Pyrolytic kinetics and thermodynamic analyses of date seeds at different heating rates using the Coats–Redfern method

Abstract

Pyrolytic kinetic and thermodynamic analyses of date seeds were performed using thermogravimetric analysis (TGA) at different heating rates (10, 20, 30, and 40 °C/min) ranging from 20 °C to 900 °C. The curves of TGA and differential thermogravimetric analysis (DTG) showed that pyrolysis of date seeds consists of three areas of mass loss: dehydration, devolatilistion and char formation. The temperature range of each of these regions varies with heating rate. The Coats-Redfern method was used to perform the kinetic and thermodynamic evaluations for the devolatilisation region at different heating rates. The Zhuravlev diffusion equation proved to be the best–fit model with the highest regression coefficient values in the devolatilistion region. The average activation energy value for the devolatilistion region was estimated to be 186 kJ/mol. The kinetic data were used to determine the thermodynamic parameters (ΔH, ΔG, and ΔS). The data presented here are useful for describing date seeds as a significant raw material for pyrolysis, designing pyrolysis reactors, and understanding the mechanism of date seed pyrolysis in detail.