The extraction of uranium(VI) from aqueous solutions with dibutylditiophosphoric acid in organic solvents was studied. The influence of different factors as pH of the aqueous phase, extractant concentration and nature of solvent was investigated in order to find the optimum conditions for separation of metal from aqueous nitrate solutions. The effect of neutral donor extractants was also searched and the efficiency of the extraction was calculated.
Paper electrophoresis has been used for uranium(VI) separation from Fe(II), Co(II), Ni(II) and Cu(II). The background electrolyte (0.1M HNO3-NaNO3) at different pH values contains diethyldithiophosphoric acid as complexing agent. A plot of mobility versus pH is used to obtain information on the formation of dithiophosphate complexes and to compute the stability constant of an uranyldiethyldithiophosphate complex.
An improved method for the synthesis of four heterotrinuclearpolyacids of the type: Hx[EM′yM″zO40⋅nH2O (E=P, Si; M′=Mo, W; M″=V, W) was elaborated. The studied compounds were characterized by elemental analysis, IR spectra and thermal behaviour over
20–800C temperature range.
Authors:A. Fodor, L. Ghizdavu, A. Suteu, and A. Caraban
An improved method for the synthesis of two heteropolyacids of the same type: H5[AsMo10V2O40]·13H2O and H5[AsW10V2O40]·16H2O was elaborated. The studied compounds were characterized by elemental analysis, IR spectra and thermal behaviour over 20-800°C temperature range.
Authors:L. Ghizdavu, C. Bălan, L. David, C. Bâtiu, O. Cozar, and D. Ristoiu
New complexes CuL22H2O, CoL23H2O, MnL22H2O and FeL32H2O, L=γ-L -glutamyl-5-(p-nitroanilide), were synthesized and characterized by their spectral, magnetic and thermal properties. The thermal stabilities
of the synthesized complexes were examined in the temperature range 20–500C. In all these complexes γ-L -glutamyl-5-(p -nitroanilide) acts as a bidentate ligand, its coordination involving the carbonyl oxygen and the nitrogen atom of the second
amino group. The local structure around the Cu(II) ion is pseudotetrahedral. In the Co(II), Mn(II) and Fe(III) complexes,
the metal ions are in the high-spin form, with octahedral stereochemistry.