Gas dehydration using the ionic liquid [EMIM][MeSO3] supported on silica gel – Structural and water vapor sorption properties

Abstract

Structural and water vapor sorption properties of supported ionic liquid phase (SILP) materials, here of the ionic liquid [EMIM][MeSO3] coated on silica gels, were studied. The distribution of the IL over the silica supports is uniform. The porosity of the SILPs shows good agreement with expected values based on the density of the pure IL. The water sorption in pure [EMIM][MeSO3] as well as by the SILPs can be described by Guggenheim-Anderson-de Boer sorption isotherms. If the silica surface is covered by at least a complete monolayer of IL, the surface has no noticeable effect on the sorption capacity, and the capacity of the SILP corresponds to that of the pure IL until capillary condensation occurs. SILPs are promising candidates for gas dehydration, as the water sorption capacity per mass of silica is about six times higher compared to uncoated silica.