Kinetic Parameter Estimation of Lignite by Thermo-gravimetric Analysis

Abstract

AbstractTGA studies of lignite have been carried out. Lignite sample from Gujarat, India have been non-isothermally pyrolyzed using thermogravimetric analyzer and kinetics of decomposition of lignite was studied by non-isothermal method. The sample was heated over a range of temperature from room temperature to 1000°C with seven different heating rates of 5, 7, 10, 15, 20, 30, 50°C min-1 and non- isothermal weight loss was recorded for all heating rates. The weight loss curve showed that pyrolysis of lignite took place mainly in the range of 200-500°C. Two non-isothermal methods, namely the direct Arrhenius plot method and the integral method were applied for determination of kinetic parameters-activation energy (Ea) and frequency factor (A). The activation energy obtained by the direct Arrhenius plot method ranged between 60kJ/mol to 92kJ/mol. While the result obtained by integral method shows lesser value of activation energy (28kJ/mol to 50kJ/mol)