Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA.
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Nat Mater. 2016 Aug;15(8):845-9. doi: 10.1038/nmat4621. Epub 2016 Apr 11.
The implementation of membrane-based separations in the petrochemical industry has the potential to reduce energy consumption significantly relative to conventional separation processes. Achieving this goal, however, requires the development of new membrane materials with greater selectivity, permeability and stability than available at present. Here, we report composite materials consisting of nanocrystals of metal-organic frameworks dispersed within a high-performance polyimide, which can exhibit enhanced selectivity for ethylene over ethane, greater ethylene permeability and improved membrane stability. Our results suggest that framework-polymer interactions reduce chain mobility of the polymer while simultaneously boosting membrane separation performance. The increased stability, or plasticization resistance, is expected to improve membrane utility under real process conditions for petrochemical separations and natural gas purification. Furthermore, this approach can be broadly applied to numerous polymers that encounter aggressive environments, potentially making gas separations possible that were previously inaccessible to membranes.
在石化行业中实施基于膜的分离技术具有显著降低能源消耗的潜力，与传统分离工艺相比。然而，要实现这一目标，需要开发出比现有膜材料具有更高选择性、渗透性和稳定性的新型膜材料。在这里，我们报告了由金属-有机骨架纳米晶体分散在高性能聚酰亚胺中的复合材料，其对乙烯相对于乙烷具有增强的选择性、更大的乙烯渗透性和改善的膜稳定性。我们的结果表明，骨架-聚合物相互作用降低了聚合物的链流动性，同时提高了膜分离性能。预计增加的稳定性或抗增塑性将提高石化分离和天然气净化实际工艺条件下的膜的实用性。此外，这种方法可以广泛应用于遇到苛刻环境的众多聚合物，有可能使以前无法通过膜实现的气体分离成为可能。
