(510s) Optimizing Chemical Recycling of Waste PET/Polyolefin Streams through Agile Life Cycle Assessment (LCA)

Restorative and sustainable future of the petrochemical resources calls for a circular economy of plastics. Conventional end-of-life treatments of plastics require either huge land area for landfilling or produces noxious and harmful gases via incineration. To exploit the full potential of the waste plastics, plastic to fuel upcycling path is a solution to this challenge. PET and PP have myriad of applications, mostly in making containers, packaging, and clothing. LCA can be used to identify the best environmentally sustainable plastic waste management option(s). In this study, we present a multidisciplinary modeling framework that integrates kinetic model, process design, and LCA to evaluate the performance, energy demand, and environmental implications of plastic upcycling pathways. The experiments and microkinetic modeling that investigates the interaction effects in mixed plastic pyrolysis is leveraged and the results on yields, molecular weight ranges, and kinetics is used to inform the LCA parameters. Further, by linking technical performance metrics through mechanistic modeling, predictive design decisions can be implemented to optimize the process on both energy use and carbon emissions of recycling a mixture of PET and PP waste feedstocks. The impacts of individual process and decision variables on overall systems level sustainability can also be characterized.