Extracting Metals

• What is an ore?

  A mixture of rock/metal and other minerals/elements. They are also economically viable
• What is a low grade ore?

  A low quality ore that has a low percentage of desired metal
• Why must we extract from low grade ores?

  • High grade ores are finite
  • High demand for metal
• Two types of methods for extracting metals

  Traditional Alternative
• Examples of traditional methods of metal extraction

  Mining and smelting
• Examples of alternative methods of metals extraction

  Bioleaching and phytomining
• Steps of phytomining

  1. Copper ions in soil are absorbed by the roots of the plants
  2. Copper ions become part of the plant
  3. Plant containing the Copper is burned producing Copper oxide
  4. Ash containing Copper oxide reacts with sulphuric acid to produce Copper Sulphate
  5. Copper is extracted from Copper Sulphate through electrolysis
• What is bioleaching?

  The extraction of metals from their ore through the use of bacteria
• What is leaching?

  The movement of a liquid through an organism containing metal compounds
• Advantages of traditional methods of metal extraction

  • Quick
  • Provides jobs
  • Simpler process than alternative methods
  • Can meet metal demand quicker
  • Provides high quality metal
• Disadvantages of traditional methods of metal extraction

  • Mining destroys habitats
  • Waster from mining pollutes areas
  • Smelting produces gases such as sulpur dioxide which can cause acid rain
  • Requires a lot of energy
  • Expensive
• Advantages of alternative methods of metal extraction

  • Uses low grade ores
  • Produces less pollution than traditional methods
  • Requires less energy
  • Cheaper
• Disadvantages of alternative methods of metal extraction

  • Slower than traditional methods
  • Electrolysis requires a lot of electricity
  • Can produce toxic chemicals
• What's reduction in terms of oxygen?

  When a substances reacts and loses oxygen e.g. CuO —> Cu
• What is oxidation in terms of oxygen?

  When a substance reacts and gains oxygen e.g. Cu —> CuO
• What is reduction in terms of electrons?

  Gaining of Electrons
• What is oxidation in terms of electrons?

  Loss of electrons
• What is it called when oxidation and reduction happen in the same reaction?

  Redox