Zhang Xin, Chen Qiancheng, Bai Xuefeng, Zhao Yan-Long, Li Jian-Rong
Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering, College of Materials Science & Engineering, Beijing University of Technology, Beijing, 100124, China.
Angew Chem Int Ed Engl. 2024 Nov 4;63(45):e202411744. doi: 10.1002/anie.202411744. Epub 2024 Sep 10.
Adsorptive CH/CH separation using metal-organic frameworks (MOFs) has emerged as a promising technology for the removal of CH (acetylene) impurity (1 %) from CH (ethylene). The practical application of these materials involves the optimization of separation performance as well as development of scalable and green production protocols. Herein, we report the efficient CH/CH separation in a MOF, Cu(OH)INA (INA: isonicotinate) which achieves a record CH packing density of 351 mg cm at 0.01 bar through high affinity towards CH. DFT (density functional theory) calculations reveal the synergistic binding mechanism through pore confinement and the oxygen sites in pore wall. The weakly basic nature of binding sites leads to a relatively low heat of adsorption (Q) of approximately 36 kJ/mol, which is beneficial for material regeneration and thermal management. Furthermore, a scalable and environmentally friendly synthesis protocol with a high space-time yield of 544 kg m day has been developed without using any modulating agents. This material also demonstrates enduring separation performance for multiple cycles, maintaining its efficacy after exposure to water or air for three months.
使用金属有机框架（MOF）进行吸附性C₂H₂/C₂H₄分离，已成为从C₂H₄中去除1% C₂H₂（乙炔）杂质的一项很有前景的技术。这些材料的实际应用涉及分离性能的优化以及可扩展和绿色生产方案的开发。在此，我们报道了一种MOF，即Cu(OH)INA（INA：异烟酸酯）中的高效C₂H₂/C₂H₄分离，它通过对C₂H₂的高亲和力，在0.01 bar下实现了创纪录的351 mg cm⁻³的C₂H₂填充密度。密度泛函理论（DFT）计算揭示了通过孔道限制和孔壁中的氧位点的协同结合机制。结合位点的弱碱性导致吸附热（Q）相对较低，约为36 kJ/mol，这有利于材料再生和热管理。此外，已开发出一种可扩展且环境友好的合成方案，时空产率高达544 kg m⁻² day⁻¹，且未使用任何调节剂。这种材料还展示了多个循环的持久分离性能，在暴露于水或空气中三个月后仍保持其效能。
