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Separation of the mixture of ethylene (C2H4) and ethane (C2H6) to produce polymer-grade C2H4 is of prime importance in the petrochemical industry. In this context, metal–organic frameworks (MOFs) featuring tunable pore metrics and surface chemistry, especially those with inverse C2H6/C2H4 adsorption selectivity, hold great promise in energy-effective purification of C2H4 by adsorptive separation, but often encounter the well-known trade-off between adsorption selectivity and capacity. In this work, we report two new MOFs by deploying the pore-space-partition (PSP) strategy for the purpose of reducing the pore aperture size while retaining the gas-accessible pore volume. As a result, Ni-bodc-tpt (bodc = bicyclo[2.2.2]octane-1,4-dicarboxylic acid, tpt = 2,4,6-tri(4-pyridyl)-1,3,5-triazine) by combining optimal pore size, large cage pore volume, and rich C–H binding sites exhibits concurrently high C2H6 adsorption capacity (131.65 cm3 g−1) and C2H6/C2H4 selectivity (1.8) at 298 K and 1 bar, which is superior or comparable to many benchmark C2H6-selective MOFs. A dynamic breakthrough experiment demonstrates that high-purity C2H4 (>99.9%) can be harvested in one step from a binary mixture of C2H6/C2H4 (50/50, v/v), attesting to the feasibility of this new MOF as a prospective C2H4 purification agent. [ABSTRACT FROM AUTHOR]

Purifying olefin from ternary paraffin/olefin/alkyne mixtures through a one‐step adsorption process is extremely desirable. Herein, a stable zirconium(IV) metal‐organic framework with a customized pore surface composed of nonpolar phenyl and slightly polar thiophene rings is reported to access the adsorption preference of paraffin and alkyne over olefin. Noteworthily, this material displays a superior ability to discriminate C3 hydrocarbon molecules, which is principally more challenging compared with C2 ones and rarely documented. Computational studies disclose that its featured pore shape fits well with C3 gas molecules, enabling them to get close contact with the immobilized affinity sites. Leveraging surface chemistry and pore shape engineering synergistically gives rise to excellent C3 adsorption capacities (>5 mmol g−1) and concurrently high C3H8/C3H6 (1.4) and C3H4/C3H6 (1.9) selectivities (at 298 K and 1 atm). Dynamic column breakthrough experiments demonstrate that one‐step purification of C2H4 and C3H6 can be simultaneously realized on this material. [ABSTRACT FROM AUTHOR]