Bioleaching of sphalerite by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans cultured in 9K medium modified with pyrrhotite

Abstract

Elective culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in 9K medium modified with pyrrhotite was studied. Bioleaching of flotation concentrate of sphalerite by the selected bacteria was carried out. The results show that the microorganisms cultured by pyrrhotite are a mixture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans, of which the capability to oxidize ferrous to ferric irons is enhanced by the high mass ratio of Fe to S in pyrrhotite. Three pyrrhotite samples were separated into various parts with corresponding S/Fe ratios by magnetic separation and were used to culture the elective bacteria as the substrate. The association of the cultures could provide a more rapid and complete oxidation of sphalerite than that of bacteria cultivated by conventional methods.

Keywords

bioleaching / pyrrhotite / elective culture / sphalerite

References

[1] MillerP. C., RhodesM. K., WinbyR.. Commercialization of bioleaching for base-metal extraction [J]. Minerals & Metallurgical Processing, 1999, 16(4): 42-50

[2] EhrlichH. L.. Past, present and future of bioleaching [J]. Hydrometallurgy, 2001, 59(2/3): 127-134

[3] BoonM., BrasserH. J., HansfordG.. Comparison of the oxidation kinetics of different pyrite in the presence of Thiobacillus ferrooxidans or Leptospirillum ferrooxidans [J]. Hydrometallurgy, 1999, 53(1): 57-72

[4] SandW., RhodeK., SobotkeB.. Evaluation of Leptospirillum ferrooxidants for leaching [J]. Appl Environ Microbiol, 1992, 58(1): 85-92

[5] LUO Lian-ming, WANG Jun, XU Jing. Study on methods of improving bacterial leaching velocity of gold ores [J]. Conservation and Utilization of Mineral Resources, 1994(4): 40–43. (in Chinese)

[6] GarciaJ. O., MighamB. J., TuovimenO.. Sphalerite oxidation by Thiobacillus ferrooxidans and thiobacillus thiooxidans [J]. Can J Microbiol, 1995, 41: 578-584

[7] KonishiY., KuboH., AsiaS.. Bioleaching of zinc sulfide concentration by Thiobacillus ferrooxidants [J]. Biotechnol Bioeng, 1992, 39: 66-74

[8] ChoiW. K., TormaA. E., OhilineR.. Electrochemical aspects of zinc sulphide leaching by Thiobacillus ferrooxidans [J]. Hydrometallurgy, 1993, 33(1/2): 137-152

[9] LanZ.-y., HuY.-h., LiuJ.-s., WangJun.. Solvent extraction of copper and zinc from bioleaching solutions with LIX984 and D2E [J]. Journal of Central South University of Technology, 2005, 12(1): 45-49

[10] QinW.-q., LanZ.-y., LiW.-zhong.. Recovery of zinc from low-grade zinc oxide ores by solvent extraction [J]. Journal of Central South University of Technology, 2003, 10(2): 98-102

[11] LiangD.-y., HeG.-w., ZouNi.. The isomeromorphism of pyrrhotite and its treatment feature differentia [J]. Journal of Guangdong Nonferrous Metals, 1997, 7(1): 1-5

[12] XiaX.-hui.. A kind of pyrrhotite from pyrite deposits in east Liaoning rift mineralogical implications [J]. Geology of Chemical Minerals, 1996, 18(4): 263-270

[13] JiS., ShangZ. C.. The determination of Zn²⁺ in compound of Zn²⁺ and Fe²⁺ by EDTA titration [J]. Shandong Chem Ind, 2000, 29: 40-41

[14] KaramanevD. G., NikolovL. N., MamatarkovaV.. Rapid simultaneous quantitative determination of ferric and ferrous ions in drainage waters and similar solutions [J]. Mineral Engineering, 2002, 15(5): 341-346

[15] VegliòF., BeolchiniF., NardiniA., ToroL.. Bioleaching of a pyrrhotite ore by a sulfooxidans strains: Kinetic analysis [J]. Chemical Engineering Science, 2000, 55(4): 783-795

[16] LI Hong-mei. Bioleaching of pyrrhotite bearing nickel—A review [J]. Hydrometallurgy, 1999(3): 8–12. (in Chinese)

[17] FowlerT. A., CrundwellF. K.. Leaching of zinc sulfide by thiobacillus ferrooxidans: Experiments with a controlled redox potential indicate no direct bacterial mechanism [J]. Appl Environ Microbiol, 1998, 64(10): 3570-3575

[18] FowlerT. A., CrundwellF. K.. Leaching of zinc sulfide by thiobacillus ferrooxidans: Bacterial oxidation of the sulfur product layer increases the rate of zinc sulfide dissolution at high concentration of ferrous ions [J]. Appl Environ Microbiol, 1999, 65(12): 5285-5292