One Co-MOF with F Active Sites for Separation of C2H2 from CO2, C2H4, and CH4

Separating acetylene (C 2 H 2 ) from other light hydrocarbons and carbon dioxide (CO 2 ) mixtures under mild conditions poses significant challenges due to the remarkably similar properties between C 2 H 2 and those gases. For the goal of C 2 H 2 separation, a F-functionalized organic linker, H 2 F-PyIP = 2-fluorine-5-(4-pyridyl)isophthalic acid, was designed, and the corresponding metal–organic framework (MOF), {[Co 2 (F-PyIP) 2 DMF]·4H 2 O} n ( 1 ), was constructed. The MOF with open channels decorated by the active sites of the F groups revealed the exceptional C 2 H 2 uptake and selectivity over CO 2, C 2 H 4, and CH 4 . The breakthrough experiments with different molar ratios of C 2 H 2 –C 2 H 4, C 2 H 2 –CO 2, and other gas mixtures further verified superior separation capacity of the MOF. In particular, the dynamic separation time intervals for gas mixtures (C 2 H 2 /CO 2 = 1:1, 1:5, 1:10, and 1:20) fell in the range 30–44 min, highlighting the potential of the MOF for tackling the challenging C 2 H 2 /CO 2 separation process.