Polyamide nanofilm composite membranes (NCMs) supported by chitosan coated electrospun nanofibrous membranes: Preparation and separation performance research Original Research Article

Polyamide nanofilm composite membranes (NCMs) were prepared by interfacial polymerization on the surface of chitosan coated electrospun polyacrylonitrile (PAN) nanofibrous membranes. The NCMs displayed unique surface ridge-and-valley morphologies as that of commercial polyamide thin film composite (PA-TFC) membranes, indicating their potential applications on water desalination. The factors influencing the NCMs structures, including sodium lauryl sulfate (SLS) concentrations, glutaraldehyde and chitosan concentrations, were investigated. The obtained NCMs were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), and contact angle measurements. The separation properties of NCMs were investigated by a lab-scale cross-flow apparatus. With the optimized condition, the obtained membrane exhibited a permeation of as high as 52.8 L/m2·h, which is even higher than the commercial PA-TFC membranes with a NaCl rejection of 54.1% at the pressure of 0.9 MPa with the initial NaCl concentration of 1000 mg/L. The correlation between the structures and separation properties of the NCMs were also studied. The NCMs can be potential alternatives for desalination membranes.