Identification of the effective distribution function for determination of the distributed activation energy models using the maximum likelihood method: Isothermal thermogravimetric data

Abstract

The new procedure for identification of the effective distribution function for determination of the distributed activation energy models, which is based on use the maximum likelihood method (MLM), was established. The five different continuous probability functions (exponential, logistic, normal, gamma, and Weibull probability functions (the extended set of distributions)) were used for searching the best reactivity model for two heterogeneous processes: (a) the isothermal reduction process of nickel oxide under hydrogen atmosphere and (b) the isothermal degradation process of bisphenol-A polycarbonate (Lexan) under nitrogen atmosphere. The MLM showed that for both processes, the most suitable reactivity model

ICTAC Kinetics Committee recommendations for analysis of multi-step kinetics

“…A variety of analytical distributions have been used, most often a Gaussian distribution [30] but also Weibull [53,54,55], gamma [33,56,57], logistic [58,59], and pseudo-nth-order distributions [39]. It might be surprising to call the latter a distributed reactivity model, but it is mathematically similar to one limit of the gamma distribution and power-law temporal models, which are similar to a distribution of preexponential factors [33,39].…”