Adsorption of Cationic Surfactants on Silica Surface: 2. Comparison of Theory with Experiment

Possible application of the SCFA lattice model to describe the adsorption of ionic surfactants on the surface whose charge and potential can be changed under the effect of adsorbing surfactant was theoretically studied. Calculated isotherms of surfactant adsorption were compared with experimental adsorption isotherms of dodecylpyridinium chloride on silica. It was shown that, upon the adsorption of cationic surfactants on SiO2, the ionization of silanol surface groups is enhanced and the surface charge increases. The used set of parameters suggesting the interaction between the aliphatic tails of surfactant molecules and the surface made it possible to reach good agreement with the experiment.