, Volume 47, Issue 1, pp 39–44 | Cite as

Complexation of Np(V) with Silicate Ions

  • A. B. Yusov
  • A. M. Fedoseev
  • O. V. Isakova
  • C. H. Delegard


It was shown that Np(V) forms complexes with anions of orthosilicic acid and other silicate ions at pH higher than 8–8.5. At pH < 9.5, the reaction is mainly described by the equation NpO 2 + + OSi(OH) 3 ⇄ NpO2OSi(OH)3; the stability constant of the NpO2OSi(OH)3 complex is equal to log β1 = 2.1 ± 0.3. Thus, interaction is weak and hardly significant under real conditions. Carbonate ions in equilibrium with air at pH > 8.5 are the substantially stronger ligands for NpO 2 + , and in their presence it is impossible to reveal Np(V) complexation with silicate ions.


Silicate Stability Constant Real Condition Orthosilicic Acid Strong Ligand 
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Copyright information

© MAIK “Nauka/Interperiodica” 2005

Authors and Affiliations

  • A. B. Yusov
    • 1
  • A. M. Fedoseev
    • 1
  • O. V. Isakova
    • 1
  • C. H. Delegard
    • 2
  1. 1.Institute of Physical ChemistryRussian Academy of SciencesMoscowRussia
  2. 2.Pacific Northwest National LaboratoryRichlandUSA

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