Molecular Screening of Amino Acid Ionic Liquids in CO2 Capture via COSMO-RS and DFT

Ionic liquids (ILs) are one of the main focuses of researchers to replace conventional solvents as they are known as 'green' solvents and possess many advantages.Recently, direct air capture (DAC) of carbon dioxide (CO2) systems has become the subject of extensive scientific study, as it causes severe effects on the environment and humans.Carbon capture is one of the techniques that could be used to reduce CO2 emissions.This study used a conductor-like screening model for real solvents (COSMO-RS) as an initial screening tool to design and identify the performance between anions and cations of amino acid ILs (AAILs) for CO2 capture.The chosen bestperformance AAILs are Tetrabutylammonium and Tetrabutylphosphonium paired with phenylalanine, serine, glycine, and aspartate.The results were compared with the density functional theory (DFT) calculation and molecular modelling.Moreover, the viscosity and ionic conductivity of the chosen AAILs were also studied.The significance of this study is to reduce time and expenses in selecting acceptable AAILs and comparing their CO2 capture performance via COSMO-RS and DFT.It should also boost the chances of finding new task-specific ILs (TSILs).