Repurposing polyethylene terephthalate plastic waste to capture carbon dioxide

Area of Science:

• Polymer Chemistry
• Materials Science
• Environmental Science

Background:

• Polyethylene terephthalate (PET) is a widely used plastic with limited sustainable waste management options.
• Current PET disposal methods include mechanical recycling, incineration, and landfilling, which have environmental drawbacks.

Purpose of the Study:

• To develop a chemical upcycling strategy for PET waste.
• To create novel materials for carbon dioxide (CO2) capture from the resulting upcycled products.

Main Methods:

• Aminolysis of PET waste to produce bis-aminoamide (BAETA) and oligomers.
• Characterization of the CO2 capture performance of the synthesized materials.
• Testing material stability and reusability under various conditions.

Main Results:

• The aminolysis products, particularly BAETA, exhibit significant CO2 capture capacity (up to 3.4 mol/kg).
• The material demonstrates high selectivity for CO2 capture from flue gas and ambient air, even under humid conditions.
• The synthesized material is thermally stable (>250°C) and effective for CO2 capture at elevated temperatures (up to 170°C) over multiple cycles.
• Scalable production was confirmed using 1 kg of untreated consumer PET waste.

Conclusions:

• Chemical upcycling of PET waste via aminolysis offers a viable route to high-performance CO2 capture materials.
• This approach provides a sustainable solution for both plastic waste management and carbon dioxide mitigation.
• The developed technology presents a potential pathway towards achieving net-negative emissions.