Thermogravimetric analysis and kinetic study of marine plastic litter

Abstract

This paper deals with marine plastic debris and its collection and recycling methods as one possible answer to the rising amount of plastic in marine environments. A novel approach is to use energy recovery, for example pyrolysis of marine plastic debris into high-energy products. Compared to other thermal processes, pyrolysis requires less technical effort and the end products can be stored or directly reused. In order to design such an onboard pyrolysis reactor, it is necessary to know more facts about the feedstock, especially the thermochemical behaviour and kinetic parameters. Therefore, a thermogravimetric analysis was carried out for three selected plastic sizes with a temperature range of 34-1000 °C. The results obtained from TGA showed the same curve shape for all samples: single stage degradation in the temperature region of 700-780 K with most of the total weight loss (95%). Small microplastics had an average activation energy of 320-325 kJ/mol.

Keywords: Kinetics; Marine litter; Pyrolysis; TGA.