Control method of chalcopyrite passivation in bioleaching
(1. School of Materials and Metallurgy, Northeastern University, Shenyang 110819, China;
2. College of Science, Northeastern University, Shenyang 110819, China;
3. College of Resource and Civil Engineering, Northeastern University, Shenyang 110819, China)
2. College of Science, Northeastern University, Shenyang 110819, China;
3. College of Resource and Civil Engineering, Northeastern University, Shenyang 110819, China)
Abstract: Passivation is a common phenomenon on the surface of chalcopyrite in the process of bioleaching. The ordinary leaching and strengthening leaching by adding glass beads were carried out. The results show that the passivation of chalcopyrite was greatly weakened in strengthening leaching due to the change of leaching conditions. The copper leaching efficiency was increased from 50% to 89.8% through adding beads. The SEM and X-ray diffraction (XRD) analyses illustrate that there are few jarosite precipitates and weak passivation on the surface of chalcopyrite in strengthening leaching. In contrast, there are thick and compact jarosite precipitate and obvious passivation in ordinary leaching, which hinders further dissolution of chalcopyrite.
Key words: passivation; chalcopyrite; bioleaching; leaching; jarosite