Recovery iron from zinc leaching residues by reduction roasting and magnetic separation process

Based on the process mineralogy,the zinc ferrite was decomposed into zinc oxide and ferroferric oxide by reduction roasting,and then recovery iron by magnetic separation.The effects of roasting temperature,roasting time and usage of reducing agent on the decomposition rate of zinc ferrite and recovery rate of iron were investigated.The results show that the decomposition rate of zinc ferrite reaches 72.05% and the recovery of iron reaches 91.79% after roasted at 950 ℃ for 1 h in 10% or 5% reducing agent.The iron concentrate grade only reaches 50%.The agglomeration of particles in the process of roasting and magnetic separation leads to the lower grade.