Analysis of amylbenzene adsorption equilibria on different RP-HPLC.

For the purpose of description of the adsorption process of amylbenzene on a C8-, C18-, and C30-bonded silica stationary phase with methanol-water (80:20, v/v) as the mobile phase, a novel adsorption model (called the cluster isotherm model) is used. The model assumes the possibility of independent adsorption of analyte clusters on the longer C30 and shorter C8 chains. The validation of the proposed isotherm is made by comparison of experimental breakthrough and peak profiles obtained for RP-8e and RP-30 columns at a temperature of 24 degrees C and for RP-18e at a temperature range of 7-60 degrees C, with a theoretical simulation using the Transport-Dispersive model.