聚对苯二甲酸乙二醇酯(PET),最普遍的工程塑料之一,为碳中和和循环经济带来了环境挑战和机遇。这篇综述全面阐述了生物和非生物方法在PET回收/再循环方面的最新进展。生物方面,PET的微生物解聚,随着再生单体[对苯二甲酸(TPA)的生物合成,乙二醇(EG)]到增值产品,提出了一种管理PET废物的替代方法,可以减少CO2。生物学上,热处理(即,水解,糖酵解,甲醇分解,等。)和光/电催化,通过催化进步,可以解聚或转化PET/PET单体更灵活,简单,快,可控的方式。串联非生物/生物催化为PET再循环产生商品化学品和替代材料提供了巨大的潜力,理想情况下,在较低的能量输入下,温室气体排放,和成本,与原始聚合物制造相比。值得注意的是,超过25种升级的PET产品(例如,己二酸,粘康酸,儿茶酚,香兰素,和乙醇酸,等。)已经确定,强调了PET在不同应用中的升级潜力。可以努力开发PET的化学催化解聚,改善PET的微生物解聚(例如,水解效率,酶活性,热和pH水平稳定性,等。),以及通过计算和机器学习算法鉴定能够降解PET的新微生物或水解酶。因此,这篇综述为推进PET回收和再循环技术提供了路线图,它们具有塑造PET废物管理未来的潜力,并有助于保护我们的生态系统。
Polyethylene terephthalate (PET), one of the most ubiquitous engineering plastics, presents both environmental challenges and opportunities for carbon neutrality and a circular economy. This review comprehensively addressed the latest developments in biotic and abiotic approaches for PET recycling/upcycling. Biotically, microbial depolymerization of PET, along with the biosynthesis of reclaimed
monomers [terephthalic acid (TPA), ethylene glycol (EG)] to value-added products, presents an alternative for managing PET waste and enables CO2 reduction. Abiotically, thermal treatments (i.e., hydrolysis, glycolysis, methanolysis, etc.) and photo/electrocatalysis, enabled by catalysis advances, can depolymerize or convert PET/PET
monomers in a more flexible, simple, fast, and controllable manner. Tandem abiotic/biotic catalysis offers great potential for PET upcycling to generate commodity chemicals and alternative materials, ideally at lower energy inputs, greenhouse gas emissions, and costs, compared to virgin polymer fabrication. Remarkably, over 25 types of upgraded PET products (e.g., adipic acid, muconic acid, catechol, vanillin, and glycolic acid, etc.) have been identified, underscoring the potential of PET upcycling in diverse applications. Efforts can be made to develop chemo-catalytic depolymerization of PET, improve microbial depolymerization of PET (e.g., hydrolysis efficiency, enzymatic activity, thermal and pH level stability, etc.), as well as identify new microorganisms or hydrolases capable of degrading PET through computational and machine learning algorithms. Consequently, this review provides a roadmap for advancing PET recycling and upcycling technologies, which hold the potential to shape the future of PET waste management and contribute to the preservation of our ecosystems.