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The full separation of alkane isomers as a function of different degrees of branching remains a daunting challenge due to its stringent requirement with respect to pore dimensions of the adsorbents. In this work, we report a novel microporous coordination network built on calcium (II) and chloranilate. The compound has a flexible framework and exhibits temperature‐dependent adsorption behavior toward hexane isomers. At 30 °C, it accommodates substantial amounts of linear and monobranched hexanes but fully excludes their dibranched isomer, and at elevated temperatures such as 150 °C, it acts as a splitter for linear and branched alkanes. Its capability of efficient discrimination of hexane isomers as a function of branching is verified by experimental breakthrough measurements. Ab initio calculations have uncovered the underlying selective size‐exclusion separation mechanism. [ABSTRACT FROM AUTHOR]

The full separation of alkane isomers as a function of different degrees of branching remains a daunting challenge due to its stringent requirement with respect to pore dimensions of the adsorbents. In this work, we report a novel microporous coordination network built on calcium (II) and chloranilate. The compound has a flexible framework and exhibits temperature‐dependent adsorption behavior toward hexane isomers. At 30 °C, it accommodates substantial amounts of linear and monobranched hexanes but fully excludes their dibranched isomer, and at elevated temperatures such as 150 °C, it acts as a splitter for linear and branched alkanes. Its capability of efficient discrimination of hexane isomers as a function of branching is verified by experimental breakthrough measurements. Ab initio calculations have uncovered the underlying selective size‐exclusion separation mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn) showed efficient C 3 H 6 /C 3 H 8 separation. • The separation mechanism was based on the thermodynamic-kinetic synergetic effect. • Ni(AIP)(BPY) 0.5 had the highest C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient adsorption separation of propylene (C 3 H 6) and propane (C 3 H 8) can largely lower the energy consumption compared to the current energy-intensive cryogenic distillation. Herein, we report an isoreticular family of pillar-layer metal–organic frameworks (MOFs), M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn), for efficient C 3 H 6 /C 3 H 8 separation by simultaneously exploiting thermodynamic and kinetic effects, circumventing disadvantages of each separation mechanism. The three MOFs feature an open metal site for each metal node and uniform but narrow one-dimensional (1D) channels, offering strong binding sites toward C 3 H 6 via π-complexations while obstructing the diffusion of bulkier C 3 H 8. The Ni-MOF shows the best separation performance based on the highest thermodynamic and kinetic C 3 H 6 /C 3 H 8 selectivities, further verified by computational simulations. Ni(AIP)(BPY) 0.5 has a moderate C 3 H 6 uptake of 1.94 mmol/g but a remarkably high C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient C 3 H 6 /C 3 H 8 separation, good recyclability, moisture and water stability of Ni(AIP)(BPY) 0.5 are confirmed. [ABSTRACT FROM AUTHOR]

Developing new techniques and materials for ethylene (C 2 H 4) and ethane (C 2 H 6) separation is an industrially significant but challenging task. Here we report two isoreticular pillar-layer metal-organic frameworks, Co(aip)(bpy) 0.5 and Co(aip)(pyz) 0.5 , for the separation of C 2 H 4 /C 2 H 6. The pore apertures of the pillar-layer metal-organic frameworks are rationally controlled by changing the length of the pillar ligands. Significantly, Co(aip)(pyz) 0.5 with a shorter pillar ligand shows reduced pore size and molecular sieving separation of C 2 H 4 from C 2 H 6. Co(aip)(pyz) 0.5 has a moderate C 2 H 4 capacity of 1.78 mmol/g but ultrahigh C 2 H 4 /C 2 H 6 selectivity exceeding 2000 at ambient conditions. The molecular simulation revealed that large torsion angle between the organic linker plane and Co–O bond leads to the high energy barrier for C 2 H 6 to enter into the pore, which results in the molecular sieving separation of C 2 H 4 /C 2 H 6. Dynamic breakthrough experiments confirmed the high selectivity of Co(aip)(pyz) 0.5 for C 2 H 4. And high-purity C 2 H 4 (>97%) with a C 2 H 4 productivity of 19.1 l/kg can be obtained through the desorption process. Meanwhile, the excellent reusability and moisture stability endow it great potential for applications in adsorptive separation. [Display omitted] • The pore apertures of the pillar-layer MOFs are rationally controlled. • Co(aip)(pyz) 0.5 showed the molecular sieving separation of C 2 H 4 /C 2 H 6. [ABSTRACT FROM AUTHOR]