Polylactic Acid Production from Agricultural Biomass and Waste Feedstocks: A Comparative Evaluation of Environmental Impact

Polylactic acid, a biodegradable biopolymer derived from renewable resources, is increasingly recognized as a sustainable alternative to conventional petroleum-based plastics that have contributed to toxic environmental pollution worldwide. Yet, various pathways to produce polylactic acid may differ in their environmental footprint and resource demands. In this study, we evaluate life cycle assessment data to compare polylactic acid production through six different routes: three from agricultural biomass feedstocks, and three from waste feedstocks, focusing on three sustainability parameters, including carbon intensity, energy intensity, and material intensity. The major findings show lower carbon emission intensity due to lower energy and material intensities that are required for producing polylactic acid from waste feedstocks than from agricultural biomass feedstocks. This research highlights the importance of optimizing polylactic acid production processes to minimize energy and material use for reduced carbon emissions and thereby maximize the sustainability value of this alternative polymeric material. Future research should focus on process innovations to further reduce carbon emissions.