(Invited) Enhancing PET Plastic Circularity and Decarbonization through Process Electrification and Intensification

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Polyethylene terephthalate (PET) production generates roughly 3.2 kg of CO2 per kg of resin.[1] As the most produced plastic globally (82 million metric tons per year), PET contributes to 272 million metric tons of CO2 equivalent annually. Chemical depolymerization of PET into its monomers is a key strategy for achieving plastic circularity. While various methods have emerged in recent decades, current chemical recycling processes are often uneconomical and do not significantly reduce greenhouse gas emissions. For instance, catalytic depolymerization using base catalysts (e.g., NaOH) in alcohols is being commercialized, but NaOH is neither a superior catalyst nor cost-effective due to its production and delivery expenses. Consequently, the high cost leads to PET waste ending up in landfills or incinerators, perpetuating low circularity and high CO2 emissions.[2,3]To address these limitations in chemical PET depolymerization, our team has developed an innovative electrochemical system for efficient and cost-effective PET recycling. This system selectively decomposes mixed plastic waste at room temperature and ambient pressure, achieving rapid depolymerization into virgin-quality PET monomers. The process is intensified through electrification, significantly reducing overall costs and CO2 emissions while promoting PET circularity. By incorporating renewable electricity, the system can utilize excess energy generated during off-peak hours. Additionally, the process co-produces valuable chemicals like hydrogen and hydrochloric acid (HCl), ultimately making PET recycling economically viable. We are committed to further maturing this electrochemical PET depolymerization technology with the goal of commercialization.