Advantages of Combined Kinetic Analysis of Experimental Data Obtained under Any Heating Profile

TLDR

Solid‑state reaction kinetics can be analyzed by combining data from experiments performed under various heating conditions. The method derives a logarithmic form of the general differential equation that applies to any heating profile, enabling analysis of multiple experiments—tested on simulated data and on crystallization of Ge₀.₃Sb₁.₄S₂.₇ glass and decomposition of siderite. The combined analysis using this logarithmic differential equation accurately determines kinetic parameters.

Abstract

The combined kinetic analysis of experimental data for solid-state reactions obtained under different experimental conditions is discussed. It is shown that the combined analysis of experimental data by means of the logarithmic expression of the general differential equation is a suitable method for the determination of the kinetic parameters. In the derivation of this equation, no assumptions are made of the way samples are heated. Therefore, any set of T − α − dα/dt data should fit the equation regardless of the experimental procedure, i.e., isothermal, linear heating rate, modulated temperature, sample controlled, etc, used for their calculation. Thus, it can be used for the analysis of series of experiments performed under the same or different conditions. The method is tested with simulated and experimental curves obtained under different conditions. The kinetics of crystallization of Ge0.3Sb1.4S2.7 glass is studied from a series of curves obtained under linear heating rate conditions. Additionally, the kinetics of decomposition of a siderite sample is also studied from a set of two curves obtained under linear heating and constant rate conditions.