Working Principle of carbon molecular sieve

Carbon molecular sieve uses the characteristics of screening to achieve the purpose of separating oxygen and nitrogen.
When the molecular sieve adsorbs impurity gas, the large hole and the middle hole only play the role of channel, and transport the adsorbed molecules to the micropores and submicropores, and the micropores and submicropores are the real adsorption volumes.
The carbon molecular sieve contains a large number of micropores, which allow molecules with small kinetic size to rapidly spread into the pores, and at the same time limit the entry of molecules with large diameter.
Because the relative diffusion rates of gas molecules of different sizes are different, the components of gas mixture can be effectively separated. Therefore, when making carbon molecular sieve, according to the size of the molecular, The microporous distribution inside the carbon molecular sieve should be 0.28 ~ 0.38nm. Within the microporous size range, oxygen can rapidly spread into the hole through the microporous orifice, while nitrogen can hardly pass through the microporous orifice, thus achieving the separation of oxygen and nitrogen. The pore size of the carbon molecular sieve is the basis of separating oxygen and nitrogen. If the pore size is too large, both oxygen and nitrogen molecular sieve can easily enter the pore size, and can't function as separation; while the pore size is too small, neither oxygen nor nitrogen can enter the micropores, nor can it play the role of separation.