Analysis of dynamic kinetic data from solid-state reactions

The kinetics of heterogeneous reactions, involving one reactant in the solid phase, usually follow the lawα=K _∞ exp(?E/kT)f(1?α), where α is the degree of conversion of the solid, andK _∞ andE are the kinetic constants. A critical examination is given of the various methods which are currently used to analyse dynamic experimental data. The limitations of these methods and their insensitivity to the form off(1-α) are pointed out. An alternative approach free from these limitations is suggested. In this,f(1?α) is determined from isothermal experiments, and then the dynamic data are accurately analyzed to obtain the values of the kinetic constants. A case study is given to elucidate the applicability of the approach.