Highly efficient separation of ethylene/ethane in microenvironment-modulated microporous polymers

Separation of ethylene (C2H4)/ethane (C2H6) is important yet extremely challenging task in petrochemical industry. Herein, three microporous polymers decorated with phenyls (PAN-P), naphthyls (PAN-NA) and anthryls (PAN-AN) were designed and synthesized in order to systematically study the correlations of the varied π-conjugation structure to the selective adsorptions of C2H6 over C2H4. The adsorption–desorption isotherms of C2H6 and C2H4 in the three polymers are completely reversible at room temperature. Moreover, it is interesting to find that at 298 K, among the three polymers, PAN-AN with the largest π-conjugation anthryl groups exhibits the highest C2H6/C2H4 dynamic selectivity of 2.70. The different adsorption/separation behaviors of C2H6/C2H4 in the three polymers are studied by means of the varied π-conjugation microenvironments as well as the porous characteristics such as specific surface areas, pore volumes and pore sizes and distribution.