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Choline chloride-based deep eutectic solvents (DESs) are a new class of green solvents that are liquid in the range of operating conditions for most of the process industries. Due to their environmentally friendly nature, cost-effectiveness, easy preparation, and recyclability, they are popular and possible alternatives for conventional solvents in the process industries. In the present work, molecular dynamics (MD) simulations were employed to understand the free energy of solvation of four different gas molecules (H 2 S, CO 2 , CH 4 , and N 2 ) in DESs (ethaline, reline, glyceline, and oxaline); thereafter, the Henry's law constant, solvation enthalpy, entropy, and selectivity were computed.The trends observed for solubility revealed that all of the studied DESs followed the order of H 2 S > CO 2 > CH 4 > N 2 , consistent with similar observations in other solvents. Similarly, the solvation enthalpy (ΔH sol ) for the investigated gases in the DESs followed a similar order of H 2 S > CO 2 > CH 4 > N 2 . Ideal gas selectivities (S CO /CH 2 4 and S H S/CH 2 4 ) for reline were found to agree reasonably well with the available literature data, and those for glyceline were found to be the highest with regards to the natural gas sweetening process. In addition, selectivities (S CO /N 2 2 and S H S/N 2 2 ) were also the highest for glyceline in the flue gas treatment application, having values of ∼200 and ∼1354, respectively, at the temperature 298.15 K. Finally, computation of selectivity from the MD simulation provides a screening tool for the selection of solvents for gas-separation processes.

Molecular dynamics simulations of fullerene and fullerols [C(OH), where n = 2-30] in aqueous solutions have been performed for the purpose of obtaining a detailed understanding of the structural and dynamic properties of these nanoparticles in water. The structures, dynamics and hydration free energies of the solute molecules in water have been analysed. Radial distribution functions, spatial density distribution functions and hydrogen bond analyses are employed to characterize the solvation shells of water around the central solute molecules. We have found that water molecules form two solvation shells around the central solute molecule. Hydrogen bonding in the bulk solvent is unaffected by increasing n. The large decrease in solvation enthalpies of these solute molecules for n > 14 enhances solubilisation. The diffusion constants of solute molecules decrease with increasing n. The solvation free energy of C in water is positive (52.8 kJ/mol), whereas its value for C(OH) is highly negative (-427.1 kJ/mol). The effects of surface hydroxylation become more dominant once the fullerols become soluble.