title: Limiting partition coefficients of solutes in biphasic trihexyltetradecylphosphonium chloride ionic liquid-supercritical CO2 system: measurement and LSER-based correlation.
abstract: Limiting partition coefficients of a selection of low-to-medium volatility solutes between both phases in a biphasic trihexyltetradecylphosphonium chloride ([thtdp][Cl]) ionic liquid (IL)-supercritical carbon dioxide (scCO2) system were obtained by capillary column chromatography with [thtdp][Cl] as the stationary liquid and scCO2 as the carrier fluid. It is shown that supercritical fluid chromatography can be used to probe the partitioning behavior of solutes in biphasic IL-scCO2 systems even when the IL has nonzero solubility in scCO2. Relative partition coefficients of solutes at a particular temperature and density of CO2 can be correlated within Abraham's linear solvation energy relationships. Compared with our previous results in a [bmim][BF4]-scCO2 system, the solute partition coefficients in the [thtdp][Cl]-scCO2 system are more sensitive to the solute hydrogen bond acidity descriptor.
authors.affiliation: Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Veveí U+0159 97, 60200 Brno, Czech Republic.
authors.forename: Josef
authors.initials: J
authors.lastname: Planeta
authors.forename: Pavel
authors.initials: P
authors.lastname: Karásek
authors.forename: Michal
authors.initials: M
authors.lastname: Roth