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Kinetics of UO2 (s) Dissolution in the Presence of Hypochlorite, Chlorite, and Chlorate Solutions

Published online by Cambridge University Press:  01 February 2011

Rosa Sureda
Affiliation:
Dept. Chemical Engineering, Universitat Politécnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona, Spain
Ignasi Casas
Affiliation:
Dept. Chemical Engineering, Universitat Politécnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona, Spain
Javier Giménez
Affiliation:
Dept. Chemical Engineering, Universitat Politécnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona, Spain
Joan de Pablo
Affiliation:
Dept. Chemical Engineering, Universitat Politécnica de Catalunya, Avda. Diagonal 647, 08028 Barcelona, Spain Environmental Technology Area-CTM Centre Tecnológic, Avda. Bases de Manresa 1, 08242 Manresa, Spain
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Abstract

The influence of hypochlorite, chlorite and chlorate in the UO2 dissolution rate has been studied experimentally using a continuous flow-through reactor. Uranium concentration in each outflow solution was measured as a function of time and dissolution rates were determined once the steady-state was reached. The results obtained show that the influence of the hypochlorite anion concentration on the UO2 dissolution rate can be expressed by the following empirical equation

rdiss = 10-8.7±0.1•[ClO-]0.28±0.04

The dissolution rates obtained in this work were higher than those previously determined in presence of either oxygen or hydrogen peroxide using the same experimental methodology.

In contrast, neither chlorate nor chlorite had any significant effect on the UO2 dissolution rates under the experimental conditions of this work.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

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