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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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Renewable energy storage via efficient reversible hydrogenation of piperidine captured CO 2
The storage of renewable energy is the major hurdle during the transition of fossil resources to renewables. A possible solution is to convert renewable electricity to chemical energy carriers such as hydrogen for storage. Herein, a highly efficient formate-piperidine-adduct (FPA) based hydrogen storage system was developed. This system has shown rapid reaction kinetics of both hydrogenation of piperidine-captured CO 2 and dehydrogenation of the FPA over a carbon-supported palladium nano-catalyst under mild operating conditions. Moreover, the FPA solution based hydrogen storage system is advantageous owing to the generation of high-purity hydrogen, which is free of carbon monoxide and ammonia. In situ ATR-FTIR characterization was performed in order to provide insight into the reaction mechanisms involved. By integrating this breakthrough hydrogen storage system with renewable hydrogen and polymer electrolyte membrane fuel cells (PEMFC), in-demand cost-effective rechargeable hydrogen batteries could be realized for renewable energy storage.
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- Award ID(s):
- 1748579
- PAR ID:
- 10076369
- Date Published:
- Journal Name:
- Green Chemistry
- Volume:
- 20
- Issue:
- 18
- ISSN:
- 1463-9262
- Page Range / eLocation ID:
- 4292 to 4298
- 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/10.1039/C8GC00954F
