Gram-Scale Synthesis of an Ultrastable Microporous Metal-Organic Framework for Efficient Adsorptive Separation of C(2)H(2)/CO(2) and C(2)H(2)/CH(4)

A highly water and thermally stable metal-organic framework (MOF) Zn(2)(Pydc)(Ata)(2) (1, H(2)Pydc = 3,5-pyridinedicarboxylic acid; HAta = 3-amino-1,2,4-triazole) was synthesized on a large scale using inexpensive commercially available ligands for efficient separation of C(2)H(2) from CH(4) and CO(2). Compound 1 could take up 47.2 mL/g of C(2)H(2) under ambient conditions but only 33.0 mL/g of CO(2) and 19.1 mL/g of CH(4). The calculated ideal absorbed solution theory (IAST) selectivities for equimolar C(2)H(2)/CO(2) and C(2)H(2)/CH(4) were 5.1 and 21.5, respectively, comparable to those many popular MOFs. The Q(st) values for C(2)H(2), CO(2), and CH(4) at a near-zero loading in 1 were 43.1, 32.1, and 22.5 kJ mol(−1), respectively. The practical separation performance for C(2)H(2)/CO(2) mixtures was further confirmed by column breakthrough experiments.