Polyethersulfone nanofiltration membrane embedded by magnetically modified MOF (MOF@Fe3O4): fabrication, characterization and performance in dye removal from water using factorial design experiments

In this study, the nanofiltration (NF) membrane filled with magnetically modified metal organic framework nanoparticle (MOF@Fe3O4) was fabricated by employing the conventional phase inversion method. The synthesized nanoparticle was identified by FTIR, XRD, TEM and BET techniques. The MOF@Fe3O4 incorporated and bare NF membranes were characterized by analysis of EDX, EDS, SEM, TGA, water contact angle measurement, porosity and mean pore size. The performance of the fabricated membranes was evaluated in terms of permeability and antifouling activities. Further, in order to examine dye rejection of the chosen membrane, acid orange 7 was employed as a model pollutant. The effect of different variables, i.e., pH and temperature at three different levels, on the membrane function while filtering dye solution was studied by employing central composite design (CCD) of the response surface methodology (RSM) using Design Expert Software. Thermal stability of the modified membranes was enhanced after the introduction of MOF@Fe3O4. According to experimental findings, 0.5 wt.% incorporated NF membrane revealed the best performance. The highest dye removal efficiency was obtained at a pH and temperature of 3 and 25 °C, respectively.