Solvent extraction of uranium (VI) by tributyl phosphate/dodecane from nitric acid medium

Abstract

Uranium (VI) extraction from nitric acid medium by 20% Tri Butyl Phosphate (TBP)/dodecane was carried out. The effects of the nature of the diluent and nitric acid concentration on uranium distribution ratio (Du) were investigated in this study. The experimental results showed that Du using different diluents increases in the order: chloroform, carbon tetrachloride, dodecane and n-hexane. The yellow cake [Di-Ammonium Uranyl U₂O_7(NH₄)₂] produced at the Uranium Recovery Pilot-Plant from the Syrian row phosphoric acid was used to carry out uranium extraction tests, using 20% TBP/dodecane. Results showed that impurities presented in the yellow cake role as a salting out agent, which explains the increasing of loading capacity of the organic phase. Infrared studies of UO_2(NO₃)₂/ 20%TBP in dodecane system are reported, uranium was extracted from aqueous solutions of 3 mol/dm³ HNO₃ containing different Analytical Grade uranyl nitrate concentrations. Infrared spectra of UO₂(NO₃)₂. 2TBP system indicated that chelation of nitrate to uranyl ion is bidentate. Quantitative analysis of TBP-uranyl nitrate complex in dodecane in the regions of P=O and U=O stretching vibrations is discussed.