| N₂ |
~78.08% |
cryogenic distillation , pressure swing adsorption, membrane separation |
up to 99.999% |
high |
chemical processes, electronics, food packaging, metal processing |
| O₂ |
~20.95% |
cryogenic distillation , pressure swing adsorption, membrane separation |
up to 99.7% |
high |
medical use, industrial processes, water treatment |
| $AR |
~0.93% |
cryogenic distillation |
up to 99.999% |
high |
welding, lighting, semiconductor manufacturing |
| CO₂ |
~0.041% |
chemical scrubbing, cryogenic distillation |
varies, high concentrations possible |
varies |
beverage carbonation, greenhouse cultivation, industrial processes |
| NE |
less than 0.002% |
cryogenic distillation |
up to 99.999% |
moderate to high |
lighting, lasers, refrigerants |
| HE |
about 0.0005% |
cryogenic distillation |
up to 99.999% |
moderate to high |
balloons, medical imaging, scientific research |
| CH₄ |
about 0.0002% |
adsorption techniques, membrane separation |
varies, high for specific setups |
moderate to high |
fuel, chemical feedstock, energy production |
| KR |
about 0.0001% |
cryogenic distillation |
up to 99.999% |
moderate to high |
lighting, insulation in double-glazed windows |
| H₂ |
about 0.00005% |
pressure swing adsorption, membrane separation, electrolysis |
up to 99.999% |
moderate to high |
fuel cells, refining, chemical synthesis |