Carbon Molecular Sieves is a new non-polar adsorbent in the PSA nitrogen generator, can adsorb oxygen molecules at the normal temperature, and thus available to get the abundant nitrogen, and its principle is to use screening to achieve the separation of oxygen, nitrogen purpose. The most striking characteristics of Carbon Molecular Sieve is: less impurity in N2 products, N2 purity and volume can be adjusted as needed and can be obtained by refining O2 content of less than 5PPM.