Synthesis of Novel High Flux Thin-Film Nanocomposite Nanofiltration Membranes Containing GO–SiO2 via Interfacial Polymerization

A novel graphene oxide–silica (GO–SiO2)-embedded polyamide nanofiltration (NF) membrane was successfully constructed by the interfacial polymerization reaction between piperazine (PIP) and trimesoyl chloride on the surface of a polysulfone (PSF) microporous support. In order to improve the water flux and enhance the antifouling property, GO–SiO2 nanocomposites were dispersed in PIP solution. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and water contact angle were used to characterize the prepared membranes. The results showed that the surface properties of nanocomposite NF (TFN-NF) thin films had the tendency of more hydrophilicity and smoothness. The surface contact angle (53.7°) and surface roughness (Ra = 5.68, Ra = 7.06) of the TFN-NF membrane containing 0.01 wt % GO–SiO2 were the lowest. Furthermore, 0.01 wt % GO–SiO2/TFN showed the superior separation performance that the water flux was 43.55 L m–2 h–1 and salt rejection for NaCl, Na2SO4, MgSO4 were 40.7, 93.2, 82.4%, respectively. Also, the separation performance of the TFN-NF membrane containing 0.01 wt % GO–SiO2 was further compared with other TFN-NF membranes prepared by previous studies. Besides, after filtration of bovine serum albumin solution, the normalization of the flux of the TFN-NF membranes is 0.83, which has an improvement of 23.88% when compared with that of the bare NF membrane. The result above indicates that the modified membrane shows a better antifouling property than the TFC-NF membrane.