A Comparison of Different Methods for the Estimation of Kinetic Data

Abstract

As could be shown in previous publications, the course of less complicated heterogeneous solid reactions can be described by the classical Arrhenius equation, modified for Thermal Analysis by introducing the linearly increasing temperature.

If n = 1, the interesting kinetic data, preexponential factor A and energy of activation E, can be found very easily from the position of the rate maximum.

Also if n ≠ 1, there is an easily practicable approximation method with the help of a plotter.

Looking for other easier procedures we tested the possibility to estimate E from the ratio of the rates v₁ and v₂ at the temperatures T₁ and T₂, respectively. This method is limited by the inaccuracy in evaluating the mentioned data. As the accuracy increased in the meantime /4/, this method also produces very satisfactory results. The very less expenditure is to be emphasized.

The different, purposeful simple, methods are proved by practical measurements.

The evident discrepancy of the results of one of these methods indicates the existence of various mechanisms in the different sections of the course of reaction.