Recovery of valuable metals from zinc leaching residue by sulfate roasting and water leaching

作者：Guo min JIANG; Bing PENG; Yan jie LIANG; Li yuan CHAI; Qing wei WANG; Qing zhu LI; Ming HU

来源：Transactions of Nonferrous Metals Society of China (English Edition), 2017, 27(5).

DOI：10.1016/S1003-6326(17)60138-9

• zinc leaching residue
• sulfate roasting
• water leaching
• valuable metals recovery

Zinc leaching residue (ZLR), produced from traditional zinc hydrometallurgy process, is not only a hazardous waste but also a potential valuable solid. The combination of sulfate roasting and water leaching was employed to recover the valuable metals from ZLR. The ZLR was initially roasted with ferric sulfate at 640 ℃ for 1 h with ferric sulfate/zinc ferrite mole ratio of 1.2. In this process, the valuable metals were efficiently transformed into water soluble sulfate, while iron remains as ferric oxide. Thereafter, water leaching was conducted to extract the valuable metals sulfate for recovery. The recovery rates of zinc, manganese, copper, cadmium and iron were 92.4%, 93.3%, 99.3%, 91.4% and 1.1%, respectively. A leaching toxicity test for ZLR was performed after water leaching. The results indicated that the final residue was effectively detoxified and all of the heavy metal leaching concentrations were under the allowable limit.

• 单位
  中南大学