How Do You Separate the Gases in Air?

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The gases in air can be separated from one another through a process known as the fractional distillation of liquid air. This is a process that converts air into a liquid form and then allows it to be portioned out into layers and separated from one another. Because pure oxygen and nitrogen have a number of applications, this is a useful technique.

Fractional distillation is a process that can separate gases from one another if they can be converted into a liquid form. To perform this separation on air, it must be cooled to a very low temperature so that it liquefies. Once this is done, the air can be passed into the bottom of a fractionating column. This column slowly raises the temperature until the oxygen and nitrogen in the air are separate from one another. From there, two tubes separately pipe off the gases.

This process can be repeated on the oxygen because in many cases, there are still trace amounts of argon found in the oxygen. Pure nitrogen, oxygen and argon can be removed from the air by the end of the final fractional distillation. The nitrogen is used in a number of different settings, especially the food and grocery industries.