How do bioleaching and phytomining extract metals?

Bioleaching and phytomining extract metals by using bacteria and plants to absorb and concentrate metals from the environment.

Bioleaching is a process that uses bacteria to extract metals from ores or waste materials. The bacteria are able to survive in environments that are rich in metals and they can convert these metals into a form that can be easily extracted. The bacteria are usually added to a solution containing the metal ore and left to grow and multiply. As they do so, they produce acids that dissolve the metal from the ore. The solution is then treated to recover the metal. This method is particularly useful for extracting metals such as copper and gold.

Phytomining, on the other hand, uses plants to extract metals from the soil. Certain plants, known as hyperaccumulators, have the ability to absorb high concentrations of metal ions through their roots. These plants are grown in soil that contains low-grade ore or waste material. As the plants grow, they absorb the metal ions and store them in their tissues. When the plants are mature, they are harvested and burned. The ash that is left behind contains a high concentration of the metal, which can then be extracted using a variety of methods.

Both bioleaching and phytomining are considered more environmentally friendly methods of extracting metals compared to traditional mining methods. They do not require the use of harmful chemicals and they can be used to extract metals from low-grade ores or waste materials that would otherwise be considered uneconomical to mine. However, both methods are relatively slow and may not be suitable for extracting large quantities of metal.