Selenium Distribution in Copper/Copper Oxide Melts

The distribution of selenium between molten copper and copper oxide was determined in order to assess the possibility of extracting selenium out of copper metal into molten copper oxide. Samples were quenched from equilibrated oxide and metal layers and examined by chemical analysis. The distribution coefficient (mass% Se in Cu2O/mass% Se in Cu) at 1280°C was found to be 2.3; the activity coefficient of Cu2Se in Cu2O was estimated to be 9.6. Examination of polished sections showed that copper oxide precipitated from the copper phase. Selenium precipitated as Cu2Se and, in copper samples, was often associated with the exsolved Cu2O. The distribution coefficient is too small to permit the practical application of extraction of selenium from copper metal into copper oxide.