Differences of Bioleaching of Pyrites from Different Geo-Genetic Deposits by Leptospirillum ferriphilum

Abstract:

In this paper, the bioleaching behavior of three pyrites from different geological origins (high-temperature hydrothermal, low-temperature hydrothermal and coal sedimentary) by L. ferriphilum was studied. The internal structure of three pyrite samples were investigated using optical microscope. The results show that the physical characteristics and internal structures of pyrites from different geological origins are different, and this causes the divergences of their bioleaching behavior. High-temperature hydrothermal pyrite (n-type semiconductor tested) is not almost dissolved and the leaching rate is only 0.58%, while the leaching rate of low-temperature hydrothermal pyrite and coal sedimentary pyrite (both of p-type semiconductor tested) are 15.25% and 27.50% respectively. The Leica optical microscope test of p-type semiconductor pyrites indicates that coarse particle of low-temperature hydrothermal pyrite is crystallized well and sedimentary pyrite consists of fine-grained crystal with poor crystallinity. This was suggested to cause the divergences of the bioleaching rate of both p-type semiconductor pyrites. In view of mineralogy, the semiconductive type of pyrite is the primary factor affecting its bioleaching. Furthermore, the different internal structure of pyrites will further have an influence on bioleaching for the same semiconductive type.Key words: pyrite; bioleaching; L. ferriphilum; geo-genetic

• Periodical: Advanced Materials Research (Volume 825)
• Pages: 326-330
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.825.326
• Online since: October 2013
• Authors: Xun Zhang, Guo Hua Gu, Ke Ting Hu, Guan Zhou Qiu
• Keywords: Bioleaching, Geo-Genetic, L. ferriphilum, Pyrite

References

[1] R. Liu, A. L. Wolfe, D. A. Dzombak, C. P. Horwitz, 2008. Electrochemical study of hydrothermal and sedimentary pyrite dissolution. Applied Geochemistry 23 (9), 2724~2734.

DOI: 10.1016/j.apgeochem.2008.06.005

[2] B. Moon, H. J. Brasser, G. S. Hansford, J. J. Heijnen, 1999. Comparison of the oxidation kinetics of different pyrites in the presence of Thiobacillus ferrooxidans or Leptospirillum ferrooxidans. Hydrometallurgy 53 (1), 57~72.

DOI: 10.1016/s0304-386x(99)00037-7

[3] D. F. Tu, 1984. Inclusions in minerals in the Shangbao pyrite district, Hunan. Geology comment 30 (3), 270~274.

[4] S. T. Yang, Y. F. Chang, 2003. Geological feature and genesis of Huangcha pyrite deposit in Yuping county, Guizhou. Guizhou geology 16 (1), 40~45.

[5] B. G. Xue, 2003. Discussion on geological characteristics of pyrite deposits in Yunnan and their development. Geology of chemical mineral 25 (3), 185~192.

[6] H. X. Li, D. Z. Wang, 2004. Semiconductor/solution interface of sulfide leaching process. Nonferrous metals 56 (2), 77~80.

[7] A. Ennaoui, S. Fiechter, C. Pettenkor, et al., 1993. Iron disulfide for solar energy conversion. Solar Energy Materials and Solar cells 29 (4), 289~370.

DOI: 10.1016/0927-0248(93)90095-k

[8] F. K. Crundwell, 1988. The influence of the electronic structure of solids on the anodic dissolution and leaching of semiconducting sulphide minerals. Hydrometallurgy 21 (2), 155~190.

DOI: 10.1016/0304-386x(88)90003-5

[9] X. W. Yang, Q. F. Shen, Y. X. Guo. Microbial Metallurgy. Beijing: Metallurgical Industry Press, (2003).