Research progress in catalytic recycling of polyethylene terephthalate
ZHANG Shengbo
YAN Chuxiao
Abstract：Significance Plastics are widely used across various sectors,including food packaging,textiles,construction,and healthcare,owing to their cost-effectiveness,lightweight properties,and remarkable chemical stability.However,due to their slow degrada-tion rates,plastics tend to accumulate on land or be transported into the ocean,posing severe environmental threats.Traditional plastic waste disposal methods,primarily landfilling and incineration,are criticized for occupying vast land areas and emitting toxic gases.In comparison,plastic recycling offers a more sustainable approach by breaking down waste plastics into monomers and converting them into high-value chemicals,supporting the circular economy.Among plastics,polyethylene terephthalate(PET),a polyester synthesized from terephthalic acid(TPA)and ethylene glycol(EG),stands out for its thermal stability,transparency,and lightweight properties,making it ideal for beverage bottles and textiles.However,PET recycling rates fall far behind their production rates.Moreover,existing PET recycling methods are mostly energy-intensive and prone to generate sec-ondary pollutants,toxic byproducts,and harmful gases.Pyrolysis-based PET recycling further exacerbates these issues by pro-ducing formaldehyde,greenhouse gases,and polycyclic aromatic hydrocarbons.These byproducts reduce thermal energy utiliza-tion efficiency and intensify the greenhouse effect,posing further risks to the ecological environment and human health.
Progress This article focuses on chemical recycling methods for PET,with particular emphasis on techniques such as glycoly-sis,alcoholysis,and hydrolysis.The reaction mechanisms and catalysts used in each method are systematically elucidated,and the latest advancements in glycolysis and hydrolysis methods are summarized.In addition,this article explores bioremediation approaches for PET recycling,examining the reaction activity and underlying mechanism of enzyme-catalyzed PET hydrolysis under mild conditions.Key enzymes such as keratinase and PETase are discussed as examples,and cutting-edge technologies in enzyme-catalyzed PET recycling are introduced.The biological recycling of PET offers the following advantages.It operates under mild reaction conditions,without the need for high temperatures and pressures or additional alcohol/acid-base reagents.The degradation products can be transformed into high-value chemicals.Compared to chemical recycling,biological recycling not only reduces costs but also minimizes secondary environmental pollution.These benefits show its broad application prospects and significant research value.
Conclusions and Prospects The development of green PET recycling technologies has become an urgent priority due to their sig-nificance for environmental protection and sustainable development.Both chemical and biochemical PET degradation methods offer significant advantages,including energy efficiency,environmental friendliness,and the ability to convert waste into mono-mers as chemical raw materials for secondary utilization.Therefore,chemical and biological recycling are promising research directions in sustainable materials management.Future studies on catalytic PET recycling and upgrading should focus on opti-mizing catalytic systems,elucidating reaction mechanisms,developing efficient reaction processes under mild conditions,and enhancing product value and applications.Moreover,technical and economic analyses and life cycle assessments should be inte-grated throughout the entire research process to comprehensively evaluate the feasibility and sustainability of new catalytic sys-tems,thereby ensuring their economic viability and environmental friendliness in practical applications.
Keywords：polyethylene terephthalateglycolysishydrolysisbiological recyclingchemical recycling
Publication Date：2026-03-01
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：15( 134-148 )