Thermal studies of biomass obtained from the seeds of Syzygium cumini and Cassia fistula L. and peel of Cassia fistula L. fruit

Abstract

The potential of thermo-chemical performance of three biomass materials namely Syzygium cumini seeds (JP), Cassia fistula L. seed (AT), and Cassia fistula L. fruit peels (AP) has been investigated in detail in the present study. Thermo-gravimetric analysis (TGA) was conducted for pyrolysis kinetic parameters at various temperatures (heating rates). Five temperatures (10, 15, 20, 25, and 30 °C/min) and two model-free techniques (especially Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS)) were applied to evaluate the response. It was found that the respective average activation energies were 222.66, 200.82, and 224.57 kJ/mol for JP, AT, and AP, respectively, in the case of the FWO model, while the average activation energies 223.49, 201.19, and 227.43 kJ/mol were obtained by using the KAS model. The activation energy, enthalpy, and pre-exponential factor for the studied biomass materials are shown in the order of AP > JP > AT in both these models. Moreover, the highest values of pre-exponential factor were found for JP in FWO (1.27 × 1039) and KAS (1.81 × 1040) models. The active pyrolysis zone was also noticed in the temperature range of 175–600 °C, which represents the maximum weight loss range as well in the present study.