One-Pot Conversion of Polyester and Carbonate into Formate without External H₂

Area of Science:

• Chemical Engineering
• Materials Science
• Environmental Chemistry

Background:

• Plastic waste and CO2 emissions pose significant environmental challenges.
• Upcycling waste materials into value-added products is crucial for a circular economy.

Purpose of the Study:

• To develop an efficient one-pot catalytic process for coconverting plastic waste and CO2 into sodium formate.
• To demonstrate a sustainable method for waste valorization and carbon capture utilization.

Main Methods:

• A two-step catalytic process using a palladium on carbon (Pd/C) catalyst.
• Aqueous-phase reforming of polyesters with water, followed by hydrogenation of sodium bicarbonate (NaHCO3) using in-situ generated hydrogen.
• Utilizing CO2 captured via sodium hydroxide (NaOH) solution to form sodium carbonate (Na2CO3).

Main Results:

• Achieved a high yield of 79% for sodium formate production.
• Successfully transformed various polyesters, including poly(glycolic acid), poly(ethylene terephthalate) (PET), and poly(butylene-adipate-co-terephthalate) (PBAT).
• Demonstrated the process works with commercial biodegradable plastic bags.

Conclusions:

• The developed catalytic process offers a sustainable route for plastic waste upcycling and CO2 utilization.
• This method eliminates the need for external hydrogen or reactive reagents, enhancing its practicality.
• Presents a novel "trash into treasure" pathway for waste valorization.