Ideal gas solubilities and solubility selectivities in a binary mixture of room-temperature ionic liquids

Journal Article · Tue Jul 01 00:00:00 EDT 2008 · Journal of Physical Chemistry B

DOI:https://doi.org/10.1021/jp075572l· OSTI ID:21212850

Alexia, Finotello; Bara, Jason E; Suguna, Narayan; Dean, Campder; Noble, Richard D ^[1]

---

1. University of Colorado, Boulder, CO (United States)

This study focuses on the solubility behaviors of CO{sub 2}, CH{sub 4}, and N{sub 2} gases in binary mixtures of imidazolium-based room-temperature ionic liquids (RTILs) using l-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide ((C{sub 2}mim)(Tf{sub 2}N)) and l-ethyl-3-methylimidazolium tetrafluoroborate ((C{sub 2}mim)(BF{sub 4})) at 40{sup o}C and low pressures (about 1 atm). The mixtures tested were 0, 25, 50, 75, 90, 95, and 100 mol % (C{sub 2}mim)(BF{sub 4}) in (C{sub 2}-mim)(Tf2{sub N}). Results show that regular solution theory (RST) can be used to describe the gas solubility and selectivity behaviors in RTIL mixtures using an average mixture solubility parameter or an average measured mixture molar volume. Interestingly, the solubility selectivity, defined as the ratio of gas mole fractions in the RTIL mixture, of CO{sub 2} with N{sub 2} or CH{sub 4} in pure (C{sub 2}mim)(BF4) can be enhanced by adding 5 mol% (C{sub 2}-mim)(Tf{sub 2}N).

• OSTI ID: 21212850
• Journal Information: Journal of Physical Chemistry B, Vol. 112, Issue 8; ISSN 1520-6106
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CARBON DIOXIDE
METHANE
NITROGEN
BINARY MIXTURES
IMIDAZOLES
SPECIFICITY
GASES
IONIC COMPOSITION
LIQUIDS
AMBIENT TEMPERATURE