A new perchlorate-based hybrid ultramicroporous material with rich bare oxygen atoms for high C2H2/CO2 separation

Abstract

Adsorptive separation of acetylene (C2H2) from carbon dioxide (CO2) is of great significance in petrochemical industry, but still remains as a daunting challenge by reason of their very similar molecular sizes/shapes and physical properties. Herein, we reported a new perchlorate-based hybrid ultramicroporous material ZJU-194 that features the unique flexible-robust network decorated with rich bare oxygen atoms. By integrating the refined pore space as well as specific binding sites, the activated ZJU-194 (ZJU-194a) enables a selective two-step gate-opening adsorption toward C2H2, but blocks off the further uptake of CO2. It thus exhibits a very high C2H2/CO2 selectivity (22.4) at ambient conditions, which is superior to most reported MOF materials. Its complete separation for 50/50 C2H2/CO2 mixtures is further evidenced by the dynamic breakthrough experiments.