Adsorption of copper, cadmium and lead from aqueous solution to the kaolinite/water interface.

Abstract

The adsorption of Cu (II), Cd (II) and Pb (II) from aqueous solution to the kaolinite/water interface has been studied at 298.2 K as a function of both pH and ionic strength of the aqueous phase. The extent of adsorption increases with increasing pH and with decreasing ionic strength. Both effects can be explained by a model that assumes two kinds of binding sites: (a) weakly acidic groups XH that account for ion exchange, and (b) ampholytic surface hydroxyls SOH which form inner sphere complexes with the divalent metal ions. (Abstract retrieved from CAB Abstracts by CABI’s permission)