The interaction of Pb and Zn with Al2O3 in aqueous solution was studied as a function of pH and metal ion concentration. Results indicated the complexation of metal ions by oxide surfaces is strongly pH dependent; the extent of adsorption is a function of pH with an abrupt change within approximately 2 pH units. The adsorption of Pb and Zn on aluminium oxide can be interpreted in terms of a surface complexation formed by association with one surface AlOH group, thus releasing one bound hydrogen ion. -AlOH + M2+ = -AlOM+ + H+ . It is suggested that the major surface reaction is the formation of a monodentate inner-sphere complex.
Leung, Wing H. and Kimaro, A.
"Binding of Pb and Zn to Aluminium Oxide and Proton Stoichiometry,"
Virginia Journal of Science: Vol. 51
, Article 4.
Available at: http://digitalcommons.odu.edu/vjs/vol51/iss1/4