What is the working principle of carbon molecular sieve in nitrogen machine

Carbon molecular sieve is used to achieve the purpose of separating oxygen and nitrogen by the characteristics of screening. When the impurity gas is adsorbed by the molecular sieve, the large and medium pores only play the role of channels, transporting the adsorbed molecules to the micropores and submicropores, and the micropores and submicropores are the true volumes of adsorption. Carbon molecular sieves contain a large number of micropores, which allow molecules with small kinetic size to rapidly diffuse into the pores, while limiting the entry of large diameter molecules. Due to the difference in the relative diffusion rate of gas molecules of different sizes, the components of the gas mixture can be effectively separated. Therefore, when manufacturing carbon molecular sieve, according to the size of the molecular size, the distribution of micropores inside the carbon molecular sieve should be 0.28 ~ 0.38nm. In the micropore size range, oxygen can be quickly diffused into the pore through the micropore orifice, while nitrogen is difficult to pass through the micropore orifice, so as to achieve oxygen and nitrogen separation. Micropore size is the basis of carbon molecular sieve separation of oxygen and nitrogen, if the pore size is too large, oxygen and nitrogen molecular sieve are easy to enter the micropore, and can not play the role of separation; The aperture is too small, oxygen and nitrogen can not enter the microhole, and can not play the role of separation.