Gas separation can refer to any of a number of techniques used to separate gases, either to give multiple products or to purify a single product.

Swing adsorption techniques

Pressure swing adsorption

Pressure swing adsorption (PSA) pressurizes and depressurizes gas around an adsorbent media to selectively adsorb certain components of a gas, allowing others to be selectively discarded.

Vacuum swing adsorption

Vacuum swing adsorption (VSA) uses the same principle as PSA but swings between

vacuum A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or " void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often di ...

pressures and

atmospheric pressure Atmospheric pressure, also known as barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1013.25 millibar ...

. The two techniques may be combined and are called "vacuum pressure swing adsorption" (VPSA) in this case.

Temperature swing adsorption

Temperature swing adsorption (TSA) uses a similar technique to other swing adsorption techniques but cycles temperature instead of pressure.

Cryogenic distillation

Cryogenic distillation is typically only used for very high volumes because of its nonlinear cost-scale relationship, which makes the process more economical at larger scales. Because of this it is typically only used for air separation.

Swing adsorption techniques

Pressure swing adsorption

Vacuum swing adsorption

Temperature swing adsorption

Cryogenic distillation

See also