This article provides a comprehensive review of the theoretical insights into the chemical recycling of polyethylene terephthalate (PET), focusing on the mechanisms and kinetics of various recycling methods. PET is one of the most commonly used plastics, and while mechanical recycling is prevalent, chemical recycling methods such as glycolysis, aminolysis, hydrolysis, and alcoholysis offer more effective alternatives. The paper emphasizes the importance of understanding the reaction mechanisms and kinetics of these methods to improve their efficiency and suitability for a circular economy. Glycolysis is highlighted as the most promising chemical recycling method due to its ability to produce high yields of bis(2-hydroxyethyl) terephthalate (BHET), a key monomer for PET production. The process can be enhanced by using heterogeneous catalysts with large surface areas, which improve reaction kinetics and allow for easy separation and reusability. Advanced heating modes, such as microwave-assisted techniques, also play a significant role in improving the efficiency of glycolysis. The review also discusses the reaction mechanisms of PET degradation, including uncatalyzed and catalyzed processes. It highlights the importance of catalysts, such as Lewis acids and bases, in facilitating the degradation process and the synergic effects that can be achieved through the interaction of different catalytic components. Additionally, the article explores the kinetics of PET degradation, comparing models like the shrinking core model and the bulk model, and discusses how factors such as temperature, pressure, and catalysts influence the reaction rates. The paper concludes that while significant progress has been made in PET chemical recycling, further research is needed to optimize the processes for industrial scalability and economic feasibility. It recommends focusing on the development of novel heterogeneous catalysts and advanced heating techniques to enhance the efficiency and sustainability of PET recycling. The study provides valuable insights for future research and development in the field of PET chemical recycling, aiming to support the transition towards a more sustainable and circular economy.This article provides a comprehensive review of the theoretical insights into the chemical recycling of polyethylene terephthalate (PET), focusing on the mechanisms and kinetics of various recycling methods. PET is one of the most commonly used plastics, and while mechanical recycling is prevalent, chemical recycling methods such as glycolysis, aminolysis, hydrolysis, and alcoholysis offer more effective alternatives. The paper emphasizes the importance of understanding the reaction mechanisms and kinetics of these methods to improve their efficiency and suitability for a circular economy. Glycolysis is highlighted as the most promising chemical recycling method due to its ability to produce high yields of bis(2-hydroxyethyl) terephthalate (BHET), a key monomer for PET production. The process can be enhanced by using heterogeneous catalysts with large surface areas, which improve reaction kinetics and allow for easy separation and reusability. Advanced heating modes, such as microwave-assisted techniques, also play a significant role in improving the efficiency of glycolysis. The review also discusses the reaction mechanisms of PET degradation, including uncatalyzed and catalyzed processes. It highlights the importance of catalysts, such as Lewis acids and bases, in facilitating the degradation process and the synergic effects that can be achieved through the interaction of different catalytic components. Additionally, the article explores the kinetics of PET degradation, comparing models like the shrinking core model and the bulk model, and discusses how factors such as temperature, pressure, and catalysts influence the reaction rates. The paper concludes that while significant progress has been made in PET chemical recycling, further research is needed to optimize the processes for industrial scalability and economic feasibility. It recommends focusing on the development of novel heterogeneous catalysts and advanced heating techniques to enhance the efficiency and sustainability of PET recycling. The study provides valuable insights for future research and development in the field of PET chemical recycling, aiming to support the transition towards a more sustainable and circular economy.