Thermogravimetric analysis and the fitting model kinetic evaluation of corn silk thermal decomposition under an inert atmosphere

Abstract

The thermal behavior of corn silk pyrolysis under nitrogen atmosphere has been studied through the thermogravimetric analyzer. The drying process of the original sample was performed by means of an oven at 100°C for 90 minutes. The dry sample subsequently ground and sieved for a mesh size of 60. Approximately 11 mg of the sample was weighed into the crucible. The constant heating program of 10°C/min was imposed on the sample start from room temperature till to 900°C. The 50 ml/min of nitrogen was continuously flowed into the inner of the chamber to ensure the inert conditions. The differential fitting model of Arrhenius was occupied to evaluate the kinetic parameters. The result shows that corn silk was decomposed into the three stages during the pyrolysis process. These three stages initiated by the dehydration process from room environment till to 154°C and then followed by the most massive degradation of an organic component in the main devolatilization zone at the temperature range of 154-514°C and finally rest of material was undergoing slow decomposition till to 900°C. The respective activation energy (E), logarithmic of the pre-exponential factor (log A) and reaction order (n) of the corn silk pyrolysis were 207.37 kJ/mol, 19.15/min and 5.2.