Extracting metals

• Phytomining:

  1. plants are grown in soil that contains low grade ore
  2. the plants absorb metal ions through their roots and concentrate these ions in their cells
  3. the plants are harvested and burnt
  4. the ash left behind contains metal compounds
• Bioleaching:

  Certain bacteria can break down low-grade ores to produce an acidic solution containing copper ions.

  The solution is called a Leachate
• phytomining:

  Pros:

  • reduces the need to obtain new ore by mining
  • conserves limited supplies of high-grade ores
  • reduces the amount of rock waste that must be disposed of after traditional mining

  Cons:

  • very slow
• Bioleaching

  Pros:

  • does not need high temperatures

  Cons:

  • produces toxic substances, including sulfuric acid, which damage the environment