Comparing the kinetic and thermodynamic behavior of mango kernel and its two main components through pyrolysis and combustion

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The agro-industrial and food industry generates tons of bio-waste such as mango waste ( Mangifera Indica ) that has a negative impact on the environment if not managed effectively. This study characterized the physicochemical properties and thermal behavior of mango kernel and its components (seed and pericarp) to propose a suitable thermochemical conversion route for its valorization. The study revealed that mango kernel (MK), seed (MS), and pericarp (MP) possess high volatile matter and fixed carbon contents, making them well-suited for pyrolysis to generate biofuel and biochar. MK and MS showed better combustion performance than MP due to higher lower heating values (LHV) and lower ash content. Moreover, MK and MS exhibited greater potential for gasification and potassium recovery due to favorable thermal, chemical, and mineral compositions. Thermogravimetric analysis (TGA) using iso -conversional methods demonstrated significant thermal stability and non-spontaneous reactions across all samples, while Gibbs free energy changes (ΔG) indicated considerable energy extraction potential. Catalytic indices derived from metal content further confirmed the suitability of mango waste for thermochemical valorization. Although the components showed compatibility without negative synergistic effects, separating the seed and pericarp from the kernel could improve energy efficiency, product quality, and process flexibility. Kinetic analyses revealed activation energies (E a ) during pyrolysis ranging from 149–310 kJ/mol for MK, 190–407 kJ/mol for MS, and 157–366 kJ/mol for MP, with ΔG up to 194 kJ/mol. Combustion required lower activation energies, 122 kJ/mol for MK and ∼133 kJ/mol for MS and MP, indicating easier ignition of MK. Reaction mechanism modeling confirmed complex kinetic transitions with the conversion. These findings offer a solid foundation for optimizing the thermochemical conversion of mango waste into energy products and enabling the synthesis of advanced materials.