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Oxidation of U(IV) in HNO3 Solutions Containing Urea and Tc(VII)

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Abstract

The kinetics of U(IV) oxidation with nitric acid in aqueous solutions containing urea, catalyzed with technetium ions, were studied by sampling with subsequent colorimetric determination of the U(IV) concentration. At the constant ionic strength of the solution μ = 2 in the range of the initial concentrations of U(IV) from 2 × 10−3 to 1.28 × 10−2, Tc(VII) from 5 × 10−5 to 1 × 10−3, urea from 0.01 to 0.1, and hydrogen ions from 0.4 to 1.96 M, the reaction rate is described by the equation -d[U(IV)]/dt = k 1[U(IV)][Tc]0.5[CO(NH2)2] × {[H+]2 + β1[H+] + β2}−1 - k 2[U(IV)]2[H+]0.4[CO(NH2)2]1.6{ [H+]2 + β1[H+]+ β2}−2, where k 1 = 172 ± 10 mol0.5 l−0.5 min−1 and k 2 = (9.4±1.2)×102 mol l−1 min−1 at 25°C, β1 and β2 are the hydrolysis constants of U4+ ions. The activation energy is 63±2 kJ mol−1. A reaction mechanism is proposed, in which in the slow stages the complex ion U(OH) 2+2 ·CO(NH2)2 reacts with TcO2+ and TcO2+ · CO(NH2)2 ions.

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REFERENCES

  1. Koltunov, V.S., Kinetika reaktsii aktinoidov (Kinetics of Actinide Reactions), Moscow: Atomizdat, 1974, p. 58.

    Google Scholar 

  2. Koltunov, V.S. and Marchenko, V.I., Kinet. Katal., 1966, vol. 7, no.2, p. 224.

    Google Scholar 

  3. Koltunov, V.S. and Gomonova, T.V., Radiokhimiya, 1991, vol. 33, no.5, p. 107.

    CAS  Google Scholar 

  4. Taylor, R.J., Koltunov, V.S., Marchenko, V.I., et al., J. Nucl. Sci. Technol., 2002, suppl. 3, p. 355.

    Google Scholar 

  5. Dvoeglazov, K.N. and Marchenko, V.I., Radiokhimiya, 2005, vol. 47, no.4, pp. 57–60.

    Google Scholar 

  6. Koltunov, V.S. and Gomonova, T.V., Radiokhimiya, 1988, vol. 30, no.6, pp. 756–760.

    CAS  Google Scholar 

  7. Koltunov, V.S. and Gomonova, T.V., Radiokhimiya, 1985, vol. 27, no.4, pp. 394–399.

    CAS  Google Scholar 

  8. Koltunov, V.S. and Gomonova, T.V., Radiokhimiya, 1984, vol. 26, no.3, pp. 328–332.

    CAS  Google Scholar 

  9. Koltunov, V.S., Khimiya transuranovykh i oskolochnykh elementov (Chemistry of Transuranium and Fission Elements), Moscow: Nauka, 1967, pp. 8–14.

    Google Scholar 

  10. Koltunov, V.S. and Gomonova, T.V., Radiokhimiya, 1990, vol. 32, no.5, pp. 70–72.

    Google Scholar 

  11. Nazarenko, V.A., Antonovich, V.P., and Nevskaya, E.M., Gidroliz ionov metallov v razbavlennykh rastvorakh (Hydrolysis of Metal Ions in Dilute Solutions), Moscow: Atomizdat, 1979.

    Google Scholar 

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Authors and Affiliations

  1. Bochvar Russian Research Institute of Inorganic Materials, State Scientific Center of the Russian Federation, Moscow, Russia

    K. N. Dvoeglazov, V. I. Marchenko & V. S. Koltunov

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  1. K. N. Dvoeglazov
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  2. V. I. Marchenko
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  3. V. S. Koltunov
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Translated from Radiokhimiya, Vol. 47, No. 1, 2005, pp. 61–66.

Original Russian Text Copyright © 2005 by Dvoeglazov, Marchenko, Koltunov.

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Dvoeglazov, K.N., Marchenko, V.I. & Koltunov, V.S. Oxidation of U(IV) in HNO3 Solutions Containing Urea and Tc(VII). Radiochemistry 47, 63–68 (2005). https://doi.org/10.1007/s11137-005-0049-y

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