Structural Regulation and Light Hydrocarbon Adsorption/Separation of Three Zirconium–Organic Frameworks Based on Different V‑Shaped Ligands

On
the basis of different V-shaped ligands, three zirconium–organic
frameworks (JLU-Liu45, Zr-SDBA, and Zr-OBBA) have been successfully constructed. By regulating
spatial configuration and functional groups of organic ligands, these
as-synthesized Zr-MOFs (MOF = metal–organic framework) display
distinct structures and different light hydrocarbon adsorption/separation
capabilities. JLU-Liu45, with a double-walled interpenetrated
3D primitive cubic (pcu) framework, exhibits good gas-adsorption capacity
but not prominent selective separation ability. Through regulating
sizes and torsion angles of the organic ligands, Zr-SDBA possesses a 2D square lattice (sql) network, while Zr-OBBA displays a non-interpenetrated 3D pcu framework. Furthermore, by
regulating functional groups on the ligands, Zr-SDBA shows
prominent C2H2 uptake (101.2 cm3·g–1) and the best C2H2/CH4 selectivity (230.5, 1:1) among the three Zr-MOFs, and Zr-OBBA shows a significant C3H8/CH4 selectivity
(105.6, 1:1). This work demonstrates the feasibility of structural
regulation for MOF materials in the light hydrocarbon adsorption/separation
field.