Minerals Engineering, Vol.86, 34-42, 2016
Comprehensive recovery of the components of ferritungstite base on reductive roasting with mixed sodium salts, water leaching and magnetic separation
Ferritungstite ores have great commercial value because of the huge reserve and high content of W, Mo and Fe. But their economic recovery has long been a challenge due to its complex mineralogy and heterogeneous. The current study investigated how reductive roasting of ferritungstite ores with mixed sodium salts affected the phase evolution of W, Mo and Fe through Micro-area XRD and Powder XRD, with the goal of comprehensive transformation of ferritungstite. Reductive roasting with mixed sodium salts at 800 degrees C transformed ferritungstite to Na2WO4 and magnetite (Fe3O4), which were easily recovered by water leaching and magnetic separation. Furthermore, a lot of pores and gaps rather than sintering or agglomeration was observed in the ore particles after roasting by SEM-EDS, which was beneficial for the water leaching of W and Mo. As a result, 96.40% of W and 96.64% of Mo were extracted after water leaching, while an iron concentrate with an Fe content of 55.65% and recovery of 83.30% was obtained after magnetic separation. These results suggested such process would be applicable to the comprehensive recovery of valuable metals from ferritungstite ores, as well as similar tungsten ores and scraps. (C) 2015 Elsevier Ltd. All rights reserved.