Thermal Degradation Properties and Thermodynamics of Cellulosic Biomasses

In this article, a compilation of articles examining the thermal and thermodynamic degradation of cellulose cores that occur naturally in nature and are produced as waste from foods consumed as food in daily life is presented. Thermal degradation behavior and thermodynamic properties of cellulosic biomasses are investigated using thermogravimetric analysis (TGA) using different atmospheres. The aim of the studies was to understand the degradation properties and evaluate the energy parameters that are critical for bioenergy applications. Many different methods are used to evaluate the kinetic parameters without assuming a specific reaction mechanism. These methods are divided into two groups: model-fitting and model-free. Degradation of cellulosic substances can be single- or multi-step according to their content. A thermodynamic triplet can be calculated from these calculations. Activation energy values were determined as a function of the degree of conversion by revealing the different stages in the degradation process corresponding to the decomposition of hemicellulose, cellulose, and lignin. Thermodynamic parameters such as enthalpy (ΔH), Gibbs free energy (ΔG), and entropy (ΔS) were also calculated to evaluate the energetic feasibility and spontaneity of thermal reactions. The results show that cellulosic biomass exhibits a multistep degradation process with a significant change in activation energy across the conversion range. These findings provide valuable insights for the optimization of thermal conversion technologies such as pyrolysis and gasification and provide a basis for designing efficient biomass-to-energy systems.