CO2 capture with hydrophobic halogen‐free natural deep eutectic solvents: Perturbed‐Chain Statistical Associating Fluid Theory modeling and molecular insights

Abstract This work systematically investigates CO 2 capture with hydrophobic halogen‐free natural deep eutectic solvents (NADES) as absorbents from both thermodynamic and molecular perspectives. A series of NADES consisting of decanoic acid, menthol, thymol, and lidocaine as hydrogen bond acceptors/donors (HBAs/HBDs) were prepared, and the CO 2 solubility in them was determined experimentally. Perturbed‐Chain Statistical Associating Fluid Theory has been first extended to simultaneously predict the thermodynamic properties (i.e., Henry's constants, enthalpy change, Gibbs free energy change and entropy change for CO 2 absorption in NADESs) as well as viscosity by combining with entropy scaling theory. Molecular insights into the structure–property relationship between different HBA/HBD structures and CO 2 solubility were revealed by quantum chemical calculations and molecular dynamics simulations. This work provides theoretical guidance for the development and screening of novel NADES for efficient CO capture.