Aquilanti–Mundim deformed Arrhenius model in solid-state reactions: Theoretical evaluation using DSC experimental data

• Published in: Journal of thermal analysis and calorimetry 2016-12, Vol.126 (3), p.1175-1184
• Main Author: Luiggi Agreda, Ney J.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Measurement Science and Instrumentation; Physical Chemistry; Polymer Sciences
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-016-5566-8

Although the theoretical framework supporting the use of non-extensive statistical theory for the study of chemical reaction kinetics and solid-state diffusive reactions is well established, direct evaluation of the parameters involved—such as the case of pair ( d , ε ) appearing in the d -Arrhenius model—in the pertinent experimental data has yet to be generalized. This study proposes the use of “ d -Arrhenius log–log plots” instead of Arrhenius semilog plots as a tool to determine the kinetic parameters of a reaction and their application to two different solid-state reactions obtained by DSC measurements in an Al–Fe–Si alloy. The paper goes on to show that the data obtained by DSC using the Arrhenius law generate a single k ( T ), whereas resorting to the Aquilanti–Mundim deformed Arrhenius model generates a set of ( d , ε ) parameter pairs capable of reproducing the experimental data. Different ( d , ε ) pairs generate different k ( T ) ( d  = 0, ε  =  Q ) corresponding to the Arrhenius pair. The effect of the different ( d , ε ) pairs on the different functions related to the kinetics of the reaction is examined. Graphical Abstract AMDA graph showing linearity for different ( d , ε ) pairs obtained from the precipitation reaction Guinier–Preston zones measured by DSC in an AA8011 commercial alloy (Superior) and Q activation energy for different pairs (bottom). The pair of Arrhenius (0, Q ) in both graphs is represented by perpendicular and horizontal lines, respectively.