SIEPM reported a new kind of nanofilm for aqueous and organic nanofiltration

Nanoflms are of great interest as a kind of separation membranes for seawater desalination and wastewater treatment. Their fabrication, however, always needs a time-consuming process and shows low atom economy. Herein, we report pyrogallol/polyethyleneimine (PG/PEI) nanoflms spontaneously formed at the gas/liquid interface within ten minutes and composited on microporous substrates. Both the flm thickness and the surface charge are facilely adjusted by the reaction time and the mass ratio of PG/PEI in aqueous solution. The solution is repeatedly used to fabricate the nanoflm composite membranes and thus this method is with high atom economy of raw materials. The as-prepared nanoflm composite membranes can be directly applied in aqueous nanofltration, showing a relatively high water permeation flux (17.5 L∙m⁻²∙h⁻¹∙bar⁻¹) and salt rejection (> 94% for MgCl₂) during a long-term operation. The nanoflms are also demonstrated potentials in organic solvent nanofltration after moderate cross-linking by glutaraldehyde.

DOI：https://doi.org/10.1016/j.memsci.2018.10.052