Abstract
Co-upcycling of mixed plastics offers a viable approach to reusing carbon resources in plastic wastes and realizing circular economy. However, the presence of polyvinyl chloride (PVC) often complicates the co-upcycling processes, because chlorine (Cl) released from PVC can deactivate catalysts and enter final products. Moreover, existing plastic upcycling processes usually require harsh reaction conditions. Here we present a strategy enabling efficient co-upcycling of PVC and polypropylene (PP) at mild conditions. We use chlorine-resistant ionic liquids butylpyridinium chloride-aluminium chloride to dechlorinate PVC and simultaneously depolymerize the PP–PVC mixture into Cl-free liquid hydrocarbons, with the co-production of hydrogen chloride (HCl) as byproduct. This conversion approach operates at room temperature without the use of external hydrogen or noble metal catalysts. The Cl-free liquid hydrocarbon yield is up to 97.4 wt% of C and H in the feed PP–PVC mixture. This work can incentivize further technical development in plastic upcycling and improve the sustainability of plastic waste management.
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Data availability
The data that support the findings of this study are available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgements
This work is financially supported by the Natural Science Foundation of Shanghai (23ZR1418800) and National Natural Science Foundation of China (22302069, 22472059). Z.G. acknowledges the Fundamental Research Funds for the Central Universities (YBNL TS2023-07). We appreciate the help of East China Normal University Multifunctional Platform for Innovation for support of SEM characterizations (004).
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W.Z. and Y.L. conceived the research. Z.G., Y.W., L.Y., X.S., Y.S., M.Z. and S.F. performed most of the experiments. Z.G., Y.W., W.Z. and Y.L. analysed results. J.J. collected and analysed NMR spectra. The paper was written and revised by all the authors together.
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Nature Sustainability thanks Jinwen Zhang, George Huber and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Gao, Z., Wang, Y., Yuan, L. et al. Room-temperature co-upcycling of polyvinyl chloride and polypropylene. Nat Sustain 7, 1691–1698 (2024). https://doi.org/10.1038/s41893-024-01468-7
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DOI: https://doi.org/10.1038/s41893-024-01468-7
