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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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Ranking Eco-Innovations to Enable a Sustainable Circular Economy with Net-Zero Emissions
The urgency of action toward mitigating climate change and reducing material leakage into the environment is inspiring a plethora of innovative technologies, supply chains, and policy actions. These are targeted toward reducing greenhouse gas emissions, natural resource uptake, and decoupling technological systems from fossil-based linear economies using circularity strategies. Industrial and governmental stakeholders are keen to rank these proposed eco-innovations and emerging alternatives based on their scope of contributing to a sustainable and circular economy to meet global warming curtailment and pollution mitigation targets. We describe a novel methodological framework that relies on a multiobjective optimization of cradle-to-cradle life-cycle pathways to screen from a large database of conceptual eco-innovations and rank them based on their potential for establishing a Sustainable Circular Economy (SCE). This methodology is implemented for a motivating case study to evaluate numerous packaging eco-innovations based on their improvement potential and readiness for adoption within the grocery bags value-chain network. It is demonstrated that a preliminary screening step identifies the 10 most promising eco-innovations from a large superset of alternatives, which if developed and adopted can help transition the value chain to a future scenario with net-zero emissions and adherence to the recycled and renewable-content targets set by the United States Plastics pact but at a higher cost.
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- Award ID(s):
- 2029397
- PAR ID:
- 10466760
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Sustainable Chemistry & Engineering
- Volume:
- 11
- Issue:
- 4
- ISSN:
- 2168-0485
- Page Range / eLocation ID:
- 1363 to 1374
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acssuschemeng.2c05732
