Aromatic Polyamides for Gas Separation Application

There are current environmentally friendly processes for separation and purification methods by gas separation membrane technologies that are cost-effective for selective applications. Aromatic PAs 

Ding and Bikson described prepared the dens membranes from aromatic PAs containing 2,3-dihydro-l,l,3-trimethyl-lH-indene moieties in the main chain and investigated their gas transport properties [81]. The membranes showed high gas permeability coefficients and gas separation factors. The nonsymmetric and non-planar diacid residue results in desirable gas transport properties. However, PAs containing 1,1,1,3,3,3-hexa luoro-2,2-diphenylpro-pane exhibited higher gas permeability coefficients and modestly lower gas separation factors. 

Recently, Ekiner and Simmons reported on membranes for the production of oxygen-enriched air, nitrogen-enriched air, for the separation of carbon dioxide from hydrocarbons, and the separation of hydrogen from various petrochemical and oil refining streams [82]. The membranes are made with blends of PAs, Pis and PI-PAs. They show high strength, chemical resistance, and are suitable for high pressure and temperature applications. 

---