Are Reliable and Emerging Technologies Available for Plastic Recycling in a Circular Economy?

A spectrum of plastics has been produced in the last 70 years, and plastic production has increased faster than any other manufactured material. Current recycling of all plastic materials is pegged at 10% or less. The social value that plastics enjoys is reflected in its myriad uses for engineered durability to single-use applications. Disposable or single-use plastic items have become a significant problem. Plastic debris has become ubiquitous to the landscape and aquatic resources, leading to human health, ecological concerns, and sustainability issues. Past disposal practices relied on waste plastic flows to certain countries for disposal, but these have been summarily curtailed, needing alternatives as productive and environmentally conscious recycling technology. Waste plastics can be repurposed using purification, decomposition, or conversion processes that are based on established and emerging mechanical and chemical technologies. Plastic recycling technologies, such as thermal, chemical, and biological depolymerization processes, including pyrolytic technologies using plastics-to-fuel strategies, are under development ranging from bench-scale demonstrations to full-scale implementation. The ideal of closed supply chain constraints offers optimal solutions to plastic recycling. Evaluation of new processes requires performance assessment to understand better how plastics recycling technologies contribute to the environment and the sustainable reuse of plastic materials.