Study On Separation Of Zinc And Iron From Electric Arc Furnace Dust And Preparation Of Ni-Zn Ferrite

As scrap production increasing and iron ore reserves gradually decreasing,electric arc furnace steelmaking will be used extensively to maintain huge steel production capacity.A large amount of electric arc furnace dust(EAFD)will produce in the electric arc furnace steelmaking process.EAFD contains a large amount of iron and various valuable elements,such as zinc,magnesium,manganese et al.Therefore,how to recycle the EAFD have attracted many attentions in recent years.Under this background,this paper explores the feasibility of preparing ferrite by using EAFD,iron scale and Ni Cl2·6H2O as raw material and successfully prepared Ni-Zn ferrite.In addition,the effects of SiO₂ content,the amount of Ni added and heat treatment on the synthesized and magnetic properties of the Ni-Zn ferrite were discussed and the results showed as follows:(1)The quality of SiO₂ and NiCl2·6H2O in EAFD has a significant impact on the magnetic properties of Ni-Zn ferrite synthesized by EAFD.The lower the SiO₂ content in EAFD,the higher the magnetic properties of the ferrite prepared.In addition,as the content of Ni Cl2·6H2O increases,the magnetic properties of the ferrites prepared first increase and then decrease,reaching the maximum when the mass ratio of EAFD to Ni Cl2·6H2O is 1 : 0.9.(2)Roasting after mixing NaOH/CaO and EAFD is helpful to the extraction of Zn²⁺ in EAFD.The higher the content of NaOH,the higher the leaching rate of Zn²⁺.Considering the economy,the mass ratio of NaOH to EAFD is 1 : 1 as the optimal condition.The higher the content of CaO,the higher the leaching rate of Zn²⁺.But the leaching solution contains a large amount of Ca²⁺,which has an adverse effect on the preparation of Ni-Zn ferrite and its magnetic properties.Therefore,the optimum condition is that the ratio of CaO to Fe in EAFD is 1.3 : 1.(3)The content of doped Ni²⁺ and the calcination temperature of the prepared samples have a significant impact on the preparation of Ni-Zn ferrite and its magnetic properties.As the molar ratio of Ni²⁺ to Zn²⁺ increases,the magnetic properties of the prepared samples increase first and then decrease.When the molar ratio of Ni²⁺ to Zn²⁺ is 6 : 4,the magnetic properties of the prepared samples are the best.When the calcination temperature is above 700°C,as the calcination temperature increases,the Ni-Zn ferrite exhibits better magnetic properties.In this study,the soft magnetic material Ni-Zn ferrite with good magnetic performance was synthesized from EAFD successfully,which realized the high value-added utilization of electric furnace dust and provided a new idea for the efficient utilization of metallurgical dust.