Influence of silver ions on bioleaching of cobalt from spent lithium batteries

摘要

The influence of silver ions (Ag~+) on the bioleaching of cobalt from spent lithium batteries using Acidithio-bacillus ferrooxidans [A ferrooxidans) bacteria was investigated. The best effect was observed at Ag~+ concentration of 0.02 g/L, and the amount of leached cobalt was 98.4% in a period of 7 days, whereas in the absence of Ag~+, the amount of leached cobalt was only 43.1%. Based on the results of SEM, XRD and EDX investigation, it is deduced that Ag~+ first reacted with cobalt to form AgCoO_2 as an intermediate. A mechanism that is based on catalytic interactions is proposed to explain the enhanced leaching of Co using A ferrooxidans.