Cleaner recovery of multiple valuable metals from cyanide tailings via chlorination roasting

ABSTRACT

Recovery of valuable metals is hindered by sulfur in cyanide tailings. In this work, a process for the clean recovery of multiple valuable metals through chlorination roasting was proposed. HSC software was used to find that the process of dissociation of chlorides is further accelerated by sulfur in the tailings. Experiments were carried out to study temperature variables and chlorinated agent variables. The optimum conditions were identified to be a CaCl₂ dosage of 4%, roasting temperature of 1323 K, achieved maximum recovery of 84% of Au, 71% of Ag, 72% of Cu, 92% of Pb, and 69% of Zn.

KEYWORDS:

• Cyanide tailings
• valuable metals
• simultaneous recycling
• thermodynamics research

Additional information

Funding

This work was supported by National Natural Science Foundation of China (51604135), Liupanshui Key Laboratory of Metallurgical Energy Saving, Environmental Protection and Recycling Economy (52020-2018-0304), the Science and Technology Innovation Group of Liupanshui Normol University (LPSSYKJTD201801) and the Key cultivation disciplines of Liupanshui Normol University (LPSSYZDPYXK201708).