Characterization of the solubilizing ability of tetraalkylammonium ionic liquids containing a pendant alkyl chain bearing a basic N,N-dimethylamino or N,N-dimethylaminoethoxy functionality

Abstract

Infinite dilution activity coefficients and gas-to-ionic liquid partition coefficients are reported for >40 different organic compounds dissolved in N-[2-(N′,N′-dimethylamino)ethyl]-N,N-(dimethyl)-1-propanaminium bis(trifluoromethylsufonyl)imide, N-[2-(N′,N′-dimethyl-amino)ethyl]-N,N-(dimethyl)-1-butanaminium bis(trifluoromethylsufonyl)imide, N-[2-(N′,N′-dimethylamino)ethoxyethyl]-N,N-(dimethyl)-1-propanaminium bis(trifluoromethylsufonyl)imide, and N-[2-(N′,N′-dimethylamino)ethoxyethyl]-N,N-(dimethyl)-1-butanaminium bis(trifluoromethylsufonyl)imide in the temperature range from 323.15K to 373.15K. Partial molar excess enthalpies and partial molar excess entropies of solution were calculated from the temperature dependence of the infinite dilution activity coefficient assuming a van't Hoff relationship. Abraham model ionic liquid-specific correlations were determined from the measured partition coefficients. The derived mathematical expressions described the observed partition coefficients to within a standard deviation of 0.14 log units (or less).