Chapter 6
Gas Chromatography Columns Using
Ionic Liquids as Stationary Phase
Mohsen Talebi, Rahul A. Patil and Daniel W. Armstrong
Abstract Ionic liquids satisfy the requirements of a gas chromatography stationary phase, among which characteristics include high viscosity, tunable selectivity
through structural modifications, good wettability with respect to fused silica capillaries, and high thermal stability. When incorporated in either the first or second
dimension of multidimensional gas chromatography, they offer unique selectivity
compared to conventional gas chromatography stationary phases. The utilization of
commercial ionic liquid columns for analysis of various analytes (i.e., fatty acids,
flavors and fragrances, organic pollutants, and petrochemical samples) in complex
matrices is described in this chapter. Thanks to their dual-nature behavior, IL-based
stationary phases provide unique separation for both polar and nonpolar molecules
in complex samples, such as essential oils. Moderately polar phosphonium-based
ionic liquid columns (i.e., SLB-IL59, SLB-IL60, and SLB-IL61) with high operating temperature are suitable for analysis of complex petrochemical and environmental samples. The high polarity of ionic liquid columns allows analysis of positional
isomers including those of unsaturated fatty acids. The other exceptional feature of
ionic liquid columns is their stability in the presence of water and oxygen at high
temperatures. Water-compatible ionic liquid-based gas chromatography capillary
columns facilitate the direct injection of aqueous samples without the requirement
of time-consuming sample pretreatment techniques.
Keywords Dicationic ionic liquids · Gas chromatography · Ionic liquid capillary
columns · Polarity · Thermal stability
6.1 Introduction
Simple inorganic salts have very high melting points, and this limits their applications
as solvents for chemical applications. Salts with bulky organic cations and inorganic
or organic anions generally melt at lower temperatures, and those with melting points
M. Talebi · R. A. Patil · D. W. Armstrong (B)
Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington,
TX, USA
e-mail: sec4dwa@uta.edu
© Springer Nature Switzerland AG 2020
M. B. Shiflett (ed.), Commercial Applications of Ionic Liquids, Green Chemistry
and Sustainable Technology, https://doi.org/10.1007/978-3-030-35245-5_6
131
Gas Chromatography Columns Using
Ionic Liquids as Stationary Phase
Mohsen Talebi, Rahul A. Patil and Daniel W. Armstrong
Abstract Ionic liquids satisfy the requirements of a gas chromatography stationary phase, among which characteristics include high viscosity, tunable selectivity
through structural modifications, good wettability with respect to fused silica capillaries, and high thermal stability. When incorporated in either the first or second
dimension of multidimensional gas chromatography, they offer unique selectivity
compared to conventional gas chromatography stationary phases. The utilization of
commercial ionic liquid columns for analysis of various analytes (i.e., fatty acids,
flavors and fragrances, organic pollutants, and petrochemical samples) in complex
matrices is described in this chapter. Thanks to their dual-nature behavior, IL-based
stationary phases provide unique separation for both polar and nonpolar molecules
in complex samples, such as essential oils. Moderately polar phosphonium-based
ionic liquid columns (i.e., SLB-IL59, SLB-IL60, and SLB-IL61) with high operating temperature are suitable for analysis of complex petrochemical and environmental samples. The high polarity of ionic liquid columns allows analysis of positional
isomers including those of unsaturated fatty acids. The other exceptional feature of
ionic liquid columns is their stability in the presence of water and oxygen at high
temperatures. Water-compatible ionic liquid-based gas chromatography capillary
columns facilitate the direct injection of aqueous samples without the requirement
of time-consuming sample pretreatment techniques.
Keywords Dicationic ionic liquids · Gas chromatography · Ionic liquid capillary
columns · Polarity · Thermal stability
6.1 Introduction
Simple inorganic salts have very high melting points, and this limits their applications
as solvents for chemical applications. Salts with bulky organic cations and inorganic
or organic anions generally melt at lower temperatures, and those with melting points
M. Talebi · R. A. Patil · D. W. Armstrong (B)
Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington,
TX, USA
e-mail: sec4dwa@uta.edu
© Springer Nature Switzerland AG 2020
M. B. Shiflett (ed.), Commercial Applications of Ionic Liquids, Green Chemistry
and Sustainable Technology, https://doi.org/10.1007/978-3-030-35245-5_6
131