Kinetics and mechanism of adsorption of one commercial basic dye (BB69) and one direct dye (DR227) from aqueous solutions using day were studied in the temperature range 15-75 degrees C. The clay was activated by treatment with sulfuric add. Two simplified kinetic models, pseudo first- and second-order equations, were tested. It was shown that the adsorption of both dyes could be well described by the pseudo second-order equation. Rate constants of the best-fit model were calculated, and the related apparent activation energies were also evaluated and discussed.