CO2 capture using monoethanolamine (MEA) suffers from amine degradation, solvent emissions, and large heat requirements to regenerate the solvent. Ionic liquids are an attractive alternative to MEA that are thermally stable with virtually no vapor pressure and can be designed to reversibly bind CO2. We investigate the absorption of CO2 in the ionic liquid triethyloctylphosphonium 2-cyanopyrrolide, [P2228+][2CNpyr-] using reaction ensemble Monte Carlo (RxMC). We estimate the change in free energy of the reaction from quantum mechanical calculations and present CO2 absorption isotherms at a range of temperatures.
