Sustainable Chemical Recycling of PET: Promise and Challenges of Microwave-Assisted Solvolysis

Polyethylene terephthalate (PET) is a common plastic widely used in food packaging, especially plastic bottles, and in fibers and textiles. The widespread use of PET and its intentional and unintentional release and disposal over the past few decades have placed significant pressure on the environment, necessitating the development of green, low-cost, and efficient recycling technologies to mitigate this impact. This article reviews recent advances in microwave-assisted catalytic depolymerization of PET. It begins by outlining the fundamental principles of PET materials science and depolymerization mechanisms. The article then reviews the historical evolution of this research and presents a benchmark comparison of different depolymerization methodologies. Finally, through a critical analysis and comparison of state-of-the-art approaches, the article identifies emerging trends and highlights promising directions for future research in the field. A comprehensive comparison of conventional and microwave heating methods is presented, indicating that catalyst-assisted microwave systems can shorten reaction times and achieve high product yields under optimized conditions. Key advantages and limitations are highlighted, and persistent challenges are discussed. Overall, this article surveys the latest progress in the chemical recycling of PET and provides critical insights for future research and further development of microwave-assisted catalytic PET depolymerization technology.