Mechanistic Understanding on Difluoromethane Absorption Thermodynamics on Novel Deep Eutectic Solvents by COSMO-Based Molecular Simulation

Hydrofluorocarbons (HFC) are fluorinated compounds used globally for refrigeration. These gases have been shown to contain a greenhouse potential of up 22,000 times that CO2. Thus, 1298 type-5 deep eutectic solvents (DES) were examined the absorption and interaction mechanisms difluoromethane (R32), due their non-polar attributes. Of these solvents, quaternary ammonium salts mixed with various species hydrogen bond donators (HBD) produced most favorable interactions, ln activity coefficients predicted be as low −1.39 at 1:1 compositional ratio. DES further studied analysis where pure tetrabutylammonium bromide showed strongest potential. The pressure study linear solubility increase reaching 86 mol/mol% in methyltrioctylammonium polyethylene glycol mixture 9 bar. van der Waals is driving force ~3x enthalpic release over bonding. All chemicals strong an environmentally friendly solution, evident through environmental health safety analysis.