This paper reports results of studies on the influence of the crystallographic mineral structure on the process of pyrite and marcasite leaching. Kinetic studies show that the crystallographic structure of minerals like FeS2 type does not influence the efficiency of the process.

The oxidation of ferrous iron and elemental sulfur by Thiobacillus ferrooxidans that was absorbed and unabsorbed onto the surface of sulfur prills was studied. Unadsorbed sulfur-grown cells oxidized ferrous iron at a rate that was 3 to 7 times slower than that of ferrous iron-grown cells, but sulfur-grown cells were able to reach the oxidation rate of the ferrous iron-adapted cells after only 1...

Oxidation of ferrous iron in acid solutions is an important reaction producing soluble ferric iron. The oxidizing property makes the ferric ion one of the most useful reagents in hydrometallurgy. The ferrous iron oxidation kinetics of Thiobacillus ferrooxidans growing in batch culture was examined. T. ferrooxidans oxidized ferrous iron at pH 1.5 in the presence of oxygen and utilized carbon dio...

The oxidation of a pure pyrite by Thiobacillus ferrooxidans is not really a constant phenomenon; it must be considered to be more like a succession of different steps which need characterization. Electrochemical studies using a combination of a platinum electrode and a specific pyrite electrode (packed-ground-pyrite electrode) revealed four steps in the bioleaching process. Each step can be ide...

In spite of the environmental and commercial interests in the bacterial leaching of pyrite, two central questions have not been answered after more than 35 years of research: does Thiobacillus ferrooxidans enhance the rate of leaching above that achieved by ferric sulfate solutions under the same conditions, and if so, how do the bacteria affect such an enhancement? Experimental conditions of p...