Intrinsic reactivity of petroleum coke to oxygen

Abstract

The kinetics of the reaction of petroleum coke with oxygen 2 were investigated using a continuous flow reaction system incorporating facilities for reactant modulation. An apparent order in O 2 of 0.6 and activation energies in the range 151–167 kJ mol −1 were observed. Measurement of the surface areas of partially combusted coke samples enabled intrinsic reaction rates (ρ i) to be calculated. Regression analyses of all data after correction to a common O 2 pressure of 21.3 kPa gave the following relation for the intrinsic reactivity of petroleum coke in the region of 750 K: ρ = 133 × 10 6 exp exp(− 158.6/ RT) g m −2 min −1 where: R = the gas constant and T = the temperature. As combustion proceeded, pores in the radius range 0.5–5 μm were enlarged. Present kinetic results were compared with earlier data obtained at high temperatures (1200–2300 K) for a similar petroleum coke. After correction for mass transfer limitations, intrinsic rates derived from the high-temperature data correlated well with the present low-temperature results.