Dear Researchers,

How can we classified membranes used for gas separation (like H2, O2, N2, CO2, CH4, C2H6 etc) as defected and defected-free membrane? can we classified membranes as defected if O2/N2 (having kinetic diameter of 3.46 an 3.64 Angstrom) separation factor/ selectivity is less than a certain value like 0.6, 0.8, 1, 1.2, 1.4, 1.6...2 etc ? 

Regards,

Muhammad Usmand