Investigation of different methods of increasing membrane performance for oxygen/nitrogen separation

In recent years, air separation using membranes has received much attention as a cost-effective technology for producing relatively pure streams of nitrogen and oxygen. The results of studies show that the design and fabrication of new polymers with the desired structure for the industrialization of polymer membrane technology in the field of oxygen separation from nitrogen is considered very important. The results obtained from various research works show that polymer membranes made on the basis of aromatic polyimides and PIMs due to high selectivity, suitable mechanical, thermal and chemical properties and also benefiting from different structures due to polymer substitutions are a suitable option for separation of oxygen and nitrogen. Moreover, the membrane modification process can greatly increase the mechanical, chemical and selectivity of the membranes and be an effective way to improve the separation of oxygen from nitrogen. The results indicate that the fabrication of blended membranes has increased the selectivity and permeability of the membranes, and the creation of transverse connections in most cases has increased the selectivity of the membranes. Meanwhile, carbon molecular sieve membranes that are made by thermal decomposition of the polymeric raw material under controlled temperature and pressure conditions due to their properties such as high selectivity and permeability, stability in corrosive environments and applicability at high temperatures are suitable options for separation of oxygen and nitrogen. Also, carefully in the results obtained from various research works, it can be seen that the use of driving force and magnetic particles in the polymer simultaneously improves the permeability and selectivity of membranes. As it is predicted, this method is one of the efficient methods in improving the performance of polymer membranes in the field of oxygen and nitrogen separation.