Viable Recycling of Polystyrene via Hydrothermal Liquefaction and Pyrolysis

Chemical recycling is considered one of the most sustainable solutions to limit environmental issues related plastic waste pollution, whereby converted into more valuable compounds when mechanical not feasible. Among critical fast-growing components municipal solid waste, polystyrene represents 1/3 filling materials in landfills. In this work, chemical via two main thermochemical processes investigated: pyrolysis and hydrothermal liquefaction (HTL). The influence temperature (HTL: 300–360 °C pyrolysis: 400–600 °C) reaction time 1–4 h; 30 min) on products obtained was studied. liquid were analyzed by using gas chromatography-mass spectrometry (GC-MS), an elemental analysis (EA), Fourier-transform infrared spectroscopy (FT-IR) a thermogravimetric (TGA). During HTL, 360 4 h needed completely decompose mainly oil (83%) water-soluble (10%). former composed aromatics while water phase oxygenated (benzaldehyde acetophenone). led formation 45% 55% at 500 °C, 40% styrene. Pyrolysis thus selective towards recovery styrene monomer HTL can be effective process produce renewable aromatics.