Adsorption of uranium (VI) from aqueous solution on calcined and acid-activated kaolin

Kaolin was modified by calcination followed by acid-activation. This type of modification strongly increased the adsorption of uranium (VI) on kaolin. The equilibrium data agreed very well with the Langmuir model. Kinetic studies showed that the adsorption followed the pseudo-second-order model. Thermodynamic parameters showed the endothermic heat of adsorption and the feasibility of the process. (C) 2009 Elsevier B.V. All rights reserved.