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...

the oxidation of ferrous iron (fe2+) in solution using acidithiobacillus ferrooxidans has industrial applications exclusively in the regeneration of ferric iron (fe3+) as an oxidizing agent for the removal of hydrogen sulfide from waste gases, desulfurization of coal, leaching of non-ferrous metallic sulfides and treatment of acid mine drainage. the aim of this investigation was to increase the...

The oxidation of ferrous iron by Acidithiobacillus ferrooxidans in the pH range 2.5–7.0 was characterized. In order to measure the rate of bacterial oxidation of ferrous iron with A. ferrooxidans in this high pH range, a novel experimental methodology was developed. The results showed that the inhibition of ferrous iron oxidation activity by A. ferrooxidans observed at pH values above 3.0 is pa...

The oxidation of ferrous iron (Fe2+) in solution using Acidithiobacillus ferrooxidans has industrial applications exclusively in the regeneration of ferric iron (Fe3+) as an oxidizing agent for the removal of hydrogen sulfide from waste gases, desulfurization of coal, leaching of non-ferrous metallic sulfides and treatment of acid mine drainage. The aim of this investigation was to increase the...

The suitability of hemp fibres as green support material for immobilization of Acidithiobacillus ferrooxidans cells in ferrous iron bio-oxidation process was investigated. A series of experiments were carried out in shake flasks and bioreactor for both cell immobilization and iron bio-oxidation. In flask experiments, five successive batch colonization cycles resulted in 6-fold increase...

Many bituminous coal mine effluents contain, along with other ions, high concentrations of ferrous iron. This is brought into solution by sulfuric acid produced by the oxidation of sulfuritic material, possibly iron sulfides in part, occurring with bituminous coal (Leathen et al., 1952). The ferrous iron is oxidized by bacteria to the ferric state at a more rapid rate than can be accounted for ...

Mechanisms of superoxide.O2--generating systems on the pro-oxidant effect of iron from various sources were studied. Reaction mixtures were prepared with distilled water, oil emulsion, or meat homogenates. Free ionic iron (ferrous and ferric), ferritin and hemoglobin (Hb) were used as iron sources, and KO2 and xanthine oxidase (XOD) systems were used to produce .O2-. Thiobarbituric acid reactiv...

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...

Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

Oxidation of ferrous iron was studied with the anaerobic phototrophic bacterial strain BS-1. Based on morphology, substrate utilization patterns, arrangement of intracytoplasmic membranes and the in vivo absorption spectrum, this strain was assigned to the known species Rhodomicrobium vannielii. Also, the type strain of this species oxidized ferrous iron in the light. Phototrophic growth of str...