Literature Review on the Recycling Postconsumer Plastic Waste from Pyrolysis

Environmental problems associated with postconsumer plastic waste are numerous and are expected to worsen due to the increasing volume of waste generated. Currently, in the European Union, only 35% of plastic waste is recycled, which implies that plastic waste treatment is mostly focused on incineration and landfilling, which are less priority options than recycling according to the waste hierarchy. In order to increase the recycled plastic rate, chemical recycling technologies for plastic waste have been considered as a complement to mechanical recycling, which is currently the most widely used technology. The chemical recycling idea presented in this work is based on the pyrolysis of plastic waste, which is one of the most interesting chemical recycling processes. This paper presents a chemical recycling technology for postconsumer plastic waste (polyolefins and polystyrene with an approximate ratio of 2,6) based on the pyrolysis process and subsequent cascade processes, such as the catalytic reforming of the naphtha obtained through pyrolysis. The objective of the presented technology is to maximize the production of aromatic compounds, benzene, toluene, and xylene, which will close the circle of materials by being precursors of recycled plastics of comparable quality to virgin. This work also considers the Life Cycle Assessment (LCA) of plastic waste pyrolysis and the advantages and challenges of the described technology.