A weighted mean activation energy method was applied to describe the reactivity and combustibility of crude oils via simultaneous TG/DTG. Thermal experiments were conducted with a non-isothermal method at a heating rate of 10‡C min−1 with excess air. Reaction rates increased progressively with increasing temperature. The rate data were fitted to an Arrhenius equation; the plots showed three distinct reaction regions. Weighted mean activation energies (Ewm), of the crude oils were calculated and a correlation was established betweenEwm, API gravity and peak temperatures during high-temperature oxidation.
Thermal analysis increasingly being used to obtain kinetic data relating to sample decomposition. This work involves a comparative study of several methods used to analyse DSC and TG/DTG data obtained on the oxidation of Beypazari lignite. A general computer program was developed and the methods are compared with regard to their accuracy and the ease of interpretation of the kinetics of thermal decomposition. For this study, the ratio method was regarded as the preferred method, because it permits the estimation of reaction order, activation energy and Arrhenius constant simultaneously from a single experiment.