Formation Of UO2 Research Articles

Extraction du nitrate d'uranyle par les sulfoxydes aliphatiques

After having recalled the main physical properties of the aliphatic sulfoxides, we demonstrated di- n-heptyl and di- n-octylsulfoxides could extract uranyl nitrate with a good yield, by formation of UO 2(NO 3) 2 · 2 sulfoxides type complex. With light sulfoxides, this complex has a low solubility in the diluant we used (carbon tetrachloride) and precipitates. Nitric acid in aqueous phase promotes extraction. This salting out effect reaches a maximum for a 4·5 N concentration. At last, we demonstrated that, for important concentrations, uranyl nitrate distribution coefficient was proportional to initial sulfoxide concentration.

The infra-red spectra of uranium species in carbon tetrachloride solutions of uranium (VI), dibutyl phosphoric acid and Tri- n-octyl phosphine oxide

Comparisons of the infra-red spectra of uranyl dibutyl phosphate polymer [UO 2(DBP) 2] n, tri- n-octyl phosphine oxide (TOPO), and dibutyl phosphoric acid (HDBP), for both the separate reagents and in combination in carbon tetrachloride, are consistent with the formation of UO 2(DBP) 2· 2TOPO, UO 2(DBP) 2HDBP·TOPO and UO 2(DBP) 2·2HDBP. The data imply that extraction of UO 2 +2 from aqueous solutions by combinations of tri- n-octyl phosphine oxide and dibutyl phosphoric acid dimer may be represented by the equations UO 2 2+ + 2( HDBP) 2 + TOPO ⇌ UO 2( DBP) 2· HDBP· TOPO + 1 2 ( HDBP) 2 + 2 H + UO 2 2 + ( HDBP) 2 + 2 TOPO ⇌ UO 2( DBP) 22 TOPO + 2 H + . Considerable hydrogen bonding between TOPO and HDBP occurs when these reagents are together in solution. The evidence for previously-postulated structural formulae for the uranium species is not conclusive, but the data are consistent with the equivalence of three DBP ligands in uranium species containing HDBP.