Recovery of zinc and iron from high iron-bearing zinc calcine by selective reduction roasting

• The ZnFe2O4 was selectively converted to ZnO and Fe3O4 by reduction roasting.
• About 92.6% Zn was extracted and most of iron reported into residue as magnetite.
• More than 90% Fe can be recovered from the residue by magnetic separation.

A novel method to recover zinc and iron from high iron-bearing zinc calcine by reduction roasting-low acid leaching-magnetic separation was proposed. The effects of roasting and leaching conditions were investigated and their optimum conditions were established. Meanwhile, the mineralogical changes during the processes were characterized by XRD, VSM, SEM and LPSA. The results show the ZnFe2O4 in the calcine was decomposed into ZnO and Fe3O4, and about 92.6% Zn was extracted from the roasted calcine with reporting most of iron as magnetite into the residue. Finally, more than 90% Fe was recovered from the residue by magnetic separation method.