丙烯/丙烷分离的ZIF-8膜研究进展

同碳数烯烃/烷烃的分离是目前石油化工行业中最耗能的过程之一，开发新型的、低能耗的丙烯/丙烷分离过程被认为是改变世界的七项化工分离技术之一。气体膜分离技术因其高效、节能和环境友好等优点被认为是一种可取代传统低温精馏分离丙烯/丙烷混合气体的新型技术。金属有机骨架材料ZIF-8的有效孔径介于丙烯和丙烷的分子动力学直径之间，可对丙烯/丙烷实现高效分离，是目前分离丙烯/丙烷性能最好的膜材料。本文系统总结了ZIF-8膜的制备方法及用于丙烯/丙烷高效分离的发展历程；探讨了ZIF-8膜微结构的调控，尤其是膜缺陷的修复及ZIF-8骨架柔性的控制；总结了ZIF-8膜在分离丙烯/丙烷时，过程参数对于分离性能的影响规律；并提出ZIF-8膜规模化制备及潜在工业分离丙烯/丙烷研究中存在的问题和未来发展方向。

Recent progress of ZIF-8 membrane for propylene/propane separation

Separation of olefins/paraffins with the same carbon number is currently one of the most energy-consuming processes in the petrochemical industry. The development of new, low-energy propylene/propane separation processes is considered to be one of the seven chemical separation technologies that can change the world. Gas separation membrane technology is considered to be an alternative technology for replacing conventional cryogenic distillation to separate propylene/propane mixture due to its high efficiency, energy-saving and environmental-friendliness. The effective pore diameter of the metal-organic framework material ZIF-8 is just between the molecular dynamic diameters of propylene and propane, which can achieve efficient separation of propylene/propane. Among various membrane materials, ZIF-8 exhibits the best separation performance for propylene/propane mixture. This review systematically summarized the both preparation method and development process of ZIF-8 membrane for propylene/propane separation. The regulation of ZIF-8 membrane microstructure, especially the repair of membrane defects and the control of ZIF-8 framework flexibility, was discussed. The influence of the process parameters on the propylene/propane separation performance of ZIF-8 membrane was also discussed. The problems and future development of ZIF-8 membrane in large-scale preparation and potential industrial separation of propylene/propane were proposed.