Authors: J Farjas P Roura
Publish Date: 2011/03/30
Volume: 105, Issue: 3, Pages: 757-766
Abstract
There are many mathematical methods to determine the activation energy from nonisothermal experiments However controversies arise over the different values obtained by these methods We will show that the origin of these discrepancies is either inaccurate approximations of the socalled temperature integral or the occurrence of complex transformations We will review and compare the most commonly used methods For those methods that lack accuracy we will introduce simple numerical modifications to make them exact In addition we will introduce a new method that allows easy and accurate determination of the activation energyFrom Eqs 34 and 35 one can state that the accuracy of FWO and KAS methods depends exclusively on the reduced activation energy at a given temperature x while for Ortega’s method Eq 36 the accuracy also depends on the reaction model and the finite differences Δα Indeed the smaller Δα the smaller the relative error This leads to a significantly better accuracy for Ortega’s method when compared to FWO and KAS
Keywords: