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Selective separation using porous adsorbents is an energy‐efficient alternative to traditional separation techniques. Stacked porous organic molecular frameworks (POMFs) capable of noncovalent π⋅⋅⋅π interactions are emerging as a new kind of adsorbents that facilitate green separation. Here we report a robust porous molecular crystal (TAPM‐1), which is stabilized by multiple intermolecular π⋅⋅⋅π interactions. With its long‐range π‐stacking, TAPM‐1 has excellent hydrophobicity, thermostability, recyclability, and high selectivity for aromatics over the corresponding cyclic aliphatics. This enables TAPM‐1 to serve as the stationary phase in the high‐resolution gas chromatographic separation of benzene and cyclohexane or toluene and methylcyclohexane. [ABSTRACT FROM AUTHOR]

By modifying more non-polar aromatic rings in the stable ethane-selective MOF (UiO-67), more C-H∙∙∙π interactions between ethane and the main framework (UiO-67-BN) are generated, thus improving C 2 H 6 /C 2 H 4 separation while ensuring stability. [Display omitted] • With more C 2 H 6 binding sites, C 2 H 4 can be separated in one step. • UiO-67-BN has suitable pore size and a large number of non-polar surfaces, making it an excellent C 2 H 6 -selective adsorbent. • Compared with the basic material (UiO-67), the adsorption capacity, selectivity and actual separation time of the optimized material (UiO-67-BN) are greatly improved. • The material has good stability, soaking in water and various solvents for more than a week, the adsorption capacity remains unchanged. • This material can still maintain good separation effect under different humidity, temperature and flow rate, which meets the requirements of industrial production. Ethylene is an important raw material in chemical production. Reducing energy consumption by one-step separation of ethylene from C 2 H 6 /C 2 H 4 mixtures is a significant and challenging task. Designing a material with high C 2 H 6 selectivity and adsorption capacity is very demanding. Here, we report a method to improve the performance of C 2 H 6 /C 2 H 4 separation. By changing the carboxylic ligand in UiO-67, we synthesized a new material called UiO-67-BN. At room temperature, compared with the base material UiO-67, the optimized material UiO-67-BN has a significant increase in the adsorption capacity of C 2 H 6 and the selectivity of C 2 H 6 /C 2 H 4 due to its suitable pore size and numerous non-polar aromatic rings on the pore surface. Theoretical calculation results reveal that the optimized material can provide more C-H∙∙∙π interactions with C 2 H 6. The breakthrough experiments demonstrate that UiO-67-BN can efficiently capture C 2 H 6 from 50/50 and 1/99 C 2 H 6 /C 2 H 4 mixtures at various conditions and realize one-step acquisition of C 2 H 4. [ABSTRACT FROM AUTHOR]