Exploring Synergistic Interactions between Polystyrene and Polyethylene.

Abstract

An attempt was undertaken to elevate production of aromatic compounds through co-upcycling of polystyrene (PS) and low-density polyethylene (LDPE). The plastics samples were upcycled at 400 °C with catalyst H-ZSM-5. Compared to single plastic upcycling, co-upcycling PS and LDPE demonstrated high advantages: lowered reaction temperature (390 °C), medium reaction rate (-1.35 %/°C), low yield to coke (1.62 % or less) and enhanced aromatics yield (42.9-43.5 %). In-situ FTIR results demonstrated a constant production of aromatics in the 1 : 1 mixed plastic while in pure plastics, aromatic production quickly dropped. Compared to single PS upcycling, co-upcycling PS with PE produced more monocyclic aromatic hydrocarbons (MAHs) at close to 43.0 % versus 32.5 % and less polycyclic aromatic hydrocarbons (PAHs) at 16.8-34.6 % versus 49.5 %. From these data, the synergy between PS and LDPE were confirmed and the mechanism in which they increased MAHs production was proposed.