Abstract
With the large volume of consumer plastic waste generated worldwide, one common problem in the Philippines involves the disposal and treatment of solid wastes. Current processes in the disposal of post- consumer plastic wastes such as incineration or landfill are not fully acceptable based on international standards. As such, there is an urgent need for a practical, safe and efficient disposal method which can also convert waste into useful energy. Pyrolysis and gasification are very well-known thermal degradation processes that convert carbonaceous materials into useful gaseous products that still contain significant amount of energy. The parameters obtained from the kinetic study of these processes are very essential in the design of useful conversion technologies such as reactors and gasifiers. In this study, the pyrolysis and gasification of plastic waste samples were investigated in a thermogravimetric analyser (TGA).
The kinetic parameters for the pyrolysis of the samples were obtained at heating rates ranging from 10 - 30 K/min. The mean activation energies for the pyrolysis reaction were found to be 124.1 kJ/mol and 107.3 kJ/mol, for samples X and Y. In terms of the temperature at which maximum degradation occurs, the differential thermogravimetric (DTG) curve of the plastic waste sample resembles that of a ternary mixture containing polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET). For the gasification of the plastic waste samples with CO2, a temperature higher than 600 °C is required to attain significant conversion. The activation energies for the gasification of the waste plastic samples were found to be 144.7 and 147.8 kJ/mol for samples X and Y.
