Effects Of Chemical Activation on Surface Sites of The Brick: pH-Dependence on Metal Adsorption

Oscar Allahdin, Belvia Bagoua, Michel Wartel, Joseph Mabingui, Abdel Boughriet

Brick was coated with ferrihydrite under variable experimental (pH) conditions. Pore – size distributions were determined and basic functions formed at brick surfaces were differentiated and quantified using pHmetry and conductimetry. Lead(II) and iron(II) adsorption capacities of synthesized compounds were tested by conducting fixed – bed column experiments. Both a higher pH used for Fe(III) precipitation into ferrihydrite and a higher level of deposited iron contributed to improve the adsorption performance of this material. The number of generated ΞAlO^-, ΞSiO^- and ΞFeO^- sites was found to be the key factor controlling the adsorption capacity level, and not physical and textural parameters.