1, purify the air, in the air separation equipment, the air first needs to go through filtration and other pretreatment to remove the dust, mechanical impurities and other large particles, but the air may also contain some trace harmful gases and impurities. Molecular sieve has a highly developed pore structure and huge specific surface area, which can adsorb trace impurities in the air.
2, the depth of dehydration, the air contains a certain amount of water vapor, even after preliminary cooling and drying treatment, may still not be able to meet the strict requirements of the moisture content of the air separation equipment. Molecular sieve has a strong affinity for water molecules, can selectively adsorb water vapor in the air, the moisture content in the air to a very low level, generally can be controlled in the moisture content of one millionth (ppm) level.
3, to remove carbon dioxide, carbon dioxide at low temperatures will solidify into dry ice, blocking equipment and piping, affecting the normal operation of the air separation process. Molecular sieve has good adsorption performance for carbon dioxide, and can reduce the carbon dioxide content in the air to a very low level at room temperature.
4, remove some hydrocarbons, in addition to unsaturated hydrocarbons, the air may also contain methane, ethane and other saturated hydrocarbons. Although these saturated hydrocarbons at room temperature activity is relatively low, but in the low-temperature and high-pressure air separation environment, they may also gradually accumulate, posing a threat to equipment safety. Molecular sieves also have a certain adsorption capacity for some hydrocarbons, which can further reduce the content of hydrocarbons in the air.