Liquid Immiscibility in Fe-Cu-B-C System

摘要

The metal in the shredder dust, which is produced from scrapped automobiles and home electric appliances by shredding and sorting, is mainly composed of iron and copper. It is more desirable to reuse as ferrous and cupreous resources by separating iron and copper. In the present work, the phase separation of iron and copper in the Fe-Cu-B and Fe-Cu-B-C systems is investigated at 1 523 K and 1 425 K. In the Fe-Cu-B system, the copper content of Fe-rich phase and the iron content of Cu-rich phase at 1 523 K are 4.60 mass% and 5.30 mass%, respectively, in the case of [mass%B]_((in Fe))=2.90.The contents are about 1 to 2 mass% lower than those at 1 873 K. In the Fe-Cu-B-3mass%C system, the copper content of the Fe-rich phase and the iron content of the Cu-rich phase are lower than those in the Fe-Cu-B system. The carbon addition widens the miscibility gap of iron and copper and is more effective for the separation. By the boron and/or carbon additions, it is almost possible to recover more than 80% of copper from Fe-20mass%Cu alloy.