Comparative Characterization of Octyl Bonded Phases using Methylene Selectivity Data

Retention measurements of alkyl benzenes were carried out on the synthesized silica-based octyl bonded phases. The partition-displacement model was employed to analyze chromatographic properties of these phases. Namely, the methylene selectivity data were used to calculate the equilibrium sorption constant, the surface phase composition, and the sorption excess of water for each octyl phase. The differences in the surface phase composition of the phases studied were correlated with the structural and surface properties of the modified silica gels.