The
present work describes a research approach to the aerobic bioleaching of U (IV)
ores. Three strains (Acidithiobacillus sp.) isolated from sulfur springs in
Ramsar province, Iran and nucleotide sequences of gene fragments of examined
Acidithiobacillus sp. strains were recorded in NCBI .Then, uranium bioleaching
experiment carried out with native bacteria in different pulp densities.
In
following, the performance of the isolates was improved progressively by
optimizing the pH and initial iron concentrations. The results showed that total
uranium extraction was achieved with 100% efficiency using native isolated
Acidithiobacillus sp. strain FJ2 in 2.5, 5, 7.5 and 10% pulp densities of the
ore. Whereas, the isolates could leach the U (VI) with 68% efficiency at 12.5%
ore pulp density.
In addition, Acidithiobacillus sp. strain FJ1 leaded to 100%
uranium extraction at 2.5% pulp density and 59%at 5% pulp density of the ore.
As well, determined optimized values showed that initial ferrous iron
concentration at 2.5 g/L and initial pH at 2, gives maximum uranium extraction
yields. This is very promising results since, the native isolated strains
especially Acidithiobacillus sp. strain FJ2 can be used as a capable bacteria
in uranium extraction process.Read More...