Cycloaddition of CO2 with epoxides into cyclic carbonates catalyzed by a binary organocatalyst under mild conditions

Abstract

Fixing CO₂ into value-added cyclic carbonates is an effective way to reduce CO₂ emissions. A metal-free and solvent-free catalytic system has been developed for the cycloaddition of CO₂ with epoxides into corresponding cyclic carbonates. The catalytic system can in situ catalyze the conversion of CO₂ into cyclic carbonates from actual flue gas under atmospheric pressure with a carbonate yield of up to 99.4%. The water resistance experiment and catalytic mechanism were investigated in detail. A ten-fold amplification reaction was conducted at 70 °C and atmospheric pressure, and the residual CO₂ in the flue gas decreased to 985 ppm, indicating that the CO₂ in the flue gas was effectively captured and removed under very mild conditions. This work provides a feasible approach for in situ capture and conversion of CO₂ in flue gas at atmospheric pressure.