AbstractThe adsorption processes ofp‐toluidine,p‐bromoaniline andp‐acetylaniline, from aqueous solution at 20°C, on heat‐treated sepiolite have been studied. With regard to the kinetic study, the processes have resulted in being second order in relation to the vacant active centres of the sepiolite, the highest value of the specific rate constant corresponding to thep‐acetylaniline and the lowest one to thep‐toluidine. The adsorption isotherms may be classified as L‐type (Giles classification) and the values of the adsorption capacity have been calculated from the Langmuir equation applied to the experimental data points. The highest values of the adsorption capacity and specific surface area also correspond to thep‐acetylaniline, and the lowest ones t