Journal of Radioanalytical and Nuclear Chemistry

, Volume 298, Issue 3, pp 1777–1783 | Cite as

Speciation of the uranyl nitrate system via spectrophotometric titrations

Article

Abstract

The speciation of the uranyl nitrate system has been studied previously with limited success producing a wide range of stability constant values. The current literature has values for the mononitrate species, with scattered data for higher nitrate species. Furthermore, the reported values vary with experimental method. The work presented here examines the stability of the uranyl/nitrate/perchlorate/water system via spectrophotometric titrations with a focus on the predominance of the uranyl dinitrate species at low nitrate concentrations. Stability constants were determined at ionic strengths ranging from 1 to 6 molal followed by refinement with the specific ion interaction theory. The zero ionic strength stability constant of the uranyl dinitrate species was refined as log β (2,1)º = 3.37 ± 0.02 when including the stability constant for the uranyl mononitrate from Ahrland and 2.66 ± 0.02 without. These values are considerably higher than previous studies, which is attributed to the alternate speciation model used. The values generated in this work produce speciation diagrams that are consistent with published solvent extraction data of the uranyl nitrate system.

Keywords

Uranyl nitrate Spectroscopy SIT Stability constant 

References

  1. 1.
    Betts RH, Michels RK (1949) Ionic association in aqueous solutions of uranyl sulfate and uranyl nitrate. J Chem Soc Issue 0:S286–S294Google Scholar
  2. 2.
    Ahrland S (1951) The complex chemistry of the uranyl ion. VI. The complexity of uranyl chloride, bromide, and nitrate. Acta Chem Scand 5:1271–1282CrossRefGoogle Scholar
  3. 3.
    Klygin AE, Kolyada NS, Smirnova ID (1970) Spectrophotometric investigation of complex formation in the system uranyl nitrate–nitric acid–water. Zh Neorg Khim+ 15:3300–3303Google Scholar
  4. 4.
    Rao L, Tian G (2008) Thermodynamic study of the complexation of uranium(VI) with nitrate at variable temperatures. J Chem Thermodyn 40(6):1001–1006. doi: 10.1016/j.jct.2008.02.013 CrossRefGoogle Scholar
  5. 5.
    Suleimenov OM, Seward TM, Hovey JK (2007) A spectrophotometric study on uranyl nitrate complexation to 150 °C. J Solut Chem 36(9):1093–1102. doi: 10.1007/s10953-007-9175-9 CrossRefGoogle Scholar
  6. 6.
    Moulin C, Decambox P, Mauchien P, Pouyat D, Couston L (1996) Direct uranium(VI) and nitrate determinations in nuclear reprocessing by time-resolved laser-induced fluorescence. Anal Chem 68(18):3204–3209CrossRefGoogle Scholar
  7. 7.
    Day RA, Powers RM (1954) Extraction of uranyl ion from some aqueous salt solutions with 2-thenoyltrifluoroacetone. J Am Chem Soc 76(15):3895–3897. doi: 10.1021/ja01644a007 CrossRefGoogle Scholar
  8. 8.
    Wanner H, Forest I (eds) (1992) Chemical thermodynamics of uranium. Chemical thermodynamics, vol 1. Elsevier Science Publishers, New YorkGoogle Scholar
  9. 9.
    Banerjea D, Tripathi KK (1961) Association of uranium(VI) with anions in aqueous perchloric acid medium. J Inorg Nucl Chem 18:199–206CrossRefGoogle Scholar
  10. 10.
    Lahr VH, Knoch W (1970) Bestimmung von Stabilitätskonstanten einiger Aktinidenkomplexe. II. Nitrat- und Chloridkomplexe von Uran, Neptunium, Plutonium und Americium. Radiochim Acta 13:1–5Google Scholar
  11. 11.
    Nash K, Madic C, Mathur J, Lacquement J (2006) Actinide separation science and technology. In: Morss L, Edelstein N, Fuger J (eds) The chemistry of the actinide and transactinide elements. Springer, Netherlands, pp 2622–2798. doi: 10.1007/1-4020-3598-5_24 CrossRefGoogle Scholar
  12. 12.
    Grindler JE (1962) The radiochemistry of uranium. Nuclear science series. Subcommittee on Radiochemistry, National Academy of Sciences-National Research Council, Washington D.C.Google Scholar
  13. 13.
    Vandegrift GF, Regalbuto MC, Aase S, Bakel A, Battisti TJ, Bowers DL, Byrnes JP, Clark MA, Emery JW, Falkenberg JR, Gelis AV, Pereira C, Hafenrichter L, Tsai Y, Quigley KJ, Vander Pol MH (2004) Designing and demonstration of the UREX + process using spent nuclear fuel. Paper presented at the ATATLANTE 2004, Advances for Future Nuclear Fuel Cycles, Nimes, France, 21–24 June 2004Google Scholar
  14. 14.
    Marcus Y, Kertes AS (1969) Ion exchange and solvent extraction of metal complexes. Wiley-Interscience, New YorkGoogle Scholar
  15. 15.
    Buzko VY, Sukhno IV, Pettit LD (2007) The adjustment, estimation and uses of equilibrium reaction constants in aqueous solution. Tools of the trade, vol 29. IUPAC Analytical Chemistry DivisionGoogle Scholar
  16. 16.
    Ciavatta L (1980) The specific interaction theory in the evaluating ionic equilibria. Anal Chim 70:551–567Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2013

Authors and Affiliations

  1. 1.University of Nevada, Las VegasLas VegasUSA
  2. 2.Argonne National LaboratoryArgonneUSA

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