A Simple Method for Estimating <i>f</i><i>(E)</i> and <i>k</i>₀(<i>E</i>) in the Distributed Activation Energy Model

Abstract

A new method that is simpler and more accurate than the author's previous method is presented for estimating f(E) and k0(E) in the distributed activation energy model. It utilizes at least three sets of experimental data obtained at different heating rates, a. The Arrhenius plot of ln(a/T2) vs 1/T (T: temperature) at the same conversion level allows determination of both E and k0 at that level by introducing an approximation. f(E) and k0(E), unique to the reaction system of concern, can then be obtained by changing the conversion level. The validity and accuracy of this new method are shown through model calculations. The method does not require a priori assumptions for f(E) and k0(E). The f(E) curves and the k0 vs E relationships for the pyrolysis reactions of Argonne premium coals estimated by this method were successfully used to predict the weight loss curves at markedly different heating conditions.