Here,
we present a strategy for rapid measurement of gas solubility
in ionic liquids based on a simple configuration of tube-in-tube reactor.
Ionic liquids can be rapidly saturated without direct contact of gas
and liquid via a semipermeable Teflon AF-2400 inner tubing in the
reactor, and the gas solubility can be easily determined by a steady-state
flux balance of both gas and liquid flowing into the reactor. Solubility
data of gaseous carbon dioxide (CO2), ethylene (C2H4), and ethane (C2H6) in several
ionic liquids ([Emim][NTf2], [Omim][NTf2], [Bmim][BF4], [Bmim][PF6], and [Omim][NTf2]) were
successfully determined at temperatures between 30 °C and 60
°C and low pressure (no higher than 8 bar), showing less than
8% deviation, compared with the literature values. A single gas solubility
data point can be obtained within 10 min, showing high efficiency
compared with conventional methods (5–48 h). Finally, the application
scope and limitations of this method were discussed.