Determination and comparison of combustion kinetics parameters of peanut shells, cashew nut shells, palm nut shells, and millet stem

The energetic valorization of agricultural or forest residues, allows us to preserve, our ecosystem under the threat of the disappearance of certain vegetable species, to the abusive cutting of wood. The study carried out on this paper consists in making a kinetic of thermal decomposition of the coproducts: peanut shells (PNS), cashew nut shells (CNS), palm nut shells (PLS), and millet stems (MS) coming from the natural region of Casamance. Thermogravimetric analysis at three heating rates of 5°C.min-1, 10°C.min-1 and 20°C.min-1 under pure air up to $800^{\circ}\mathrm{C}$ was necessary to conduct our kinetic study. This thermal degradation of our samples allowed deconvolution by the Fraser-Suzuki method, which assumes that decomposition occurs independently for each pseudo-component (hemicelluloses, cellulose, and lignin). Friedmann (Fri), Kissinger-Akahira-Sunose (KAS), and Flynn-Wall-Ozawa (FWO) methods were to determine the activation energy of the three pseudo-components of our studied coproducts. The average activation energy being the energy required to decompose a material, was higher than for cellulose for all four coproducts. The latter varies from 116,30 MJ.mol-1, 87,84116,30 $\mathrm{M}\mathrm{J}.\mathrm{m}\mathrm{ol}^{-1}$; 209,55 MJ.mol-1 and 339,64 MJ.mol-1 for PNS, CNS, PLS and MS respectively.