The core technology of the nKRT series research molecular sieve oxygen production system, which uses 10 cubic meters of oxygen for county-level hospitals, is to separate oxygen and nitrogen in the air through molecular sieve pressure swing adsorption (PSA) to obtain oxygen. $r $n zeolite has the characteristics of high pressure adsorption and low pressure desorption of nitrogen gas. Therefore, by alternating high and low pressure program control of the adsorption tower containing zeolite molecular sieves, oxygen can be directly produced from the air. This process is a physical process, and molecular sieves are not consumed.