A quantitative study of solid surface heterogeneity based on the statistical rate theory for analyzing spectra of controlled-rate thermal analysis

Abstract

Controlled-rate thermal analysis (CRTA) spectra are obtained by adjusting the heating rate in such a way that the rate of desorption can be constant. A quantitative analysis of the obtained spectra is presented, based on more refined theoretical treatment that offers new possibilities of getting more information from the experimental CRTA thermodesorption spectra. The method we propose makes it possible to obtain a desorption energy distribution function without any additional experimental information. For the purpose of illustration, an analysis is made of water desorption from a synthetic apatite mineral under CRTA conditions. Also, numerical simulations of the CRTA spectra are presented showing some basic features of the equations used for the analysis of experimental data. All calculations are based on the statistical rate theory.