Reduction Kinetics of Uranium Trioxide to Uranium Dioxide Using Hydrogen
- 1 Sección de Geología y Minería, Departamento de Materiales Nucleares, Comisión Chilena de Energía Nuclear, Santiago, Chile
- 2 Sección de Geología y Minería, Departamento de Materiales Nucleares, Comisión Chilena de Energía Nuclear, Santiago, Chile
- 3 Ingeniería Civil Metalurgia, Universidad Andrés Bello, Santiago, Chile
Abstract
This article presents a study on the kinetics of the uranium conversion process, consisting in the reduction of uranium trioxide to uranium dioxide using hydrogen gas at temperatures of 500°C, 600°C and 700°C. Hydrogen concentrations used in the flow were 0.25 M, 0.50 M and 0.75 M. The mechanism established for the study of the kinetics of reduction of uranium trioxide was through the formation of an intermediate compound, U 3 O 8 . For this reason, these tests were divided into 2 stages: the first one the reduction from UO 3 to U 3 O 8 , and second one from U 3 O 8 to UO 2 . The results of each test were quantified by the release of H 2 O(g) produced by both reactions. Tests showed that the ideal working conditions are for hydrogen concentration flows of 0.75 M and temperatures in the range of 500°C - 600°C, with the intent to decrease the occurrence of side reactions that interfere with the process.
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