Which bacteria is used for gold bioleaching?

Bioleaching can involve numerous ferrous iron and sulfur oxidizing bacteria, including Acidithiobacillus ferrooxidans (formerly known as Thiobacillus ferrooxidans) and Acidithiobacillus thiooxidans (formerly known as Thiobacillus thiooxidans). As a general principle, Fe3+ ions are used to oxidize the ore.

What kind of microorganisms are used in bioleaching?

Acidithiobacillus ferrooxidans, Acidithiobacillus caldus, Acidithiobacillus thiooxidans, and Acidithiobacillus ferrivorans are the well-known and widely studied microorganism for bioleaching due to their capability to oxidize the sulfidic minerals (Johnson, 2014).

How are microorganisms involved in biomining?

Biomining is the process of using microorganisms (microbes) to extract metals of economic interest from rock ores or mine waste. Biomining techniques may also be used to clean up sites that have been polluted with metals. Some microbes can oxidize those metals, allowing them to dissolve in water.

What is biomining cite an example?

The use of microorganisms in mineral processing technology is called biomining. Bioleaching, biooxidation, bioflotation and bioremediation are examples of technologies applied in biomining. Most microorganisms involved in this process are acidophilic, autotrophic and lithotrophic.

Which is more efficient bioleaching or microbial ore leaching?

16.6A: Microbial Ore Leaching. Microbial ore leaching is the process in which microorganisms are used to extract metals from ores. Key Points. Bioleaching is cheaper than chemical extraction, safer for the environment, and more efficient in extracting metals with low concentration in ores.

How does bioleaching improve the process of metal recovery?

Although there is no need for the cells attachment to the solid surface of the metals in the indirect mechanism, the process efficiency can be improved by locally increasing the concentration of the leaching agents (H 2 SO 4 ) on the solid surface as a result of the microbial biofilm formation (Gu et al., 2018).

Which is more solubilized gold or silver in bioleaching?

Microbial leaching of refractory precious metal ores to enhance recovery of gold and silver is one of the most promising applications. Gold is obtained through bioleaching of arsenopyrite/pyrite ore and its cyanidation process. Silver is more readily solubilized than gold during microbial leaching of iron sulphide.

Why are microorganisms used in mineral leaching?

Microbial ore leaching (bioleaching) is the process of extracting metals from ores with the use of microorganisms. This method is used to recover many different precious metals like copper, lead, zinc, gold, silver, and nickel. Microorganisms are used because they can: