Upcycling of Contaminated Plastics Recovered Through Landfill Mining and Pyrolysis to High-Value Products

Pyrolysis is known for yielding condensable volatile organic vapours of varying chain length and complexity depending on process configuration and operating conditions. Although the process has been known for decades, significant challenges need to be addressed in order to deploy economic commercial systems. Given that plastics are manufactured from fossil feedstock, the properties of the pyrolysis liquids are expected to be similar to those of conventional chemicals and fuels. However, the wide range of non-standardised mixed waste plastics and presence of organic additives enhance secondary reactions during thermal conversion processes. While these issues need to be addressed in conventional processes of valorisation of plastics, more uncertainties and challenges are encountered in the case of advanced thermal conversion of plastics recovered through landfill mining because the presence of contaminants and chemical degradation result in more variability of the composition.