| Title |
A Thermodynamic Model on the Separation of Cobalt (2) and Nickel (2) from buffered Sulfate Solutions with D2EHPA |
| Authors |
이만승(M . S . Lee); 손성호(S . H . Son); 이응조(E . C . Lee) |
| Abstract |
A Thermodynamic model which considered chemical and phase equilibria as well as mass and charge balance equations and activity coefficients of all solutes simultaneously was developed for the separation of cobalt and nickel from buffered sulfate solutions with D₂EHPA dissolved in kerosene. By using the phase equilibrium constants of extracted species and interaction parameters obtained from the respective extraction experiments of individual metal ions, we could predict the distribution coefficients of cobalt and nickel and separation factors from initial extraction conditions of mixed solution. The separation factors increased with the concentration of D₂EHPA in the range of more than 0.05M due to the increase of the activity coefficients of extracted nickel species. In applying the model to the effect of extraction temperatures, the predicted values of distribution coefficients and separation factors were in good agreement with those obtained experimentally at 25℃ and 15℃. |