Valorization of Plastic Waste via Advanced Separation and Processing

With an overarching goal the reduction in the amount of plastic waste that ends up in landfills or incinerators and the increase in the amount of post-consumer plastic in various products, we research the: (1) automated sorting of mixed plastic waste, and (2) valorization of recovered plastic; this with support from NSF award 2029375 (EFRI E3P). This paper highlights results from this collaborative team effort. High-throughput, real-time, stand-off detection of different types of plastics is advanced through the combination of novel sensor technology, spectral and image databases, and machine learning. Upcycling of sorted polyolefins is achieved through: (i) selective dissolution/precipitation in environmentally responsible solvents to recover the target type of plastic, suitable for reuse in new products, and (ii) tailored chemical modification of polyolefins to produce functional waxes that can serve as building blocks for high- value materials. The fundamental and applied knowledge generated in this project addresses the grand challenge of significantly increasing the global plastic recycling rates. This challenge is tackled here in a manner that is environmentally responsible, technically feasible, economically competitive, and societally beneficial.