Bacterial leaching of a sulfide ore by Thiobacillus ferrooxidans and Thiobacillus thiooxidans: I. shake flask studies

Journal Article · Mon Jun 20 04:00:00 EDT 1988 · Biotechnol. Bioeng.; (United States)

DOI:https://doi.org/10.1002/bit.260320116· OSTI ID:7141232

Lizama, H; Suzuki, I

Bacterial leaching of a sulfide ore containing pyrite, chalcopyrite, and sphalerite was studied in shake flask experiments using Thiobacillus ferrooxidans and Thiobacillus thiooxidans strains isolated from mine sites. The Fe/sup 2 +/-grown T. ferrooxidans isolates solubilized sphalerite preferentially over chalcopyrite leaching 7-10% Cu, 68-76% Zn, and 10-22% Fe from the ore in 18 days. The sulfur-grown T. thiooxidans isolates leached Zn much more slowly and very little Fe, with a Cu-Zn extraction ratio twice the value obtained with T. ferrooxidans. The ore-adapted T. ferrooxidans started solubilizing Cu and Zn without a lag period. The ore-adapted T. thiooxidans extracted Cu as well as T. ferrooxidans, but the extraction of Zn or Fe was still much slower in the low-phosphate medium, while in the high-phosphate medium it approached the value obtained with T. ferrooxidans. A high Cu-Zn extraction ratio of 0.34 was obtained with T. thiooxidans in the low-phosphate medium. In the mixed-culture experiments with T. ferroxidans and T. thiooxidans, the culture behaved as T. thiooxidans in the low-phosphate medium with a higher Cu-Zn extraction ratio and as T. ferrooxidans in the high-phosphate medium with a lower Cu-Zn extraction ratio. It is concluded that T. ferrooxidans and T. thiooxidans solubilize sulfide minerals by different mechanisms.

• Research Organization: Univ. of Manitoba, Winnipeg (Canada)
• OSTI ID: 7141232
• Journal Information: Biotechnol. Bioeng.; (United States), Journal Name: Biotechnol. Bioeng.; (United States) Vol. 32:1; ISSN BIBIA
• Country of Publication: United States
• Language: English

Related Subjects

510200* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
BACILLUS
BACTERIA
BIODEGRADATION
CHEMICAL REACTIONS
COPPER
DECOMPOSITION
DISSOLUTION
ELEMENTS
IRON
LEACHING
METALS
MICROORGANISMS
MINERALS
SEPARATION PROCESSES
SULFIDE MINERALS
SULFUR-OXIDIZING BACTERIA
THIOBACILLUS FERROXIDANS
TRANSITION ELEMENTS
ZINC