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Recycling of Li2ZrO3 as LiCl and ZrO2 via a Chlorination Technique

  • Received : 2021.02.10
  • Accepted : 2021.03.12
  • Published : 2021.06.30

Abstract

In this study, a chlorination technique for recycling Li2ZrO3, a reaction product of ZrO2-assisted rinsing process, was investigated to minimize the generation of secondary radioactive pyroprocessing waste. It was found that the reaction temperature was a key parameter that determined the reaction rate and maximum conversion ratio. In the temperature range of 400-600℃, an increase in the reaction temperature resulted in a profound increase in the reaction rate. Hence, according to the experimental results, a reaction temperature of at least 450℃ was proposed to ensure a Li2ZrO3 conversion ratio that exceeded 80% within 8 h of the reaction time. The activation energy was found to be 102 ± 2 kJ·mol-1·K-1 between 450 and 500℃. The formation of LiCl and ZrO2 as reaction products was confirmed by X-ray diffraction analysis. The experimental results obtained at various total flow rates revealed that the overall reaction rate depends on the Cl2 mass transfer rate in the experimental condition. The results of this study prove that the chlorination technique provides a solution to minimize the amount of radioactive waste generated during the ZrO2-assisted rinsing process.

Keywords

Acknowledgement

This work was sponsored by the Nuclear R&D program of the Korean Ministry of Science and ICT (2017M2A8A5015147 and 2017M2A8A5015077).

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