A generalized solid state kinetic expression for reaction interface-controlled reactivity

The ICTAC-recommended approach was used to characterize the gasification of high-purity, highly crystalline, large natural graphite flakes in oxygen. The average activation energy was found to be 157.7 ± 4.2 kJ mol−1. The graphite properties and the simple gasification reaction taking place make this an ideal material for the study of reaction interface-controlled reactivity. Based on simple structural and geometrical observations, it was expected that the conversion function would be that of a shrinking disc. However, the experimental conversion function exhibited a behaviour which could not be linked to any of the commonly established reaction models.