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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Thermodynamic and Economic Assessments of Electrochemical CO 2 Conversion to Dimethyl Ether: Trade-off between Hydrogen Gas and Water Vapor as a Proton Source
Electrochemical conversion of carbon dioxide (CO2) to valuable products could provide a transformative pathway to produce renewable fuels while adding value to the CO2 captured at point sources. Here, we investigate the thermodynamic feasibility and economic viability of the electrochemical CO2 reduction reaction to various carbon-containing fuels. In particular, we explore various pathways for conversion of CO2 to dimethyl ether (DME), liquid propane gas, and renewable natural gas. We compare and contrast the use of two different proton sources, including hydrogen gas and water vapor at the anode, on the capital and operating costs (OPEX) of electrochemical systems to produce DME. The results indicate that the electrical costs are the most significant portion of OPEX, demonstrating costs of 0.2–0.6 $/kWh per metric ton of DME. DME production using carbon monoxide and formic acid as intermediates proved to be the most cost-effective, demonstrating levelized costs of energy of 0.28 $/kWh with over 0.15 $/kWh of cost recovery possible through renewable hydrogen tax credits and oxygen and hydrogen gas recovery.
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- Award ID(s):
- 1904351
- PAR ID:
- 10548522
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Industrial & Engineering Chemistry Research
- Volume:
- 63
- Issue:
- 33
- ISSN:
- 0888-5885
- Page Range / eLocation ID:
- 14582 to 14589
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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