Effect of the temperature and oxalic acid in the uranyl sorption in zircon

In this work the results of the temperature effect study are presented on uranyl solutions adsorbed on zirconium silicate (ZrSiO4) and also on the compounds formed in surface with oxalic acid. The adsorption isotherms of uranyl on hydrated zircon with NaClO4 0.5 M, show an increase of the uranyl sorption efficiency when increasing the temperature from 20 to 4 C with a sudden descent in this efficiency when changing the temperature at 60 C. The uranyl sorption efficiency increases to hydrate the zircon with a solution of oxalic acid 0.1 M, maintaining the same tendency regarding to the temperatures of the sorption in medium NaClO4 0.5 M. The complex formation in the zircon surface with organic acids of low molecular weight increases the fixation of the uranyl in solution due to the formation of ternary systems, in the order Zircon/A. Organic/Uranyl, without altering their response to the temperature. (Author)