Biofuels, Bioproducts and Biorefining, 2025 (SCI-Expanded, Scopus)
This study investigates the co-pyrolytic behavior of waste tires (WT) and Platanus orientalis leaves (SL) as hybrid feedstocks for thermochemical valorization. Pyrolysis experiments were conducted under nitrogen atmosphere using thermogravimetric analysis across a temperature range of ambient to 745 °C, with heating rates of 5, 10, 15, 20, and 25 K min−1. Five blend ratios (100% WT, 75/25, 50/50, 25/75, 100% SL by mass) were assessed to evaluate thermal degradation profiles and kinetic characteristics. A Box–Behnken experimental design within the response surface methodology (RSM) framework was employed to optimize the effects of temperature, heating rate, and blend ratio on pyrolysis performance. The statistical model showed a high predictive capability with R2 >0.995. Kinetic parameters were calculated using Coats–Redfern, Flynn–Wall–Ozawa, and Kissinger methods, with activation energies for the major decomposition stage (Stage 3C) ranging from 114.3 to 125.2 kJ mol−1. A significant negative correlation was found between activation energy and SL content (r = −0.82), while WT content showed a positive correlation (r = 0.87), indicating that biomass reduces the energy barrier for thermal degradation. Fourier transform infrared analysis confirmed the breakdown of functional groups such as .OH, C.O, and aromatic C.C after pyrolysis, indicating extensive structural transformation. Scanning electron microscopy imaging revealed morphological changes from fibrous structures in SL to carbonized, fractured surfaces in the char. Energy-dispersive X-ray spectroscopy analysis indicated a high carbon content (91.2%), supporting the suitability of the product for energy applications. Overall, the study demonstrates the synergistic potential of WT and SL in co-pyrolysis, improving thermal behavior, reducing activation energy, and yielding carbon-rich products. These findings support the development of integrated waste-to-energy strategies aligned with circular economy principles.