Effects of ~(60)Co-irradiation on gas permeation properties of polyimide membranes

摘要

Radiation effects on polyimide (PI) membranes were studied with different irradiation doses by ~(60)Co. 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, H_2, CO_2, O_2, N_2 and CH_4 were 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/CH_4, H_2/CH_4, CO_2/CH_4 and H_2/N_2 of the irradiation PI membrane can be significantly improved by irradiation of ~(60)Co source. The optimum irradiation doses were 50 kGy. The highest ideal selectivity of He/CH_4, H_2/CH_4, CO_2/CH_4 and H_2/N_2 is 3635.86, 2287.57, 282.00 and 205.29, respectively. In other word, the ideal selectivity of He/CH_4, H_2/CH_4, CO_2/CH_4 and H_2/N_2 of 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.