Direct Air Capture and Integrated Conversion of Carbon Dioxide into Cyclic Carbonates with Basic Organic Salts

Direct air capture and integrated conversion is a veryattractivestrategy to reduce CO2 concentration in the atmosphere.However, the existing capturing processes are technologically challengingdue to the costs of the processes and the low concentration of CO2. The efficient valorization of the CO2 capturedcould help overcome many techno-economic limitations. Here, we presenta novel economical methodology for direct air capture and conversionthat is able to efficiently convert CO2 from the air intocyclic carbonates. The new approach employs commercially availablebasic ionic liquids, works without the need for sophisticated andexpensive co-catalysts or sorbents and under mild reaction conditions.The CO2 from atmospheric air was efficiently captured byIL solution (0.98 molCO(2)/mol(IL)) and, subsequently,completely converted into cyclic carbonates using epoxides or halohydrinspotentially derived from biomass as substrates. A mechanism of conversionwas evaluated, which helped to identify relevant reaction intermediatesbased on halohydrins, and consequently, a 100% selectivity was obtainedusing the new methodology. Captureof CO2 direct from the atmospheric airand transformation into added-value products under mild conditions.

Automated summary

This article presents an economically efficient method for direct air capture and conversion of CO2 into cyclic carbonates using commercially available basic ionic liquids, without the need for expensive catalysts or sorbents, and under mild reaction conditions.