Hydrophobic Natural Deep Eutectic Solvents for Sustainable CO 2 Capture: Molecular Insights From Multiscale Modeling

This research delves into the physicochemical properties and CO 2 capture ability of a hydrophobic natural deep eutectic solvent (HNADES) consisting of piperitone (PIP) and linoleic acid in a 1:1 molar ratio. Through a multiscale computational approach involving COSMO‐RS calculations, quantum chemistry methods, and molecular dynamics simulations, we demonstrate that the considered system, via the development of strong hydrogen bonding interactions, both homo‐ and hetero‐associations, and in parallel with nonpolar domains through van der Waals interactions, creates a suitable situation for CO 2 capture. The nonpolar domains provide space available for accommodating CO 2 molecules without interfering with the fluid's hydrogen bonding Gnetwork. Molecular dynamics simulations show that CO 2 molecules are adsorbed following a two‐step mechanism: first, adsorption at the gas–liquid interface, and second, subsequent migration into the bulk liquid. Upon exposure to a simulated flue gas, the HNADES is significantly selective toward CO 2 , which permeates the fluid, with N 2 and O 2 molecules remaining predominantly, in the gas phase. The desorption of the adsorbed CO 2 is possible after a heating process, thus enabling sorption–desorption cycles for practical use. This sorbent has advantages of being eco‐friendly, having zero vapor pressure, and low water solubility, which makes it an optimal candidate for being involved in sustainable carbon capture technologies.