Effects of 60Co-Irradiation on Gas Permeation Properties of Polyimide Membranes

Abstract

Radiation effects on polyimide (PI) membranes were studied with different irradiation doses by60Co. The PI membrane were synthesized from 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (Bis-AP-AF) with 3,3',4,4'-Benzophenone tetracarboxylic dianhydride (BTDA). The single gas permeability of He, H2, CO2, O2, N2and CH4were measured and compared in order to determine the effect of the the irradiation doses on the gas separation properties. The results showed that the ideal selectivity of He/CH4, H2/CH4, CO2/CH4and H2/N2of the irradiation PI membrane can be significantly improved by irradiation of60Co source. The optimum irradiation doses were 50 kGy. The highest ideal selectivity of He/CH4, H2/CH4, CO2/CH4and H2/N2is 3635.86, 2287.57, 282.00 and 205.29, respectively. In other word, the ideal selectivity of He/CH4, H2/CH4, CO2/CH4and H2/N2of the irradiation PI membrane with 50 kGy irradiation doses is 2.27, 2.11, 1.89 and 1.08 times higher than that of the PI membranes without irradiation.