Microporous Lanthanide Metal–Organic Framework Constructed from Lanthanide Metalloligand for Selective Separation of C₂H₂/CO₂ and C₂H₂/CH₄ at Room Temperature

A novel pillar-layer porous lanthanide metal–organic framework [Tb 3 (ODA) 3 (BPDC) 3 Na 2 ] n ·G x ( UTSA-222, G = guest molecules) was constructed from an organic ligand [1,1′-biphenyl]-4,4′-dicarboxylate (BPDC 2− ) and a lanthanide metalloligand [Tb(ODA)] + (H 2 ODA = oxydiacetic acid). The UTSA-222 contains two-dimensional intersecting channels with the Brunauer–Emmett–Teller surface area and pore volume of 703 m 2 g –1 and 0.344 cm 3 g –1, respectively, for the activated sample. It shows moderately high adsorption selectivity for C 2 H 2 /CO 2 and C 2 H 2 /CH 4 separations at 1 atm and room temperature.