic experiments were performed in a high-pressure thermogravimetric analysis unit at different temperatures (1173-1248 K) and pressures (0.1-2.4 MPa). Grain, volume, and random-pore models were applied to the experimental results to determine the kinetic parameters. The random-pore model provided the best fit to the data and was used to determine the kinetic parameters such that the activation energies and reaction orders could be determined. The reaction rates were described by a power law model that was half-order (0.49 ± 0.02) in CO_2 pressure. Similar activation energies, 260 ± 24 and 254 ± 12 kj/mol, were determined for pressures of 0.1 and 1.4 MPa, respectively, indicating similar reaction mechanisms for these pressures.