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Electrochemical conversion of biomass-derived intermediate compounds to high-value products has emerged as a promising approach in the field of biorefinery. Biomass upgrading allows for the production of chemicals from non-fossil-based carbon sources and capitalization on electricity as a green energy input. Amino acids, as products of biomass upgrading, have received relatively little attention. Pharmaceutical and food industries will benefit from an alternative strategy for the production of amino acids that does not rely on inefficient fermentation processes. The use of renewable biomass resources as starting materials makes this proposed strategy more desirable. Herein, we report an electrochemical approach for the selective oxidation of biomass-derived α-hydroxyl acids to α-keto acids, followed by electrochemical reductive amination to yield amino acids as the final products. Such a strategy takes advantage of both reactions at the anode and cathode and produces amino acids under ambient conditions with high energy efficiency. A flow electrolyzer was also successfully employed for the conversion of α-hydroxyl acids to amino acids, highlighting its great potential for large-scale application.
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Electrohydrodimerization of biomass-derived furfural generates a jet fuel precursor
Despite the increasing interest in upgrading biomass-derived molecules to value-added products, the electrochemical conversion of biomass platform chemicals to highly valuable biofuels, such as jet fuel, has not yet received wide attention. Herein, we report a catalyst-free electrochemical route for the production of a jet fuel precursor, hydrofuroin, from the electrohydrodimerization of furfural, which can be readily derived from lignocellulose and already has an industrial production of 300 000 tons per year. Detailed electrochemical studies using carbon and copper electrodes at various pH values enabled us to probe the reduction mechanism of furfural and obtain the kinetic details, such as the diffusion constant and electron transfer rate. Preparative electrolysis in a batch electrolyzer achieved a high yield of hydrofuroin (94%) with an excellent faradaic efficiency of 93%. Finally, a flow electrolyzer was employed to demonstrate the great promise of large-scale production of hydrofuroin from the electrohydrodimerization of furfural.
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- PAR ID:
- 10205265
- Date Published:
- Journal Name:
- Green Chemistry
- Volume:
- 22
- Issue:
- 16
- ISSN:
- 1463-9262
- Page Range / eLocation ID:
- 5395 to 5401
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0gc01720e
