Selective Adsorption of Europium on Activated Charcoal from Aqueous Solutions

Abstract

The adsorption of europium on activated charcoal has been studied as a function of shaking time, pH, concentration of adsorbate and temperature. The adsorption of europium obeys the Langmuir and Dubinin-Radushkevich isotherms. Thermodynamic quantities such as ΔH0 and ΔS0 have been calculated from the slopes and intercepts of plots of In KD versus 1/T. The influence of different cations and anions on europium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been investigated under specified conditions to check their selectivity for europium. As a result, europium has been successfully removed from a mixture containing Ba, Sr, Ru, Cs, Cr, Nd, Pr and In. Approximately 96% of the europium adsorbed on the activated charcoal was recovered using 45 ml of 3 M HNO3. X-ray fluorescence spectrometry was used for measuring the europium concentration.