Investigating Sustainable Recycling Methods for Common Plastic: A Focus on PET

Title: Assessment of PET Depolymerization Processes for Circular Economy. 2. Process Design Options and Process Modeling Evaluation for Methanolysis, Glycolysis, and Hydrolysis

In this recent publication, researchers have undertaken a detailed examination of Poly(ethylene terephthalate) (PET), the widely used thermoplastic found in items like drink bottles, packaging, and textiles. The study emphasizes chemical depolymerization as a robust recycling method capable of handling low-quality and impure waste PET sources.

The research systematically evaluates three primary routes for PET depolymerization: methanolysis, glycolysis, and hydrolysis. By leveraging a combination of industrial patent literature and process design expertise, the team simulates comprehensive depolymerization processes. The findings illuminate how different configurations and process variables impact efficiency.

Among the three methods, glycolysis is identified as the simplest and least energy-intensive process, particularly when dealing with easily purifiable PET. Methanolysis proves practical for scenarios where purification becomes more challenging. However, hydrolysis stands out as the most complex and energy-intensive process fundamentally.

The researchers reasonably anticipate that a PET depolymerization process could effectively convert PET into monomers with an energy demand ranging between 6000 and 10,000 kJ/kg of PET. This insight offers a step towards sustainable plastic recycling, addressing the challenges posed by the varied quality of waste PET sources.

SOURCE: pubs.acs.org