Kinetic and thermodynamic analyses of co-pyrolysis of pine wood and polyethylene plastic based on Fraser-Suzuki deconvolution procedure

Co-pyrolysis of biomass and plastics is a promising way to produce high-quality liquid fuel, and the knowledge on its kinetic and thermodynamic behaviors is crucial for designing an efficient reactor system. In this study, kinetic triplets and major thermodynamic parameters of both non-catalytic and catalytic co-pyrolysis of pine wood and high-density polyethylene (HDPE) were evaluated. Due to the complexity of co-pyrolysis process, Fraser-Suzuki function was adopted to deconvolute the derivative thermogravimetric (DTG) curves into four pseudocomponents; namely pseudo- cellulose, hemicellulose, lignin and HDPE. For non-catalytic co-pyrolysis, average apparent activation energy of pseudo-hemicellulose, cellulose, lignin and HDPE were 137.12, 166.81, 227.2, 246.56 kJ/mol, respectively. The presence of HZSM-5 decreased both activation energy and preexponential factor and affected reaction mechanisms of each component. The activation energy of HDPE decreased by about 35% after addition of catalyst. The thermodynamic analyses revealed that external energy was required for all components to form activated complex, and this process was favored by addition of catalyst HZSM-5. Results obtained in this work are expected to provide more precise fundamental information for further scale-up of co-pyrolysis process.

Automated summary

This study evaluated the kinetic and thermodynamic parameters of non-catalytic and catalytic co-pyrolysis of pine wood and HDPE, using Fraser-Suzuki function for deconvolution. The presence of catalyst HZSM-5 decreased activation energy and preexponential factor and affected reaction mechanisms of each component.