@article{10272/28031, year = {2026}, url = {https://hdl.handle.net/10272/28031}, abstract = {The present study investigates the pyrolysis kinetics of raw (undigested) sewage sludge and evaluates the effect of three low-cost catalysts (CaO, MgO, and Al2O3). The activation energies (Ea) were determined by means of the Flynn–Wall–Ozawa method. The raw sludge displayed a three-phase Ea profile, which suggests sequential decomposition of heterogeneous biopolymers. Among the catalysts, CaO exhibited the most significant reduction in Ea within the medium conversion range (α ~ 0.4–0.7). The effect of MgO was found to be reaction stage-dependent, while Al2O3 was observed to increase Ea in the initial stages, thus potentially promoting condensation reactions. The findings provide a robust foundation for the direct pyrolysis of raw sludge with low-cost catalysts, a process that has been demonstrated to enhance energy recovery in a single step, thereby circumventing the losses that are typically associated with prior anaerobic digestion.}, organization = {Universidad de Huelva/CBUA}, publisher = {Springer Nature}, keywords = {Sewage sludge}, keywords = {Kinetic}, keywords = {Pyrolysis}, keywords = {Flynn–Wall–Ozawa method}, title = {Direct pyrolysis of catalysed raw sewage sludge unlocks superior energy recovery: a kinetic evidence}, doi = {10.1007/s11356-026-37547-9}, author = {Palma López, Alberto and Lozano Calvo, Susana and Ruiz Montoya, Mercedes and Díaz Blanco, Manuel Jesús}, }