Study on Bacteria Leaching of Sulfide Ores Properties of F. ferrooxidans, Th. thiooxidans and Th. ferrooxidans. (2)

• Published in: Japanese Journal of Limnology (Rikusuigaku Zasshi) Vol. 29; no. 1; pp. 21 - 36
• Main Authors: WATANABE, Atsumi, UCHIDA, Takeshi, FURUYA, Susumu
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society of Limnology 28.05.1968
• ISSN: 0021-5104; 1882-4897
• DOI: 10.3739/rikusui.29.21

(1). The species of the thiosulfate-oxidizing bacteria (Th. ferrooxidans) have been isolated from Frutobe mine water (Daikokuzawa, west, O. L, No. 3 loop). (2). The iron oxidation rates by F. ferrooxidans were accelerated by increasing the size of the inoculum, at inoculum of one ml per 150 ml of medium converted to the ferric state about 70% of initial Fe2+ concentrations in 11 days of incubation and at inocula of 2 ml converted to the ferric state about 99%. By increasing the size of the inoculum, up to 410 ml per 150ml of medium, converted to the ferric state 9799% in 8 days of incubation. (3). By breeding successive generations of F. ferrooxidans in culture media successively more concentrated in dissolved copper (CuSO4, solu.), the tolerance of the bacteria was increased to approximately 25 grams of the copper per liter. (4). The strain of F. ferrooxidans could oxidize elemental sulfur as well as ferrous iron, but the presence of the large amounts of elemental sulfur suppressed the iron oxidizing ability of this organism. (5). On the studies of the influence of various organic substances on the oxidation of ferrous iron by F. ferrooxidans, urea and peptone retard the oxidation of iron and the growth of bacteria at concentrations greater than 0. 2%. Glucose was able to accelerate the growth of bacteria by increasing the amounts, but retarded the oxidation of iron at concentrations greater than 0. 1%. (6). If was not evident that the strain of F. ferrooxidans utilizes thiosulfate, but Th. ferrooxidans was able to grow using thiosulfate as the energy source and Th. thiooxidans utilized a little thiosulfate. (7). Th. ferrooxidans and F. ferrooxidans could utilize chalcopyrite as a source of energy.Th. ferrooxidans leached 86 % of the copper from chalcopyrite and F. ferrooxidans leached 68% in 50 days at 26 °C on a reciprocal shaker. Th. thiooxidans had no effect on the dissolution of copper from chalcopyrite.