Column Leaching of Low-Grade Chalcopyrite Ores Using Thermophilic Bacteria

摘要

Low-grade porphyry copper ores containing chalcopyrite as the primary mineral was leached by two strains of acidophilic, thermophilic microbes belonging to the genus Sulfolobus. Leach tests were conducted in glass columns heated to 60 to 70C. Ores sized to minus 12/-inch plus 50-mesh were effectively leached by the thermophilic organisms, bur ores sized to minus 2-inch plus 1/2-inch resisted leaching. Decreasing the pH of the leachate to about 1.8 enhanced the copper extraction from ore with the thermophilic microbes. The bacterium Thiobacillus ferrooxidans was relatively ineffective for extracting copper from the ore.