Enzymatic Recycling Revolutions

The widespread use of polyethylene terephthalate (PET), combined with its resistance to natural degradation, has made it a major contributor to global plastic pollution. Conventional recycling approaches, including mechanical and chemical methods, have struggled to address this issue effectively due to limitations such as quality degradation, high energy demands, and environmental concerns. Enzymatic recycling has emerged as a promising alternative, leveraging biological catalysts to selectively depolymerize plastics into reusable monomers under milder conditions. This method offers unique advantages, including high specificity, reduced energy consumption, minimal secondary pollution, and alignment with circular economic principles. This chapter provides a comprehensive overview of enzymatic recycling, elucidating the mechanisms of enzymatic depolymerization and its distinct benefits over traditional methods. The technological, economic, and scalability challenges hindering widespread adoption are critically assessed. In addition, recent advances in enzyme engineering, process optimization, and synergistic enzyme systems are highlighted, with their potential to enhance efficiency and broaden substrate applicability being underscored. By comparing enzymatic recycling with conventional recycling routes, its role as a sustainable and economically viable solution for PET and other polymers is emphasized. Looking ahead, research is expected to be directed toward the development of robust, highly active enzymes suitable for industrial-scale operations, the creation of cost-effective bioprocesses, and the integration of enzymatic recycling into existing waste management systems. Through this approach, the closing of the loop in plastic lifecycles is facilitated, and enzymatic recycling is positioned as a critical component in global efforts toward sustainable plastic waste management and the adoption of a circular economy.