A systematic review of plastic recycling: technology, environmental impact and economic evaluation

In this systematic review, advancements in plastic recycling technologies, including mechanical, thermolysis, chemical and biological methods, are examined. Comparisons among recycling technologies have identified current research trends, including a focus on pretreatment technologies for waste materials and the development of new organic chemistry or biological techniques that enable recycling with minimal energy consumption. Existing environmental and economic studies are also compared. The findings highlight differences in the environmental characteristics of various recycling methods, including their ability to recover plastic resins, carbon footprint, electricity consumption and gas emissions. The comparisons also reveal the challenges associated with these methods: mechanical recycling often encounters economic barriers due to contamination and inefficiencies in sorting and cleaning processes; thermolysis is constrained by high energy demands and operational costs, whereas chemical and biological recycling faces limitations related to scalability and material costs. Additionally, current challenges, emerging research areas and future directions in plastic recycling are discussed. For example, the role of innovative techniques, such as artificial intelligence, in refining recycling processes is emphasized. The importance of incorporating circular economy principles in the integrated sustainable analysis of recycling processes is also highlighted. The innovative contribution of this review is to address both technological developments and their environmental and economic implications. The focus is placed on literature from the past 10 years to ensure coverage of the most recent advancements. Overall, the insights of this review article aim to guide researchers, policymakers and industry stakeholders in improving sustainable management practices for plastic waste.