Table of Contents
How is bioleaching used to extract copper?
Bioleaching involves the use of microorganisms to catalyze the oxidation of iron sulfides to create ferric sulfate and sulfuric acid. Ferric sulfate, which is a powerful oxidizing agent, then oxidizes the copper sulfide minerals and the copper contained is then leached by the sulfuric acid formed.
What happens to the bacteria after bioleaching?
The company simply collects the ions out of the solution after the bacteria have finished. There is a limited amount of ores. Bioleaching can be used to extract metals from low concentration ores as gold that are too poor for other technologies.
Where is bioleaching being used?
Bioleaching is used today in commercial operations to process ores of copper, nickel, cobalt, zinc and uranium, whereas biooxidation is used in gold processing and coal desulfurization.
What does bioleaching produce?
Bioleaching. Certain bacteria can break down ores to produce an acidic solution containing copper(II) ions. The solution is called a leachate and the process is called bioleaching . Bioleaching does not need high temperatures, but it produces toxic substances, including sulfuric acid, which damage the environment.
Who invented bioleaching?
Gaius Plinius Secundus
One of the first reports where bioleaching might have been involved in the mobilization of metals is given by the Roman writer Gaius Plinius Secundus (23 – 79 A.D.). In his work naturalis historiae libris XXXVII on natural sciences , Plinius describes how copper minerals are obtained using a leaching process.
What is true bioleaching?
Explanation: Microbially catalyzed redox reaction leads to metal mobilization that is known as bioleaching. The metal oxidizing bacteria takes in electrons from the metals and leaves behind oxidized metal that causes metal mobilization.
What organisms use bioleaching?
8 Bioleaching for bioremediation
| Domain | Organism | Main leaching agent |
|---|---|---|
| Bacteria | Crenothrix sp. | Ferric iron |
| Galionella sp. | Ferric iron | |
| Leptospirillum ferroxidants | Ferric iron | |
| Leptothrix discophora | Ferric iron Sulfuric acid |
What are the disadvantages of bioleaching?
| ADVANTAGES | DISADVANTAGES |
|---|---|
| Bioleaching is in general simpler and cheaper to operate and maintain than traditional processes. | The bacterial leaching process is very slow compared to other methods. |
When was bioleaching invented?
1947
ferrooxidans. This bacterium was first isolated in 1947 by Colmer and Hinkle [1] from acid coal mine drainage. Morphologically the cells are identical to T. thiooxidans, but they differ from the latter by the much slower course of the oxidation of elemental sulfur.
How does the leaching process work in bioleaching?
The ore remains in its natural state while the leaching process takes place. Water that contains thiobacillus is pushed through drilled passageways within the ore. The leach fluid is then stored until it is time for metal recovery. What’s next for bioleaching?
How is bioleaching used to extract precious metals?
About 20 percent of the world’s extracted copper comes from bioleaching. Bioleaching is the use of bacterial microorganisms to extract precious metals, such as gold, from ore in which it is embedded.
How is bioleaching of non sulfidic ores accomplished?
Bioleaching of non-sulfidic ores by layering of waste sulfides and elemental sulfur, colonized by Acidithiobacillus spp., has been accomplished, which provides a strategy for accelerated leaching of materials that do not contain sulfide minerals.
What’s the difference between direct and indirect bioleaching?
Direct v. Indirect Bioleaching Direct bioleaching uses minerals that are easily receptive to oxidation to create a direct enzymatic strike using the microorganisms to separate the metal and the ore. In indirect bioleaching, microorganisms are not in direct contact with minerals during the process.