(中南大学 冶金科学与工程学院,长沙 410083)
摘 要: 研究硫酸体系中铅黄铁矾的形成条件,考察pH值、温度、PbSO4用量、时间和晶种浓度对铅黄铁矾形成及除铁率的影响。结果表明:当pH>0.7,温度大于75 ℃时,形成铅黄铁矾;在维持溶液pH为1.3、温度95 ℃、硫酸铅的加入量为理论量的1.2倍、晶种浓度为8 g/L、时间2.5 h的最优条件下,平均除铁率高于95%;得到的铅黄铁矾渣平均含Pb 22.47%、Fe 23.74%、Zn 1.96%;经硫酸化焙烧−水浸或直接用锌废电解液浸出锌和铁后,浸出渣含Pb均大于60%,可返回作沉矾剂,亦可作为炼铅的原料。
关键字: 铅黄铁矾;形成条件;硫酸铅;晶种
(School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China)
Abstract:The formation condition of lead jarosite was studied, the effects of pH, temperature, PbSO4 dosage, time and seed concentration on the formation condition of lead jarosite and the precipitation rate of Fe were investigated. The results show that lead jarosite form under the following conditions, as pH>0.7, temperature larger than 75 ℃. The precipitation rate of Fe is larger than 95% under the following optimum conditions, as maintaining pH range 1.3, temperature 95 ℃, 1.2 times of theoretical fraction of PbSO4, seed concentration 8 g/L. The contents of Pb, Fe and Zn in lead jarosite are 22.47%, 23.74% and 1.96%, respectively, after leaching of Zn and Fe with sulfation roasting before water leaching or zinc waste electrolyte directly, the lead content in the leaching residue is larger than 60%, can be returned to remove iron and used as raw material for lead smelting.
Key words: lead jarosite; formation condition; lead sulphate; seed