Vol 63 No 1 (2018): Journal of the Chilean Chemical Society
Original Research Papers


Naushad Ahmad
Department of Chemistry, College of Science, Riyadh-11451, King Saud University
Manawwer Alam
Research Centre, College of Science, Riyadh-11451, King Saud University
Mu. Naushad
Department of Chemistry, College of Science, Riyadh-11451, King Saud University
Anees A. Ansari
King Abdullah Institute for Nanotechnology, Riyadh-11451, King Saud University
Basel F. Alrayes
Central Laboratory, College of Science, Riyadh-11451, King Saud University
Mshari A. Alotaibe
Department of Chemistry, College of Science, Prince Sattam bin Abdulaziz, University
Published April 25, 2018
  • Tannic acid,
  • Thermal decomposition,
  • kinetics,
  • Isoconversional methods
How to Cite
Ahmad, N., Alam, M., Naushad, M., Ansari, A. A., Alrayes, B. F., & Alotaibe, M. A. (2018). THERMAL DECOMPOSITION AND KINETIC STUDIES OF TANNIC ACID USING MODEL FREE-METHODS. Journal of the Chilean Chemical Society, 63(1). Retrieved from


In this manuscript, thermal and kinetic features of a tannic acid was studied by simultaneous TG-DTA techniques in the nitrogen atmosphere at four heating rate. It was observed that thermal decomposition of its constituents occurred in two steps. Model free isoconversional methods namely modified Coast-Redfern (CR), Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO) and Freidman (FR) were used for revelation of decomposition kinetics (Ea and lnA) on the whole range of temperature. Mechanisms of decomposition process have been found to follow first order of decomposition rate. Reaction order does not have a substantial effect on the process because of the high value of pre-exponential factor. It was observed that, at the last stage of decomposition process, value of activation energy and pre-exponential factor increased. Decomposition of tannic acid was confirmed by IR spectroscopy.


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