Preparation and characterization of novel thin film composite forward osmosis membrane with halloysite nanotube interlayer

In this study, the electrospun polyacrylonitrile (ePAN) fiber mats were used as support layer and natural mineralhalloysite nanotubes (HNTs) was used to construct the interlayer. Polydopamine modification was utilized to enhance the hydrophilicity of ePAN substrates and dispersibility of HNTs. The mHNTs interlayer effectively minified the surface pore size of substrates providing a better interface for interfacial polymerization forming an integrated and thin PA selective layers. Compared to the unmodified membranes, the water flux of the optimized membrane with mHNTs interlayer about 61.60% and 79.70% higher and the reverse salt flux of which was 38.95% and 45.08% lower in AL-FS mode and AL-DS mode respectively. These results suggested that introducing halloysite nanotube interlayer is an effective, and low-cost way to fabricate high-performance FO membrane.

Automated summary

In this study, high-performance FO membranes were successfully fabricated by introducing a polydopamine-modified mineral nanotube interlayer. The interlayer effectively reduced the surface pore size of the membrane, improving the interface for interfacial polymerization and enhancing the water flux while reducing the reverse salt flux.