An air separation plant separates atmospheric air into its primary components, typically nitrogen and oxygen, and sometimes also argon and other rare inert gases.
Distillation column in a cryogenic air separation plant
A nitrogen generator
Bottle of 4Å molecular sieves
Membrane nitrogen generator
Argon is a chemical element; it has symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most abundant gas in Earth's atmosphere, at 0.934%. It is more than twice as abundant as water vapor, 23 times as abundant as carbon dioxide, and more than 500 times as abundant as neon. Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust.
Argon
A small piece of rapidly melting solid argon
Captioned "Argon", caricature of Lord Rayleigh in Vanity Fair, 1899
Cylinders containing argon gas for use in extinguishing fire without damaging server equipment