Regulate interfacial polymerization in cyclodextrin-based metal-organic frameworks/graphene oxide-modified PVDF membranes for desalination
In recent years, composite nanofiltration membranes have emerged as a popular desalination technology because of their unique structures. However, the “trade-off” effect posed a significant limitation on the advancement of nanofiltration membrane applications. In this study, cyclodextrin-based metal–organic frameworks (CD-MOF/GO) were uniformly embedded into a substrate membrane to modulate the motion of piperazine molecules during the interfacial polymerization process. This method has the potential to reconfigure the spatial structure of the polyamide active layer and bolster the performance of composite nanofiltration membranes. First, the CD-MOF/GO within the pores could slow down the diffusion rate of piperazine to facilitate the formation of an ultrathin active layer, which diminished the resistance to the mass transfer of water molecules to improve the membrane performance. Simultaneously, the unique nanocavity structure of CD-MOF/GO could provide more unobstructed pathways for water molecules to permeate through the membrane. The results demonstrated that the flux of the composite nanofiltration membrane modified with MOF could reach up to 19.44 L·m −2 ·h −1 ·bar −1 , which is approximately four times higher than that of the unmodified membrane, while maintaining a high Na 2 SO 4 rejection rate of 95.52 %. The CD-MOF/GO-modified nanofiltration membrane effectively overcomes flux limitations, showing potential in mitigating the “trade-off” effect and offering a promising approach for achieving efficient seawater desalination.
危险品化学品经营许可证（带存储）