alternative methods of extracting copper

• copper ores

  copper ores are becoming scarce
• does it mean if low grade ores are becoming scarce?


  this means we will have to extract copper from low-grade ores
• what are low grade ores?

  they only contain a small amount of the copper
• is it harder to extract the copper from low-grade ores?

  yes it is harder to extract the copper economically from these ores
• Phytoming

  plants are grown of land containing the metal compound we want

  the plant absorbs the metal compound and they concentrate it in their tissue

  the plants are then harvested and burned

  At the end, the ash contains relatively high concentration of the metal compound
• bioleaching

  uses bacteria

  bacteria are mixed with low-grade ore

  the bacteria carry out chemical reactions and produce a solution called leachate

  the leachate contains the metal we want
• extracting the copper

  can displace the copper from the compound using iron

  iron is more reactive than copper

  we usually use scrap iron which is cheap

  or we could extract the copper using electrolysis
• pros of bioleaching

  can use low-grade ores

  very economical

  cheap process

  less polluting

  reduces environmental destruction
• cons of bioleaching

  slow process compared to smelting

  some toxic chemicals are produced - harmful to the environment
• Pros of phytomining

  uses low grade ores

  uses less energy

  reduces environmental destruction#

  and land that is contaminated with low grade ores can use phytomining
• cons of phytomining

  slow process

  produces some toxic products

  the copper produced is still not pure

  it needs electrolysis - which is not energy efficient

  waste ash needs disposing off