Adsorption rate and principle of oxygen and nitrogen on carbon molecular sieve



In the complete equipment of the nitrogen machine, what is the adsorption rate and principle of carbon molecular sieve for oxygen and nitrogen?

Oxygen and nitrogen have different diffusion rates on the surface of the molecular sieve. The gas molecule with smaller diameter (O2) has a faster diffusion rate and more enters the micropores of the carbon molecular sieve, while the gas molecule with larger diameter (N2) has a slower diffusion rate and less enters the micropores of the carbon molecular sieve. This selective adsorption difference between nitrogen and oxygen by carbon molecular sieve leads to oxygen enrichment in adsorption phase and nitrogen enrichment in gas phase in a short time, so as to achieve oxygen and nitrogen separation, and gas phase enrichment nitrogen is obtained under PSA conditions.

After a period of time, the adsorption of oxygen by the molecular sieve reaches a balance. According to the characteristics of the adsorption amount of adsorbed gas by the carbon molecular sieve under different pressures, the pressure is reduced to remove the adsorption of oxygen by the carbon molecular sieve, which is a process of regeneration. According to the different regeneration pressure, it can be divided into vacuum regeneration and atmospheric regeneration. Atmospheric regeneration is conducive to the thorough regeneration of molecular sieve and easy to obtain high purity gas.

Pressure swing adsorption nitrogen machine (PSA nitrogen machine for short) is a nitrogen generating equipment designed and manufactured according to pressure swing adsorption technology. Two adsorption towers are usually used in parallel, and the automatic control system strictly controls the timing according to a specific programmable program, alternately performs pressure adsorption and decompression regeneration, completes nitrogen and oxygen separation, and obtains the required high purity nitrogen.