Yu Chenyi, Wang Keke, Zhao Beiyu, Lin Yiming, Zhou Changjiang, Huo Xianliang, Xie Bo, Wen Hui-Min, She Yuanbin, Hu Jun
College of Chemical Engineering, Zhejiang University of Technology, Zhejiang 310014, PR China.
Inorg Chem. 2025 Apr 21;64(15):7746-7752. doi: 10.1021/acs.inorgchem.5c00745. Epub 2025 Apr 7.
The separation of ethane (CH) from ethylene (CH) is critical for obtaining polymer-grade CH. Adsorptive separation with CH-selective MOFs offers a viable alternative to energy-intensive cryogenic distillation, enabling the direct production of high-purity CH. In this study, we developed an ultrastable ethane-selective metal-organic framework, UiO-67-(CH), which demonstrates enhanced CH adsorption (4.10 mmol g at 1 bar and 298 K), higher CH/CH selectivity of 1.70, and an increased CH/CH adsorption ratio of 1.53 compared to unmodified UiO-67. GCMC simulations demonstrate that CH forms more C-H···π interactions with the surrounding benzene rings and more C-H···C interactions with methyl groups compared to CH, highlighting the synergistic effects of supramolecular interactions. Furthermore, the hydrophobic pore environment also minimizes water interference, with exceptionally low water uptake (0.019 g g at 60% RH), ensuring robust separation capacity under high humid conditions. The introduction of methyl groups not only significantly enhances CH adsorption performance and CH/CH separation selectivity but also improves material's hydrophobicity.
从乙烯（CH₂=CH₂）中分离乙烷（CH₃CH₃）对于获得聚合物级CH₂=CH₂至关重要。使用对CH₃CH₃具有选择性的金属有机框架（MOF）进行吸附分离为能源密集型低温蒸馏提供了一种可行的替代方案，能够直接生产高纯度的CH₂=CH₂。在本研究中，我们开发了一种超稳定的乙烷选择性金属有机框架UiO-67-(CH₃)，与未改性的UiO-67相比，它表现出增强的CH₃CH₃吸附性能（在1 bar和298 K下为4.10 mmol g⁻¹）、更高的CH₃CH₃/CH₂=CH₂选择性1.70以及增加的CH₃CH₃/CH₂=CH₂吸附比1.53。巨正则蒙特卡罗（GCMC）模拟表明，与CH₂=CH₂相比，CH₃CH₃与周围苯环形成更多的C-H···π相互作用，与甲基形成更多的C-H···C相互作用，突出了超分子相互作用的协同效应。此外，疏水的孔环境还将水的干扰降至最低，水吸附量极低（在60%相对湿度下为0.019 g g⁻¹），确保在高湿条件下具有强大的分离能力。甲基的引入不仅显著提高了CH₃CH₃的吸附性能和CH₃CH₃/CH₂=CH₂的分离选择性，还提高了材料的疏水性。
