Capture of fluorinated severe greenhouse gases using deep eutectic solvents: PC ‐ SAFT modeling and molecular insights

Abstract This study uses thermodynamics and molecular mechanisms to systematically investigate the selective absorption of fluorinated gases (F‐gases), which are very severe greenhouse gases. Deep eutectic solvents (DESs) were used as absorbents, and three DES candidates were selected from a screening of 132 potential DESs. The screening involved viscosities and thermal stabilities of the DESs as well as Henry's constants of the F‐gases and their separation selectivity over other gases by conductor‐like screening model for real solvent calculations. Perturbed‐chain statistical associating fluid theory (PC‐SAFT) was employed to predict both the thermodynamics (i.e., Henry's constants, enthalpy change, Gibbs free energy change, and entropy change for F‐gas absorption in DESs) and the viscosity by combining PC‐SAFT with entropy scaling theory. The solubilities of F‐gases in the selected DESs were experimentally measured, which validated the PC‐SAFT predictions. The molecular‐level mechanisms behind selective absorption of F‐gases in DESs were explored by quantum chemical calculations and molecular dynamics simulations.