Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Equilibrium calculations for HyBRID decontamination of magnetite: Effect of raw amount of CuSO4 on Cu2O formation

  • Lee, Byung-Chul (Department of Chemical Engineering, Hannam University) ;
  • Kim, Seon-Byeong (Decommissioning Technology Research Division, Korea Atomic Energy Research Institute) ;
  • Moon, Jei-Kwon (Decommissioning Technology Research Division, Korea Atomic Energy Research Institute)
  • Received : 2019.12.18
  • Accepted : 2020.04.09
  • Published : 2020.11.25
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Abstract

Calculations of chemical equilibrium for multicomponent aqueous systems of the HyBRID dissolution of magnetite were performed by using the HSC Chemistry. They were done by using a Pitzer-based aqueous solution model with the recipe of raw materials in experiments conducted at KAERI. The change in the amounts of species and ions and the pH values of the solution at equilibrium was observed as functions of temperature and raw amount of CuSO4. Precipitation of Cu2O occurred at a large amount of CuSO4 added to the solution, while no precipitation of Cu(OH)2 was found at any amounts of CuSO4. The E-pH diagrams for Cu were constructed at various Cu concentrations to provide the effect of the Cu concentration on the pH values at boundaries where the coexistence of Cu+ ion and Cu2O solid occurred. To prevent Cu+ ions from being precipitated to Cu2O, the raw amount of CuSO4 should be adjusted so that the pH value of the solution from the equilibrium calculation is less than that from the E-pH diagram. We provided guidelines for the raw amount of CuSO4 and the pH value of the solution, which prevent the formation of Cu2O precipitates in the HyBRID dissolution experiments for magnetite.

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References

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