Electrogenerative leaching for sphalerite-MnO2 in the presence of
Acidithiobacillus thiooxidans
(1. College of Chemistry and Biological Engineering, Changsha University of Science and Technology,
Changsha 410004, China;
2. School of Resources Processing and Bioengineering, Central South University, Changsha 410083, China;
3. Metallurgic Engineering College, Hunan Industrial University, Zhuzhou 412000, China)
Changsha 410004, China;
2. School of Resources Processing and Bioengineering, Central South University, Changsha 410083, China;
3. Metallurgic Engineering College, Hunan Industrial University, Zhuzhou 412000, China)
Abstract: A dual cell system was used to study the electrogenerative leaching sphalerite-MnO2 in the presence and absence of Acidithiobacillus thiooxidans (A. thiooxidans). The polarization of anode and cathode, and the relationship between the electric quantity (Q) and some factors, such as the dissolved rate of Zn2+ and Fe2+, and the time in the bio-electro-generating simultaneous leaching (BEGL) and electro-generating simultaneous leaching (EGL) were studied. A three-electrode system was applied to studying anodic and cathodic self-corrosion current, which was inappreciable compared with the galvanic current between sphalerite and MnO2. The results show that the dissolved Zn2+ in the presence of A. thiooxidans is nearly 43% higher than that in the absence of A. thiooxidans; the electrogenerative quantity in the former is about 150% more than that in the latter. The accumulated sulfur on the surface of sulfides produced in the electrogenerative leaching process can be oxidized in the presence of A. thiooxidans, and the ratio of biologic electric quantity reaches 27.9% in 72 h.
Key words: A. thiooxidans; electrogenerative leaching; sphalerite