1. Liquefaction:
- Air is compressed and cooled to extremely low temperatures, typically around -200°C (-328°F). This causes the air to condense into a liquid state.
2. Fractional Distillation:
- The liquefied air is then passed through a tall, cylindrical column called a fractionating column.
- This column is designed with different temperature zones, with the coldest temperature at the top and the warmest at the bottom.
- As the liquid air travels up the column, it encounters progressively cooler temperatures.
- Since different gases have different boiling points, they will vaporize at different temperatures:
- Nitrogen, with the lowest boiling point (-196°C), vaporizes first and is collected at the top of the column.
- Oxygen, with a slightly higher boiling point (-183°C), vaporizes next and is collected at a lower level.
- Argon, with an even higher boiling point (-186°C), vaporizes last and is collected near the bottom.
- Other trace gases like neon, helium, krypton, and xenon are also separated in this process.
3. Collection:
- The vaporized gases are then collected and stored as individual components.
Key Points:
* Fractional distillation relies on the difference in boiling points of the gases present in air.
* This process is used to produce large quantities of nitrogen, oxygen, and argon, which have various industrial and medical applications.
* The purity of the extracted gases can be very high, reaching up to 99.99%.
In summary, the breakdown of air into its components is a multi-step process involving liquefaction and fractional distillation based on the different boiling points of the gases present in air.
