عنوان مقاله [English]
The application of hydrophilic nanoparticles to modify the surface of the membrane is one of the suitable approaches to improve the properties of thin-film composite membranes, particularly for the removal of heavy metals from aqueous environments. In this research, a thin-film polyamide nanofiltration membrane with porous polysulfone substrate was prepared by TMC and PIP interfacial polymerization technique. To modify the surface of TFC membranes and produce new TFN membranes by a nanoparticle coating method, graphene oxide nanoparticles modified with 3-aminopropyltriethoxysilane were dispersed in EDC solution as an activator of functional groups, and then were layered by coating the surface of the polyamide membrane. Physicochemical features using scanning electron microscopy, Fourier Transform Infrared, water contact angle, and hydrophilicity to assess structure, morphology as well as tests of water flux and rejection rate were evaluated to estimate the performance and efficiency of the synthesized membranes in the filtration system. The findings indicated that increasing the concentration of nanoparticles improves the hydrophilicity nanocomposite membranes compared to neat TFC membranes. Functional results and membrane filtration indicated that the amount of neat water permeability of the fabricated membranes increases with increasing concentration of graphene oxide nanoparticles from about 42 L/m2.h for TFC membrane to 95 L/m2.h for the membrane containing 0.1 weight percent of graphene oxide. This trend shows the positive effect of nanoparticles on membrane water permeability. Furthermore, the rejection of cobalt heavy metal with increasing pH from 3 to 8 for all membrane samples has an upward trend, so that TFN3 membrane has the highest rate of rejection (98%) of heavy metal compared to other membranes while the amount of flux with changing pH and increasing the concentration of nanoparticles, has a decreasing trend. So, this technique can be applied as a new and effective method for the removal of heavy metals.