Improved water flux in optimized electrospun polysulfone/nanoclay membranes

Abstract Water crisis is undoubtedly one of the main global challenges and water membranes can be used to tackle this issue. In this study, electrospun polysulfone (PSU)/nanoclay membranes were fabricated. The fabrication process was optimized to achieve desirable fibers using response surface methodology, considering nanoclay concentration, electrospinning feeding rate, and voltage as the influencing factors on the membrane properties. SEM images was used to determine the average fiber diameter and imperfection factor of the fibrous composites and their hydrophilicity was assessed based on their water contact angle (CA) values. A suitable model was proposed for each property to predict its variation with the influencing parameters. The results showed that the voltage and feed rate are directly related to the average fiber diameter and CA of the membranes. Moreover, introducing hydrophilic nanoclay to the membranes improved their wettability. The optimum properties were achieved in the membrane containing 5.63 wt% nanoclay, which was electrospun at a feed rate and voltage of 0.7 mL/h, and 16 kV, respectively. Comparing the mechanical properties and water flux performance of pure PSU membranes with the optimal sample confirmed that the presence of nanoclay improved the mechanical strength and toughness of the membranes and enhanced the attainable water flux.