Fe-Cu-C系2液相分離による低品位銅スクラップからの銅の濃縮

Abstract

A mixture of iron, copper and carbon was melted in a carbon crucible at 1, 453 K. The top layer which was rich in iron and the bottom layer which was rich in copper were clearly separated in the crucible. We could thus make fundamental experiment to carry out a phase separation for copper recovery from iron scrap containing copper. One of the focuses is the effect on the phase separation and the suspension of an extra element to the Fe-Cu-C ternary system. We added Cr, Mn, Al, Si or S to Fe-Cu-C ternary system, and determined the compositions of miscibility gap at 1, 453 K under carbon saturation. In some cases scrap contains precious metal. On this account the recovery distribution ratios of precious metal were also measured.The alloy compositions on the miscibility gap in the Fe-Cu-C system are 91.1% Fe-4.7% Cu-4.2%C and 96.7%Cu-3.3% Fe. Addition of aluminum, Silicon or sulfur causes the gap to narrow. An increase in carbon solubility in the phase rich in iron reduces copper solubility, which affects recovery of copper from scrap. The relation between copper and carbon solubility in the phase rich in iron is(% Cu)=0.68 (%C) 2-7.26 (%C) +22.77Gold, silver and palladium are enriched in the phase rich in copper. Platinum distributes both phases equally. The activity coefficients of Ag, Au, Pd and Pt were estimated from the distribution ratios.