Single-component and competitive adsorption data of 2-phenylethanol and 3-phenylpropanol on ODS-silica with methanol-water as the mobile phase, which had been previously reported, were reinterpreted. These data were fitted to several isotherm models derived from statistical thermodynamics which consider lateral adsorbate-adsorbate interactions on homogeneous surfaces : the Fowler, Ruthven, and Moreau et al. models. The single-component Kiselev model for specific lateral interactions was extended to account for the competitive adsorption of binary mixtures and for the finite or infinite dimension of the adsorbed associates. These last models were tested using the same set of experimental data. A comparison was made regarding the ability of these models to predict mixed equilibria using only the identified parameters of the single-component isotherms. In this regard, the best results were obtained with the Kiselev model, which considers the formation of both binary and ternary associates on the surface.