Energy & Fuels, Vol.33, No.12, 12666-12678, 2019
Pyrolysis of Expanded Waste Polystyrene: Influence of Nickel-Doped Copper Oxide on Kinetics, Thermodynamics, and Product Distribution
In this study, pyrolysis of waste polystyrene was investigated in the presence of a mixed metal oxide (Nix=0.5Cu1-xO) under inert conditions in a pyrolysis chamber. The pyrolysis products were collected and analyzed by gas chromatography/mass spectrometry. Kinetic parameters were determined from thermogravimetric data, and the activation energy and pre-exponential factor at maximum conversion were found to be in the range of 120-134 kJ mol(-1) and 1.5 X 10(9)-2.1 X 10(10t) respectively, using the Kissinger-Akahira-Sunose (KAS), Ozawa-Flynn-Wall, Friedman, and Coats-Redfern models. The results demonstrated that the KAS method is the most suitable model for the determination of kinetic parameters. Therefore, thermodynamic parameters were determined with reference to the same model. Thermodynamic parameters, such as enthalpy, entropy, and Gibbs free energy, were investigated and found to be in the range of 88.79-113.98 kJ mol(-1), 137.12 to 36.96 J mol(-1), and 125.29-137.96 kJ mol(-1), respectively. By comparing the pyrolysis products and kinetic parameters of catalytic degradation with those of noncatalytic degradation, a predictable increase in pyrolysis products and decrease in activation energy at maximum conversion were observed.