Application of excess adsorption data measured for components of the mobile phase for characterizing chromatographic systems

Abstract

An analytical equation for the capacity ratio of a chromatographed substance in a multicomponent mobile phase, involving energetic heterogeneity of the adsorbent surface and differences in the molecular areas of solute and solvents, has been discussed. This equation has been examined by using adsorption and chromatographic experimental data. Adsorption measurements have been made for liquid mixture of benzene + cyclohexane on silica gel and aluminium oxide at 293 K. The same liquid mixture and adsorbents were used in the chromatographic measurements. Numerical results obtained for the systems investigated show that the excess adsorption isotherms of mixed solvents are very useful in the interpretation of chromatographic data.