Kinetic and thermodynamic study of maize stalk biomass using thermogravimetric analysis

Abstract Investigating thermodynamic and kinetic aspects is crucial for assessing efficiency of converting biomass into energy. This study presents kinetic and thermodynamic characteristics of maize stalk using thermogravimetric analysis. The novelty of this research stems from the combination of kinetic and thermodynamic analysis, the application of multiple kinetic models and understanding of pyrolysis-based bioenergy production process from maize stalk. Analysis was performed using a temperature range of 25–650 °C employing 5, 10, 15 and 20 °C/min heating rate. The temperature range of 250–650 °C was selected to analyze the complete decomposition of the three main components of maize stalk i.e. hemicellulose, cellulose and lignin and to prevent the decomposition of inorganic substances such as CaCO 3 which decompose at high temperature. The apparent activation energy values were evaluated using Kissinger-Akahira-Sunose (KAS), Friedman and Ozawa-Flynn-Wall (OFW) models. The resulting mean apparent E a values calculated for KAS, Friedman and OFW were 167.86, 177.34 and 162.96 kJ/mol, accordingly. Additionally, Gibbs free energy (ΔG) values were 164.17 kJ/mol, enthalpy (ΔH) −178.31 J/molK and entropy (ΔS) 285.59 kJ/mol, respectively. These findings suggest that maize stalk holds promise as a potential bioenergy source, aligning with sustainable goals and waste-to-energy strategies.