Published online by Cambridge University Press: 01 January 2024
A detailed investigation of the adsorption of phenol and m-cresol from dilute aqueous solution by dodecyl- and tetradecylammonium bentonites has been carried out. The Freundlich isotherms for the tetradecylammonium bentonite system indicate that during adsorption, the process proceeds in two stages, the partial molar heat of adsorption changing from a positive to a negative value with a relatively small change in concentration of adsorbate. In the light of these findings, the aspects of the adsorption are discussed in terms of thermodynamic quantities, spatial considerations, and interlamellar expansion of the clay mineral.