Abstract:Zinc oxide dust, produced by pyrometallurgical fuming volatilization method after zinc hydrometallurgy and lead pyrometallurgical slag treatment, mainly contains zinc, iron, as well as indium, germanium and other rare metals, which has a high recovery value. Conventional zinc oxide dust is treated by two-stage acid leaching process. Usually, only one rare metal can be recovered singly, which cannot meet the requirements of raw material change and smelting in enterprises. Taking zinc oxide dust containing indium and germanium as raw material, indium and germanium were leached step by step by adjusting acidity of the reaction process based on the different leaching characteristics of indium and germanium. The separation and extraction of indium and germanium from zinc oxide dust can be realized through the different extraction characteristics of indium and germanium. The results show that after three-stage neutral leaching, weak acid leaching, and high acid enhanced leaching, content of indium and germanium in leaching solution is about 2 mg/L and 60 mg/L, which can be used for subsequent precipitation and recovery of germanium. The content of indium and germanium in low acid leaching solution is about 280 mg/L and 70 mg/L. After subsequent neutralization precipitation, indium is enriched to about 10 075 g/t. Refined indium product and germanium-containing raffinate can be obtained by leaching, extraction, and electrodeposition of neutralizing residue, and the raffinate is returned to neutral leaching, which achieves the purpose of separation and extraction of indium and germanium, and realizes the comprehensive utilization of resources.