Preparation and characterization of silica confined ionic liquids as chromatographic stationary phases through surface radical chain-transfer reaction

Ionic liquids (ILs) have been used in various regions of chemistry. Ionic liquids have designability, thus giving us the ability to manipulate the structure (with respect to the organic cation, inorganic anion and the length of the side chain attached to the organic cation) and consequently their properties. In this manuscript, two new different chromatographic stationary phases based on different ionic liquid-modified silica particles were prepared through surface radical chain-transfer reaction and characterized with elemental analysis, Raman spectroscopy and X-ray photoelectron spectroscopy. 1-Allyl-3-butylimidazolium ionic liquid-modified silica particles can be used as a strong anion-exchange stationary phase. 1-Allyl-3-(butyl-4-sulfonate)imidazolium ionic liquid-modified silica particles were used for the first time as the covalently bonded charge-balanced zwitterionic stationary phase in electrostatic ion chromatography for the simultaneous separation of inorganic anions and cations with pure water as the mobile phase.