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Monomers from CO₂ : Superbases as Catalysts for Formate-to-Oxalate Coupling.

ABSTRACT: An interesting contribution to solving the climate crisis involves the use of CO₂ as a feedstock for monomers to produce sustainable plastics. In the European Horizon 2020 project "OCEAN" a continuous multistep process from CO₂ to oxalic acid and derivatives is developed, starting with the electrochemical reduction of CO₂ to potassium formate. The subsequent formate-to-oxalate coupling is a reaction that has been studied and commercially used for over 150 years. With the introduction of superbases as catalysts under moisture-free conditions unprecedented improvements were shown for the formate coupling reaction. With isotopic labelling experiments the presence of carbonite as an intermediate was proven during the reaction, and with a unique operando set-up the kinetics were studied. Ultimately, the required reaction temperature could be dropped from 400 to below 200 °C, and the reaction time could be reduced from 10 to 1 min whilst achieving 99 % oxalate yield.

SUBMITTER: Schuler E

PROVIDER: S-EPMC8048464 | biostudies-literature |

REPOSITORIES: biostudies-literature

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