Kinetic and thermodynamic analyses of date palm surface fibers pyrolysis using Coats-Redfern method.

This study presents the thermo-kinetics and thermodynamic analyses of date palm surface fibers (DPSFs) using thermogravimetric analysis. DPSFs were heated non-isothermally from 20 to 800 OC at a ramp rate of 10 OC/min in nitrogen atmosphere. Thermogravimetric analysis indicated that there have been two stages for pyrolysis of DPSFs. Kinetic and thermodynamic parameters have been calculated for the second stage which is further subdivided into two mass-loss regions. The low-temperature stable components were decomposed in a temperature range of 270–390 OC and high-temperature stable components were degraded in a temperature range of 390–600 OC. The Coats–Redfern integral method was employed with 21 different kinetic models from four major solid-state reaction mechanisms. Among all models, the two diffusion models: Ginstling–Brounshtein and Ginstling diffusion were the best fitted models with highest regression coefficient values (R2 > 0.99) in both mass-loss regions. For mass-loss regions: I (270–390 OC) and II (390–600 OC), the activation energy values were found to be 96–98 and 113–114 kJ/mol, respectively. Thermodynamic parameters (ΔH, ΔG, ΔS) were calculated using kinetic data. The findings reported herein are helpful in characterizing date palm fibers as a source of energy, designing reactors, producing chemicals, and understanding the properties of surface fibers for making composites. [Display omitted] • Kinetic and thermodynamic analysis of date palm surface fibers using Coats Redfern method. • Kinetic mechanisms from chemical reactions and diffusion, geometric, and nucleation models. • Two-stage mechanism has been observed in pyrolysis of date palm surface fibers. • Coats-Redfern method showed that palm fibers pyrolysis follows diffusion mechanism. • Ginstling–Brounshtein equation and Ginstling equation (4-D diffusion) are best fitted models. [ABSTRACT FROM AUTHOR]