Abstract
Derived from renewable feedstocks, such as biomass, polylactic acid (PLA) is considered a more environmentally friendly plastic than conventional petroleum-based polyethylene terephthalate (PET). However, PLA must still be recycled, and its growing popularity and mixture with PET plastics at the disposal stage poses a cross-contamination threat in existing recycling facilities and results in low-value and low-quality recycled products. Hybrid upcycling has been proposed as a promising sustainable solution for mixed plastic waste, but its techno-economic and life cycle environmental performance remain understudied. Here we propose a hybrid upcycling approach using a biocompatible ionic liquid (IL) to first chemically depolymerize plastics and then convert the depolymerized stream via biological upgrading with no extra separation. We show that over 95% of mixed PET/PLA was depolymerized into the respective monomers, which then served as the sole carbon source for the growth of Pseudomonas putida, enabling the conversion of the depolymerized plastics into biodegradable polyhydroxyalkanoates (PHAs). In comparison to conventional commercial PHAs, the estimated optimal production cost and carbon footprint are reduced by 62% and 29%, respectively.
| Original language | English |
|---|---|
| Pages (from-to) | 1576-1590 |
| Number of pages | 15 |
| Journal | One Earth |
| Volume | 6 |
| Issue number | 11 |
| DOIs | |
| State | Published - Nov 17 2023 |
| Externally published | Yes |
Funding
The authors would like to acknowledge funding support from X The Moonshot Factory. The Advanced Biofuels and Bioproducts Process Demonstration Unit (ABPDU). They would also like to thank the Bioenergy Technologies Office (BETO) within the United States (US) Department of Energy (DOE)’s Office of Energy Efficiency and Renewable Energy (EERE) for support. Part of this work conducted by the Joint BioEnergy Institute (JBEI) and was supported by the Office of Science, Biological and Environmental Research (BER), of the US DOE under contract DE-AC02-05CH11231. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc. for the US DOE's National Nuclear Security Administration (NNSA) under contract DE-NA0003525. We would like to thank Adam Guss at Oak Ridge National Laboratory for providing Pseudomonas putida TDM461. We would also like to thank Bianca Susara, who helped with the graphical abstract. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the US Government or any agency thereof. Neither the US Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed or represents that its use would not infringe privately owned rights. C.D. H.C. B.A.S. and N.S. conceptualized and designed the work. C.D. H.C. Z.W. M.M. N.R.B. R.A.A. and S.H. implemented the work and prepared and edited the manuscript. A.H. D.R.B. S.S. C.D.S. J.D.K. B.A.S. and N.S. reviewed and edited the overall manuscript. Funding acquisition was led by N.S. J.D.K. and B.A.S. with contributions by D.R.B. C.D. H.C. B.A.S. and N.S. are named inventors on at least one related patent or patent application. J.D.K. has financial interest in Amyris, Lygos, Demetrix, Napigen, Maple Bio, Apertor Labs, Berkeley Yeast, Ansa Biotechnologies, Cyklos Materials, and Zero Acre Farms. C.D.S. has a financial interest in Cyklos Materials. B.A.S. has a financial interest in Erg Bio, Caribou Biofuels, and Illium Technologies. N.R.B. has a financial interest in Erg Bio. We support inclusive, diverse, and equitable conduct of research. The authors would like to acknowledge funding support from X The Moonshot Factory. The Advanced Biofuels and Bioproducts Process Demonstration Unit (ABPDU ). They would also like to thank the Bioenergy Technologies Office (BETO) within the United States (US) Department of Energy (DOE)’s Office of Energy Efficiency and Renewable Energy (EERE) for support. Part of this work conducted by the Joint BioEnergy Institute (JBEI) and was supported by the Office of Science , Biological and Environmental Research (BER) , of the US DOE under contract DE-AC02-05CH11231. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the US DOE’s National Nuclear Security Administration (NNSA) under contract DE-NA0003525. We would like to thank Adam Guss at Oak Ridge National Laboratory for providing Pseudomonas putida TDM461. We would also like to thank Bianca Susara, who helped with the graphical abstract. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the US Government or any agency thereof. Neither the US Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed or represents that its use would not infringe privately owned rights.
Keywords
- Pseudomonas putida
- cholinium lysinate
- depolymerization
- ionic liquid (IL)
- life cycle assessmen
- polyethylene terephthalate (PET)
- polyhydroxyalkanoates (PHA)
- polylactic acid (PLA)
- techno-economic analysis
- waste recycling