Study of Zinc Leaching of EAF Flue Dust Using Sodium Hydroxide

During the production of steel from Electric Arc Furnace (EAF), large amount of by-product called EAF flue dust is generated. The major proportion of flue dust is comprised of Zn (41.5 % wt.). Different phases identified by XRD analysis are zincite, franklinite and magnetite with zincite being dominant. In this study, we have performed flue dust treatment using sodium hydroxide as leaching medium. Different concentrations of alkali were used to optimize maximum recovery of Zn. XRF and Wet Chemical method were used to characterize the dust samples both before and after leaching. The optimum alkali concentration for selective leaching of zinc was found to be 4 M with a zinc recovery of 90 %.