Prevention of chlorinated hydrocarbons formation during pyrolysis of PVC or PVDC mixed plastics

Pyrolysis of poly(vinyl chloride) (PVC) and poly(vinylidene chloride) (PVDC) mixed with poly(ethylene) (PE), poly(propylene) (PP), poly(styrene) (PS) [PE/PP/PS/PVC, and PE/PP/PS/PVDC (3 ∶ 3 ∶ 3 ∶ 1)] were performed with a controlled temperature program (step I: room temperature to 330 °C; kept at 330 °C (for PVC), 300 °C (for PVDC) for 2 h; step II: 300 or 330 °C to final temperature 430 °C) and produced the chlorine free hydrocarbons in the absence of dechlorination catalyst/sorbent, which can be used as a chemical feedstock in a refinery. The temperature programs were selected based on the TGA analysis of individual plastic samples.