Solubilities of isobutane and cyclopropane in ionic liquids

• Solubilities of isobutane and cyclopropane in two ionic liquids were reported.
• Solubilities were measured from T = (302 to 344) K and from (0.03 to 1.16) MPa.
• The effects of temperature and pressure on the solubilities were investigated.
• Solubilities of hydrocarbons in [HMIM][Tf2N] and [P(14)666][TMPP] were compared.
• A modified Krichevsky–Kasarnovsky equation was used to model experimental data.

In this work, we presented the solubilities of isobutane and cyclopropane in 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][Tf2N]) and trihexyl tetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ([P(14)666][TMPP]) from T = (302 to 344) K up to 1.16 MPa. Henry’s constants for isobutane and cyclopropane in [HMIM][Tf2N] and [P(14)666][TMPP] were calculated from experimental results. Solubilities of isobutane and cyclopropane in [HMIM][Tf2N] are apparently smaller than those in [P(14)666][TMPP]. The effects of temperature, pressure and the number of carbon atoms in the hydrocarbons on the solubility were investigated in detail. A modified Krichevsky–Kasarnovsky equation was successfully applied to correlate the experimental results. The mean absolute relative deviations and the maximum absolute relative deviations are less than (2.4 and 4.6)%, respectively.

Henry’s constants for isobutane and cyclopropane in [HMIM][Tf2N] and [P(14)666][TMPP].Figure optionsDownload as PowerPoint slide