Contribution of plastic solid components to volatile organic compounds formation during plastics combustion

Area of Science:

• Environmental Chemistry
• Polymer Science
• Combustion Science

Background:

• Plastic waste combustion generates harmful volatile organic compounds (VOCs).
• Micro-mechanisms of VOC formation during plastic combustion are not well understood.

Purpose of the Study:

• To investigate the relationship between VOC formation and solid component degradation during plastic combustion.
• To elucidate the formation pathways and characteristics of VOCs released from different plastic types.

Main Methods:

• Analysis of VOCs released during the combustion of various plastics.
• Characterization of VOCs based on carbon content, volatility, and oxidation degree.
• Comparison of VOC profiles from polyethylene terephthalate (PET), poly(butylene adipate-co-terephthalate) (PBAT), polyethylene (PE), and polypropylene (PP).

Main Results:

• VOCs released have low carbon content, medium volatility, and medium oxidation degree.
• Ketones, aldehydes, and acids are dominant VOCs, originating from polymer depolymerization and oxidation.
• PET and PBAT combustion yield more aromatics than PE and PP, with a delayed temperature response for aromatics from PET/PBAT.

Conclusions:

• VOC formation during plastic combustion is closely tied to solid component degradation.
• Similar chemical structures of PET and PBAT lead to comparable VOC formation mechanisms.
• Understanding these mechanisms aids in controlling contaminants from plastic combustion.