Innovative methodology for comprehensive utilization of high iron bearing zinc calcine

An innovative method for comprehensive utilization of high iron bearing zinc calcine was proposed, and the recovery of zinc and iron was studied. The thermodynamic analysis and roasting experiments were firstly carried out to study the decomposition of ZnFe2O4 which could be selectively converted to ZnO and Fe3O4 under optimized roasting conditions. The roasted zinc calcine was then subjected to low acid leaching followed by magnetic separation. The effects of operating conditions on the recovery of zinc and iron and the mineralogical changes during the process were investigated. The results showed that about 91% of zinc was extracted and most of iron was separated into the leach residue as magnetite at 40 degrees C for 10 min with 90 g/L H2SO4 and liquid/solid ratio at 10 mg/L, while about 91% of iron was reported to the concentrate with iron grade of 45.5% after a magnetic separation at 35 kA/m. Besides, lead impurity was transformed, separated and concentrated into the tailing in the form of PbSO4 and Pb. (C) 2015 Elsevier B.V. All rights reserved.