Investigation on kinetic and thermodynamic parameters of Cerbera manghas de-oiled seed as renewable energy during the pyrolysis process

Abstract

The investigation of renewable energy sources is critical regarding the availability of energy in the future. This study was aimed to understand the potential of Cerbera manghas de-oiled seed by investigating the kinetic and thermodynamic parameters during the pyrolysis process. The de-oiled seed was obtained by the pressing of the seed at 33.81 N/m2 to release its oil content. The de-oiled seed sample was subjected to the thermogravimetric analyzer (Mettler Toledo TGA-DSC1) to knowing the characteristics of the sample during the time of thermal decomposition. The kinetic parameters were studied using the Coats-Redfern method. The results showed that the de-oiled seed decomposed into three stages; the first stage occurs at temperatures of 25-178 °C, the second stage occurs at temperatures of 189-488 °C, and the third stage at temperatures of 500-900 °C, with the very low residue of 15.4 % was leftover at the final thermal processes. The kinetics analysis resulted in the activation energy, reaction order, and pre-exponential factor of 27.42 kJ/mol, 0.94, and 68,64 min−1, respectively. Following the kinetic results, then the thermodynamic parameters were analyzed and resulted in the values of ΔH (enthalpy), ΔG (Gibbs free energy), and ΔS (entropy) that were 22.40 kJ/mol, 171.86 kJ/mol, and -0.2230 kJ/mol, respectively. From the results of this study, it could conclude that the de-oiled seed of Cerbera manghas has potential as a renewable energy source.