In pursuit of cost-efficient adsorbent materials for capturing acetylene (C2H2) from mixtures of C2 hydrocarbons and CO2, we have designed a novel 3D framework Co7-Me·S using inexpensive isonicotinic acid (Hina) and methyl-modified isophthalic acid (H2Me-ip) as mixed linkers under hydrothermal synthesis conditions. Co7-Me·S exhibits excellent air and water stability. Its abundant carboxylate oxygen atoms and coordinated water molecules can form multiple hydrogen bonds with C2 hydrocarbon molecules. Breakthrough tests and GCMC simulations confirm that the activated Co7-Me can capture C2H2 molecules from C2H2/C2H4, C2H2/CO2, and C2H2/C2H4/CO2 mixtures and simultaneously capture C2H2 and C2H6 from a three-component C2 hydrocarbon mixture, achieving one-step purification of C2H4. Moreover, the successful acquisition of single-crystal structure data with C2H2 guest molecules further confirmed the material's high selectivity for C2H2 guest molecules.
Yang et al. (Wed,) studied this question.