Model-free and model-based kinetic analysis of Poplar fluff (Populus alba) pyrolysis process under dynamic conditions

Abstract

As representative among biomass feedstocks, Poplar fluff was chosen to analyze the pyrolysis properties of this new biofuel. Thermogravimetry under inert (argon) atmosphere at the heating rates of 5, 10, 15, and 20 °C min−1 was employed in the investigation of thermal processing of studied biomass. The determination of kinetic parameters and estimation of reaction mechanism function were done through application of the state-of-the-art NETZSCH Kinetics NEO software. With this aim, the various model-free models and model-based calculations were implemented. The obtained results showed that the most appropriate kinetic model to describe the thermal decomposition of Poplar fluff sample was n-dimensional acceleratory Avrami–Erofeev model (An) for three-step consecutive reaction mechanism. Governed reaction pathway in pyrolysis process represents fragmentation reactions which arise from levoglucosan decomposing that permits permanent gases and refractory tars, where diffusion-controlled process is involved in the sample devolatilization. The modulated and multiple-step predictions of pyrolysis process were also carried out.