A Pathway\nAnalysis Framework for Evaluating the Economic\nand Environmental Viability of Biomass-Based Plastic Production

Plastic production from fossil feedstocks (e.g., naphtha,\ncoal,\nand natural gas) is not sustainable and causes known environmental\nimpacts such as global warming. A possible solution is to shift production\npathways to use biomass, which is a sustainable feedstock that can\nsequester atmospheric carbon dioxide. This study presents an optimization-based\npathway analysis framework for evaluating the carbon footprints of\nthe production of mainstream plastics from biomass and fossil feedstocks.\nWe use the modeling framework to quickly navigate complex interdependencies\nthat exist between the production pathways of different plastics and\nto determine pathways of minimum production cost under a range of\ncarbon pricing scenarios. The framework interprets carbon prices as\nan exogenous taxation scheme or an endogenous negative value perceived\nby producers. The proposed approach reveals the biomass feedstock\nquantities needed to displace fossil counterparts and the plastics\nand technologies that should be prioritized. The framework can also\nbe used for evaluating system-wide trade-offs between production costs\nand carbon footprints that arise from pathway interdependencies. We\nalso evaluate hidden environmental impacts associated with the large-scale\nuse of biomass as a feedstock, such as land use and water eutrophication\nthat results from a significant increase in fertilizer use. Therefore,\nit is important to highlight that there are trade-offs between decarbonization\nand other environmental issues. The proposed framework provides an\nintegrative platform for basic techno-economic and life-cycle data\nthat can be used for analyzing diverse scenarios and determining necessary\ntechnology targets (e.g., yields, footprints, and costs) to achieve\nrequired levels of decarbonization.