Ionic liquids-assisted fabrication of silica-based monolithic columns

The mesopores of a monolithic silica column are very important and useful for chromatographic separation since they can offer sufficiently large surface area. In this paper, a novel method with the assistance of an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate ([bmin]BF4)) was developed for the preparation of a C18-modified monolithic silica column for the first time, in which, the through pores and mesopores were formed simultaneously during the sol–gel reaction. The method is effective to simplify the preparation process of the silica-based monolithic columns. The factors influencing the sol–gel process, including the content of methanol and pH, were studied. The chromatographic performance of the prepared monolithic column was evaluated by the separation of alkylbenzenes.