(a) Explain how, nitrogen, oxygen, and argon gases are separated from air.(b) Draw a flow diagram of the processes involved in obtaining gases like nitrogen, oxygen, and argon from the air.

(a) Nitrogen, oxygen, and argon are separated from the air by fractional distillation. The following steps must be followed to separate these gases from the air:
  1. Air is first filtered to remove the dust particles, spores etc. Subsequently, water vapours and carbon dioxide are removed.
  2. Air is subjected to high pressure and then cooled. This air is then allowed to expand in a chamber which causes further cooling of the air.
  3. This process is repeated to cool the air further. The air becomes so cold that it turns into a liquid.
  4. Liquid air is then fed into a fractionating column from its bottom end and is cooled slowly.
  5. Liquid nitrogen boils off first to nitrogen gas as the boiling point of nitrogen is lowest at -196°C.
  6. Liquid argon boils off at a boiling point of -186°C.
  7. Liquid oxygen boils off last as it has the highest boiling point among all three (around -183°C).


Simply Easy Learning

Updated on: 10-Oct-2022


Kickstart Your Career

Get certified by completing the course

Get Started