Both of the key technologies that are responsible of separation of N2 from compressed air were both developed in the 1960’s. The two main processes are Pressure Swing adsorption (PSA), and Hollow Fiber Membrane Technology (HFM).
Pressure Swing adsorption (PSA) which is the process of gases being adsorbed into surface areas made up of materials like activated carbon, or zeolite under high pressures, and then are desorbed when pressure is reduced. This technology was first developed, and used by Union Carbide to purify hydrogen for the Aerospace industry. This technology ultimately moved into different factions based on the process of the technology in relation to the chemical makeup of materials and their interaction with specific media. Examples would be separation of CO2 from Biogas, Oxygen and Nitrogen from Air, and impurities from hydrogen.
Hollow Fiber Membrane technology (HFM) is the process of media passing through artificial membrane material made from a polymer, which contains a permeable barrier. This technology first found its purpose for Reverse Osmosis, and water filtration. It is also used for desalination of water, as well as used for cell culture, and tissue engineering. Based on the polymer makeup of the membrane cartridge a membrane can be used to strip specific gases such as Carbon Dioxide from natural gas, and O2 from Air. Based on pressure, and temperature of the treated air, O2 the smaller of the two molecules permeates within the fiber allowing the N2 molecules to pass through.
To be continued.....