Application of Activated Carbon for the Sorption of Some Heavy Metals from Aqueous Solution and Their Determination by Atomic Spectroscopy

Abstract

This paper presents investigations on the possible application of Polish active carbons, obtained by the carbonization of plum stones, in the sorption and preconcentration of selected heavy metal ions, i.e. Fe^III, Pb^II, Ni^II, Zn^II, Co^II and Cd^II, from aqueous solution. The effect of modifying the active carbon surface with oxidizing (HNO₃, H₂O, air and steam) and reducing (H₂) agents on the sorption and ion-exchange capacity of the carbon was examined. The basic characteristics of the porous structure of the tested adsorbents, as well as their ion-exchange capacities towards cations and anions, were determined. In addition, the sorption isotherms of individual ions in the concentration range 10⁻⁴–10⁻² mol/1, as well as the effect of the pH of the solution on the sorption of the ions, were investigated. As far as the utilization of the prepared sorbents to isolate and preconcentrate trace amounts of tested ions is concerned, the best results were obtained for active carbons thermally treated at 800°C in a hydrogen atmosphere.