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1. Filter the air/electrostatic precipitation/purify the air
2. Pass air through sodium hydroxide (NaOH) or potassium hydroxide (KOH) to remove carbon (IV) oxide (CO2)
3. Cool to -25o to remove water vapour
4. Cool the remaining gases to form a liquid air
5. Perform fractional distillation of liquid air at -200oC
6. Nitrogen is collected at -196oC
johnmulu answered the question on February 6, 2017 at 05:51
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