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

[Display omitted] • Microporous polymers decorated with phenyls, naphthyls and anthryls. • BET surface areas of polymers are up to 1229 m2 g−1. • Polymers possess modulated π-conjugation microenvironments. • Adsorption-desorption of C 2 H 6 and C 2 H 4 - are - reversible. • The selectivity adsorption of C 2 H 6 over C 2 H 4 is up to 2.70. Separation of ethylene (C 2 H 4)/ethane (C 2 H 6) 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 C 2 H 6 over C 2 H 4. The adsorption–desorption isotherms of C 2 H 6 and C 2 H 4 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 C 2 H 6 /C 2 H 4 dynamic selectivity of 2.70. The different adsorption/separation behaviors of C 2 H 6 /C 2 H 4 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. [ABSTRACT FROM AUTHOR]