Activities of liquid Fe-As and Fe-Sb alloys saturated with carbon

A solid iron base alloy of the so-called furnace residue is often formed as a by-product in reduction smelting of lead sinter and scraps with high contents of arsenic and antimony. The use of phase separation into a liquid iron-rich alloy and a liquid lead-rich alloy in lead-iron-arsenic and lead-iron-antimony systems saturated with carbon at relatively low temperatures of about 1200°C was proposed in a new process for treating the furnace residue to recover valuable elements into the lead-rich alloy and fix toxic arsenic into the iron-rich alloy. As a fundamental study for the proposed process, the activity coefficients and interaction parameters of the Fe-As and Fe-Sb systems saturated with carbon at 1200°C were de- rived in this study, based on the determined phase relations in the Fe-Pb-As and Fe-Pb-Sb systems saturated with carbon.