Experimental study on thermal decomposition kinetics of talc under the condition of air atmosphere

doi:10.7523/j.issn.2095-6134.2015.01.012

Abstract

Abstract:

Study on thermal decomposition kinetics of hydrous minerals is important to the exploration of the formation mechanisms of intermediate-deep earthquakes occurred in subduction zone. In the present work thermal decomposition of talc was studied by using thermogravimetric (TG) techniques under the condition of dynamical air atmosphere. The model-free methods including Friedman and FWO were employed to determine the activation energy (E_{a) and the pre-exponential factor (A). Based on the initial values derived from Friedman method, the most probable kinetic model of the dehydration reaction was obtained by using the multivariate non-linear regression approach. The results showed that talc decomposed in the temperature range of 830~1 050℃ and the most probable kinetic model could be expressed as f(α)=(1-α)ⁿ and G(α)=(1-(1-α)^(1-n))/(1-n), with the derived values of 1.7,344.2 kJ/mol, and 4.9E12 s^-1 for n, E_{a, and A, respectively.}}

Key words: talc, dehydration kinetics, thermogravimetric

CLC Number:

O657.99

WANG Yan, WANG Duojun, YI Li. Experimental study on thermal decomposition kinetics of talc under the condition of air atmosphere[J]. , 2015, 32(1): 70-73.

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