Carl Paul Gottfried von Linde was a German scientist, engineer, and businessman. He discovered a refrigeration cycle and invented the first industrial-scale air separation and gas liquefaction processes, which led to the first reliable and efficient compressed-ammonia refrigerator in 1876.
Carl von Linde in 1868
Von Linde in 1925
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