Hyaluronic acid-modified nanofiltration membrane for ultrahigh water permeance and efficient rejection of PFASs

Emerging contaminants (ECs) in water, such as per- and polyfluoroalkyl substances (PFASs), require more efficient separation technology for water treatment. Although nanofiltration (NF) has exhibited the potential to remove small organic molecules, enhancing water permeance without sacrificing the rejection of the membrane is still a big challenge. Herein, we fabricate a novel thin-film composite (TFC) membrane by introducing a hyaluronic acid (HA) interlayer. The hydrogen bonds between HA and amine monomers depress the mass transfer of piperazine, which is beneficial for constructing a thinner and denser polyamide (PA) layer. As a result, we finally obtained a novel TFC membrane with a PA layer with a more negative surface, reduced thickness, crumpled structure and higher degree of cross-linking. Moreover, the obtained TFC membrane exhibits an excellent water permeance of 29.53 L m−2 h−1 bar−1 and high rejection for Na2SO4 (94.90 %) and perfluorohexane sulfonic acid (PFHxS) (93.4 %). In light of the low cost and ease of performance, our study proposes a new, green strategy for fabricating TFC NF membranes for environmental water treatment that could feasibly be extended to industrial applications.