A simple and precise incremental isoconversional integral method based on Li-Tang (LT) method is proposed for kinetic analysis of solid thermal decomposition, in order to evaluate the activation energy as a function of conversion degree. The new method overcomes the limitation of LT method in which the calculated activation energy is influenced by the lower limit of integration. By applying the new method to kinetic analysis of both the simulated nonisothermal case and experimental case of strontium carbonate thermal decomposition, it is shown that the dependence of activation energy on conversion degree evaluated by the new method is consistent with those obtained by Friedman (FR) method and the modified Vyazovkin method. As the new method is free from approximating the temperature integral and not sensitive to the noise of the kinetic data, it is believed to be more convenient in nonisothermal kinetic analysis of solid decompositions.
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