Sorption of Uranium on Zirconium Phosphate Inorganic Cation Exchanger

Uranium sorption on the zirconium phosphate inorganic cation exchanger is studied. Zirconium phosphate (ZP) efficiently sorbs uranium from nitric acid solutions over the pH range 3.0-5.0. The uranium distribution coefficients decrease in the presence of nitrates of alkali and alkaline-earth metals. The kinetics of static desorption of uranium with HNO3 and also of its dynamic sorption and desorption are studied. The mechanism of U sorption on ZP is analyzed. The exchange rate of the hydrogen ions in the sorbent phase for uranyl ion is controlled by the gel kinetics, and the rate-determining stage is the inner diffusion of uranium in the sorbent grain. The kinetic parameters of this exchange are determined. The sorption rate doubles with increasing temperature from 20 to 40°C and pH from 3.0 to 5.0. © MAIK Nauka/Interperiodica 2001.