2004 Volume 45 Issue 9 Pages 2851-2856
As a fundamental study to develop a new process for eliminating detrimental elements and for recovering valuable ones from secondary Cu-Fe base alloys with a considerably high content of arsenic, both the phase relations in a miscibility gap of the Cu-Fe-As system saturated with carbon and the distribution of some minor elements of silver, platinum, cobalt, nickel and sulfur between two phases in the miscibility gap were investigated at 1473 K by using a quenching method. The phase separation into copper-rich and iron-rich phases occurred when the Cu-Fe-As system was saturated with carbon. The arsenic content in the copper-rich phase was larger than that in the iron-rich phase, and carbon mostly distributed in the iron-rich phase. Cobalt and nickel distributed preferentially in the iron-rich phase, and platinum and sulfur distributed almost evenly in both phases, while silver mostly in the copper-rich phase. The experimental results for the phase separation and the distribution of the minor elements were discussed on the basis of activity coefficients in the copper-rich and iron-rich phases. By utilizing this phase separation, recovery of valuable silver and copper into the copper-rich phase and elimination of less valuable iron into the iron-rich phase are feasible for treating the secondary Cu-Fe-As base alloys.