Assessment of the thermal degradation kinetics of fresh green coconut husk (Cocos nucifera L.) powder and after methyl levulinate production

Abstract

This study describes the recycling of green coconut husk powder (CHP) aimed at the sustainable production of methyl levulinate. The preliminary step involved thermogravimetric analysis of green (CHP) and residues after synthesis of methyl levulinate with the catalyst’s aluminum sulfate (CHP-AS) and titanium dioxide (CHP-TD), based on a degradation and determination of activation energy using the Ozawa-Flynn-Wall (OWF) method. Thermogravimetric analyses showed significant differences between the main constituents of CHP, CHP-AS and CHP-TD residues: hemicellulose (18.18, 9.78 and 12.17%), cellulose (44.65, 26.18 and 44.23%) and lignin (20.09, 19.89 and 19.58%), respectively. The methyl levulinate concentration obtained by the reaction between CHP and aluminum sulfate was 16.53 g.L-1, due to the participation of hemicellulose and cellulose. The results showed that the activation energies calculated using the OFW method were 142 kJ.mol-1 (CHP), 125 kJ.mol-1 (CHP-AS) and 180 kJ.mol-1 (CHP-TD).