Non–isothermal kinetics of degradation of chitin and chitosan

نویسندگان

  • Dilyana Zvezdova
  • Velyana Georgieva
  • Lyubomir Vlaev
چکیده

Thermogravimetric studies of chitin and chitosan in air atmosphere were carried out at six rates of linear increase of the temperature. The kinetics and mechanism of the thermal decomposition reaction were evaluated from the TG data using recommended from ICTAC kinetics committee isoconversional calculation procedure of Kissinger-Akahira-Sunose, as well as 27 mechanism functions. The values of the apparent activation energy E, pre-exponential factor A in Arrhenius equation, as well as the changes of entropy ∆S ≠ , enthalpy ∆H ≠ and Gibbs free energy ∆G ≠ for the formation of the activated complex from the reagent are calculated.

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تاریخ انتشار 2012