The pre-bio-oxidation and its effect on the leaching process of low-grade copper ore in percolation columns

Abstract

The results of laboratory studies intended to extract copper from substandard copper raw materials in percolators are presented in this work. The results of chemical elemental analysis, X-ray phase analysis and chemical phase analysis for the copper and iron forms in the ore are also presented herein. The efficiency of sulfuric acid and bacterial leaching in percolation columns was compared. When standard sulfuric acid leaching was used, copper extraction into the solution was 49.85%, whereas in bacterial oxidation (by chemolithotrophic bacteria - Thiobacillus thiooxidans, oxidizing sulfur and iron compounds) - 74.81% during 60 days of the experiment. The redox potential values are presented for standard sulfuric acid and bacterial leaching of copper ore, which correlate with copper yield. It was found as a result of the research that the use of bacterial technology provides deeper processing of copper ore due to the oxidation of copper sulfide minerals.