Kinetics study and thermodynamic behavior for removing cesium, cobalt and nickel ions from aqueous solution using nano-zirconium vanadate ion exchanger

The goal of this batch-test kinetic study is to evaluate the effectiveness of the different prepared nano-zirconium vanadate ion exchangers for removing cesium, cobalt and nickel from aqueous solution. The prepared samples are characterized using X-ray diffraction, Scanning Electron Microscope and Specific surface area. Analysis of the respective rate data in accordance with three kinetic models is applied. It is revealed that the kinetics of cesium sorption onto the different prepared inorganic nano-zirconium vanadate ion exchangers can be described well by the second-order and Elovich kinetic model. However, cobalt and nickel sorption kinetics may be described by the first, second-order and Elovich kinetic models. It is established that the ion exchange mechanism plays a significant role in all studied cesium sorption systems and may participate with a small extent in the studied cobalt and nickel sorption systems. Moreover, the sorption systems are governed mainly by intraparticle diffusion. Finally, nano-zirconium vanadate produced from homogeneous precipitation is selected for investigating the kinetic effect of the agitation speed and the solution temperature on the different three ion removals. It is recognized that the activation energy and the thermodynamic parameters for the sorption systems of studied ion removal using the homogeneous precipitated nano-zirconium vanadate ion exchanger are determined. (C) 2010 Elsevier B.V. All rights reserved.