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Here, we show production pathways for greenhouse gas (GHG)-negative bio-based plastics from 2nd and 3rd generation feedstocks. We focus on bio-based plastics that are technically capable of replacing 80% of the global plastic market. By presenting life cycle inventories and discussing GHG-emissions hotspots, this work will inform stakeholders along the plastic supply chain of the necessary steps to achieving net-zero emissions by 2050, and potentially, how to drive net-uptake. This work is of critical importance given the overwhelming mass of plastic produced annually and the resulting CO2 emissions. To conduct this assessment, we derive life cycle inventories for nine different bio-based plastics and address the impact of methodological choices, such as allocation method, on the resulting 100a global warming potential (GWP). Our findings show that resources used and processing methods implemented have significant effects on the potential for us to derive carbon-negative plastics. Furthermore, we find that environmental impact quantification methods greatly influence the perceived GWP of such processes. For example, economic and mass allocation methods resulted in an apparent increase in GWP of up to 39% and 166%, respectively, compared to no allocation for bio-based plastics made from 2nd generation crops, whereas mass allocation resulted in the lowest GWP for bio-based plastics made from 1st generation crops. In considering environmental impact hotspots, our findings show that decarbonization of thermal energy and electricity, reduced use of ammonia-based fertilizer, renewable hydrogen production, use of bio-based alternatives for petrochemicals and plasticizers, enzyme production pathways from 2nd generation crops, and more efficient biomass conversion processes to reduce feedstock inputs may be critical steps in creating GHG negative bio-based plastics in the future.
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This content will become publicly available on March 28, 2026
Advances in non-thermal and electrochemical CO2 conversion technologies towards net-zero emissions
The escalating challenges posed by extreme climate change and the rapid greenhouse effect have heightened stress and urgency among governments, researchers, and the public. Greenhouse gas (GHG) emissions, particularly carbon dioxide (CO2), have signi昀椀cantly contributed to rising atmospheric temperatures, with agriculture, forestry, and industrial activities accounting for 22 % and 17 % of global emissions, respectively. In 2022, global GHG emissions reached 53.8 Gt CO2eq, underscoring the critical need for net-zero technologies and a circular carbon economy. This review systematically evaluates the ef昀椀ciencies of non-thermal and electrochemical CO2 conversion technologies, including plasma, arti昀椀cial photosynthesis, and electrochemical methods, for achieving net-zero emissions. These advanced technologies offer promising pathways for converting CO2 into value-added chemicals, such as syngas, methanol, and formic acid, while reducing atmospheric CO2 concentrations. However, upscaling these technologies from laboratory to industrial scales presents signi昀椀cant challenges, including high energy consumption, economic feasibility, and environmental impacts. The review highlights the mechanisms of CO2 conversion, economic considerations, and the potential for industrial implementation. Priority research directions are identi昀椀ed, focusing on ecological footprints, green supply chains, and the integration of renewable energy sources. By addressing these challenges, non-thermal and electrochemical CO2 conversion technologies can play a pivotal role in mitigating climate change and advancing toward a sustainable, circular carbon economy.
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- Award ID(s):
- 2132178
- PAR ID:
- 10639177
- Publisher / Repository:
- Elsevier Ltd.
- Date Published:
- Journal Name:
- Cleaner engineering and technology
- ISSN:
- 2666-7908
- Subject(s) / Keyword(s):
- Artificial photosynthesis CO2 conversion Electrochemical conversion Net-zero emissions Plasma technology reactor design.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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