(中南大学 冶金与环境学院，长沙 410083)
摘 要: 工业湿法炼锌过程中会产生大量锌浸出渣，选择性回收其中的锌成为了研究热点。本文通过硫酸铵与锌浸出渣混合焙烧后水浸实现其中的铁和锌分离，从而实现资源综合利用。通过研究确定了最优焙烧条件，即硫酸铵与锌浸出渣质量比为1.30、焙烧温度为650 ℃、焙烧时间为240 min。结果表明，硫酸铵与铁酸锌在325~425 ℃时，反应生成(NH4)2Zn(SO4)2和NH4Fe(SO4)2；然后在500~650 ℃下，(NH4)2Zn(SO4)2和NH4Fe(SO4)2各自分解生成ZnSO4和Fe2(SO4)3，其中Fe2(SO4)3继续分解生成Fe2O3和SO3。在最优条件下所得焙烧产物经水浸后，锌的浸出率达到93.53%，而铁的浸出率为5.97%，实现了锌和铁的有效选择性分离。
关键字: 锌浸出渣；铁酸锌；硫酸铵焙烧；锌；铁
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:In the process of industrial hydrometallurgical zinc smelting, a large amount of zinc leaching residue was produced, and the selective recovery of zinc has become a research hotspot. In this paper, ammonium sulfate and zinc leaching residue were mixed and roasted and then water-leached to achieve the separation of iron and zinc, thereby achieving comprehensive utilization of resources. The optimal roasting conditions are determined through experiments, that is, the mass ratio of ammonium sulfate to zinc leaching residue is 1.3, the roasting temperature is 650 ℃, and the roasting time is 240 min. The results show that ammonium sulfate and zinc ferrite will react to form (NH4)2Zn(SO4)2 and NH4Fe(SO4)2 at 325-425 ℃, and then at 500-650 ℃, (NH4)2Zn(SO4)2 and NH4Fe(SO4)2 respectively decompose to produce ZnSO4 and Fe2(SO4)3, of which Fe2(SO4)3 continues to decompose to produce Fe2O3 and SO3. Under the optimal conditions, the leaching rate of zinc in the calcined product after water leaching reaches 93.53% and that of iron is 5.97%, thus realizing the effective and selective separation of zinc and iron.
Key words: zinc leaching residue; zinc ferrite; ammonium sulfate roasting; zinc; iron
