Experimental Measurements and Molecular Dynamics Simulations of Self-Diffusivity in Mixtures of [CCim][TfN] with Difluoromethane and Pentafluoroethane.

Thermophysical properties of hydrofluorocarbon (HFC) gas and ionic liquid (IL) mixtures have previously been shown to exhibit large deviations from ideal solution behavior. Understanding self-diffusivity can help elucidate the contributing dynamic and structural properties. H and F NMR pulsed-field gradient stimulated echo techniques were utilized to measure the self-diffusion coefficients of the ions of 1-ethyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)amide ([CCim][TfN]) with either difluoromethane (HFC-32) or pentafluoroethane (HFC-125) at saturation with temperatures from 25 to 75 °C and pressures to 62 bar.