Aqueous Upcycling of Polyethylene Furanoate From Mixed Plastic Feeds Into Metal‐Organic Frameworks

Mixed and contaminated plastic waste is the dominant obstacle to plastics' circularity because most recycling or upcycling technologies require clean, pre-sorted feedstocks. Here, we demonstrate a sorting-free upcycling method with purification embedded in upcycling. Polyethylene furanoate (PEF), an emerging biomass-derived polyester, is converted in water into the valuable metal-organic framework (MOF) MIL-160 in high yield. This method remains effective when using unsorted polymer mixtures, including mixtures containing competing polyesters such as polyethylene terephthalate (PET) and polylactic acid (PLA), yielding a pure MOF with no loss in sorption performance. To address the MOF's own end-of-life, we demonstrate the ease of recovering 2,5-furan-dicarboxylic acid (FDCA) from MIL-160 for recycling and redeployment to produce other MOFs such as CAU-28. This connects plastic upcycling to MOF end-of-life management, showing that the upcycled product is not a dead-end material but a reversible reservoir of FDCA that can be recovered and recirculated. Life cycle assessment showed that producing MIL-160 from mixed PET/PEF plastic feedstock results in a 31% reduction in life-cycle global warming potential compared to using biomass directly. Additionally, techno-economic analysis supported the economic feasibility of producing MIL-160 from mixed PET/PEF. Valorizing PEF into MOFs with diverse applications offers viable end-of-life solutions for these bioplastics.