How Can We Obtain Different Gases From Air By Fractional Distillation?

Air is a mixture of different gases (e.g. Nitrogen, oxygen and other inert gases). Some of
the gases in air have a lower boiling point and some of them have a higher boiling point.
Thus, we can separate different gases in air by using fractional distillation.

Air is first filtered to remove dust and small particles. Then, the air is compressed and
cooled down in order to liquefy it. The liquefied air is passed through sodium hydroxide
to remove carbon dioxide. And the remaining air is heated up. Different gases boil at
different temperatures. They can then be collected separately.