Integral, differential and advanced isoconversional methods: Complex mechanisms and isothermal predicted conversion–time curves

Differences in the activation energy values determined from differential and integral isoconversional methods have been already reported. For a long time it was believed that these differences could be due to the approximations used for the temperature integral used in integral methods. In fact, this study clearly shows that the assumption of a constant activation energy is a key parameter that must be considered in the case of a complex reaction mechanism leading to a great variation of the effective activation energy on conversion. The study also shows that the advanced integral method of Vyazovkin gives more accurate results. For short time predictions, all the methods tested gave satisfactory results but for long time simulations the conventional integral methods may lead to inaccurate outcomes.