Rezumat
The effect of temperature on fluoride adsorption behavior of adsorption by thermo treated samples of aluminum alloy AMG-6 electrochemical machining products has been studied. Kinetic curves and adsorption isotherms at solution temperatures 20, 30, and 400С have been reseived and the adsorption velocity con- stants, diffusion coefficients and the values of activation energy have been determined. The Ea value ob- tained corresponds to values of activation energy characteristic for ion exchange processes controlled by in- ternal diffusion. Thermodynamic functions of the adsorption process − ΔF0, ΔH0, and ΔS0 have been calcu- lated. Differential free molar energy changes, isosteric heat and entropy of fluorine adsorption have been analyzed versus the filling degree of samples surface with fluorine-ions. The absence of process rate depen- dence on mixing velocities as well as the character of dependences of F (equilibrium degree reaching, %) on √ t demonstratethattheprocessunderconsiderationiscontrolledbyinternaldiffusionstep.Themechanism of fluorine ions fixation on the modified surface of aluminum oxyhydrates has been discussed.