Towards selective recycling technologies for complex plastic waste

Abstract

Despite the growing volume of plastic waste, plastic recycling remains limited, hindered by a complex interplay of economic, societal and logistical challenges. Technical barriers persist, particularly in scaling laboratory innovations to industrially viable processes. Moreover, the research focus on idealized, single-polymer waste streams overlooks the complexity of real-world plastic waste streams, which are typically heterogeneous and contaminated. The development of strategies for the selective recycling of materials from complex waste streams is crucial to advancing a circular plastics economy. In this Review, we define the concept of complex plastic waste and assess recycling strategies that show potential for the selective recycling of plastic waste, namely, solvent-based recycling and depolymerization technologies. By classifying approaches according to application and evaluating their scalability and operational reliability, we identify key limitations and outline future directions for the selective and efficient recycling of industrially relevant plastic mixtures. Technologies for the selective recycling of heterogeneous and contaminated plastic waste streams are required to achieve a circular plastics economy. This Review surveys solvent-based recycling and depolymerization strategies towards the selective recycling of key types of plastic waste.