Effect of anions on selective solubilization of zinc and copper in bacterial leaching of sulfide ores.
Bacterial leaching of sulfide ores using Thiobacillus ferrooxidans, Thiobacillus thiooxidans, or a combination of the two was studied at various concentrations of specific anions. Selective zinc and copper solubilization was obtained by inhibiting iron oxidation without affecting sulfur/sulfide oxidation. Phosphate reduced iron solubilization from a pyrite (FeS(2))-sphalerite (ZnS) mixture without significantly affecting zinc solubilization. Copper leaching from a chalcopyrite (CuFeS(2))-sphalerite mixture was stimulated by phosphate, whereas chloride accelerated zinc extraction. In a complex sulfide ore containing pyrite, chalcopyrite, and sphalerite, both phosphate and chloride reduced iron solubilization and increased copper extraction, whereas only chloride stimulated zinc extraction. Maximum leaching obtained was 100% zinc and 50% copper. Time-course studies of copper and zinc solubilization suggest the possibility of selective metal recovery following treatment with specific anions.
Harahuc
L
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Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
Lizama
H M
HM
Suzuki
I
I
D013856:Acidithiobacillus thiooxidans / Q000378:metabolism; D000838:Anions; D001709:Biotechnology; D003300:Copper / Q000302:isolation & purification*; D007501:Iron / Q000302:isolation & purification; D007700:Kinetics; D008903:Minerals / Q000302:isolation & purification; D008906:Mining; D012995:Solubility; D013440:Sulfides / Q000302:isolation & purification; D013855:Thiobacillus / Q000378:metabolism; D015032:Zinc / Q000302:isolation & purification*
D000838:Anions; D008903:Minerals; D013440:Sulfides; C012819:chalcopyrite; C011342:pyrite; D003300:Copper; D007501:Iron; D015032:Zinc