Abstract
The distribution ratios of Sb and Cu {LS/CuX=(mass% of X in slag)/[mass% of X in copper], X=Sb or Cu} between Na2CO3 slag and molten copper have been determined for various partial pressures of CO2 at 1523 K as a function of the oxygen partial pressure calculated from the oxygen content in molten copper by using appropriate thermodynamic data. The distribution ratios of Sb and Cu are both affected strongly by the partial pressure of CO2. This effect for Sb can be evaluated by the equation [formula-omitted] (Q: a constant determinable experimentally) using activity data of NaO0.5 in Na2O-CO2-Sb2O5 melt under various partial pressures of CO2 which have been measured electrochemically by the aid of β″-alumina as a solid electrolyte. The distribution ratio of Cu increases with decreasing partial pressure of CO2. This implies that the activity coefficient of CuO0.5 in Na2CO3 slag is lowered rapidly as the partial pressure of CO2 is diminished. Furthermore, a relation has been discussed between the oxygen partial pressure calculated from the oxygen content in the bulk of molten copper which can be determined experimentally and that at the slag-metal interface which regulates essentially the distribution ratios of Sb and Cu.
Original language | English |
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Pages (from-to) | 175-183 |
Number of pages | 9 |
Journal | Materials Transactions, JIM |
Volume | 30 |
Issue number | 3 |
DOIs | |
Publication status | Published - 1989 |
Externally published | Yes |
Keywords
- antimony
- copper
- distribution ratio
- oxygen partial pressure
- partial pressure of carbon dioxide gas
- sodium carbonate flux
- sodium carbonate slag
ASJC Scopus subject areas
- Engineering(all)