Thermal Decomposition Kinetics of <i>Dracaena Draco</i> Agro Waste: An Investigation Employing Multicomponent Models and Gaussian Deconvolution

This study examines the pyrolysis behavior, kinetic parameters, and thermodynamic features of Dracaena draco fibers (DdFs), an underutilized subtropical agro-waste from areas such as Algeria and the Canary Islands. With a low ash content (2.10%, reducing slagging issues compared to rice husk’s ~ 15%), high volatile matter (77.29%, favoring bio-oil yields > 50%), and elevated lignin (26.78%, enhancing energy density with HHV 19.95 MJ/kg), DdFs offer unique advantages over other biomasses that have been extensively studied, like rice husk or sugarcane bagasse. Using thermogravimetric analysis, samples werea pyrolyzed in a nitrogen environment at heating rates ranging from ambient to 800°C at rates of 5–30 °C/min. By better resolving early-stage drying effects, a novel four-parallel Gaussian kinetic model that incorporates pseudo-drying (PO-D) along with pseudo-hemicellulose (PO-H), pseudo-cellulose (PO-C), and pseudo-lignin (PO-L) accurately describes decomposition with R2 > 0.99, RMSE < 0.05, and χ2 < 0.01. This model outperforms conventional three-component models. The mean apparent activation energies of 146.93 kJ/mol (PO-H), 127.76 kJ/mol (PO-C), and 173.94 kJ/mol (PO-L) obtained using model-free isoconversional methods (Starink, Kissinger-Akahira-Sunose, and Ozawa-Flynn-Wall) show better thermal stability for lignin charring than agave (PO-L ~ 106 kJ/mol).