sorption, slag, metal cations, alkali-activated slag

New direction of research uses the alkali-activated slags as sorbents for removing metals cations from the solution. Modified slag materials prepared by alkaline activation were prepared and characterized with aim to study their sorption properties. Characterization of the prepared slags by means of infrared spectrometry demonstrates that the alkaline activation forms a new structure. The influence of this new structure on the sorption properties was studied for the copper and lead cations. The sorption experiments were performed by batch method in the aqueous solutions without pH treatment for the concentration range 2 ? 140 mmol/L. The maximum removal amounts of Cu(II) on the alkali-activated slags were almost three times higher and the maximum removal amounts of Pb(II) were at least twice higher in comparison to the original slag. A mechanism of the metal cations removing is influenced by self-alkalization and the removing is mainly due to precipitation and complexation of copper cations on the surface of slags. The alkaline activated slags can be possibly used for remediation of wastewater containing metals ions.