Adsorption characteristic of U(VI) ion onto thermally activated bentonite

In this study, the effect of pH, contact time, temperature, and initial metal concentration on U(VI) adsorption on thermally activated bentonite (TAB) was investigated. Graphical correlation of various adsorption isotherm models like, Freundlich, and Dubinin-Radushkevich have been carried out for TAB. Various thermodynamic parameters, such as, Gibb's free energy, entropy and enthalpy of the on-going adsorption process have been calculated. In order to reveal the adsorptive characteristic of bentonite samples, surface area, FT-IR, and DTA-TG spectra analyses were carried out. The results show that TAB samples can be an alternative low cost adsorbent for removing U(VI) ions from aqueous solutions. (C) 2009 Elsevier B.V. All rights reserved.