Highly Hydrophobic Electrospun Reduced Graphene Oxide/Poly(vinylidene fluoride-co-hexafluoropropylene) Membranes for Use in Membrane Distillation

Membrane distillation has seen a growing amount of industrial interest due to its low operating pressure, minimal temperature requirements, and high salt rejection. This body of work involves the fabrication of a microporous nanocomposite membrane with enhanced hydrophobicity for use in a direct contact membrane distillation (DCMD) process. Reduced graphene oxide/poly(vinylidene fluoride-co-hexafluoropropylene) (rGO/PVDF-HFP) flatsheet membranes were prepared via a facile electrospinning technique. These fabricated membranes were characterized using techniques including SEM, XPS, AFM, a TGA test, liquid entry pressure (LEP), and the measurement of contact angle in order to investigate the effect that incorporating rGO has on membrane morphology and performance. Results demonstrated that a maximum water contact angle of 139 degrees was achieved with an increased liquid entry pressure (LEP) of up to 103.42 kPa. Antifouling and antiwetting performance of fabricated membranes were investigated through a direct contact membrane distillation (DCMD) process, using 60 g/L sodium chloride as a feed solution for 2520 min (42 h). The rGO incorporated membranes exhibited excellent stability and durability with a salt rejection of over 99.97% and an average flux of 20.37 kg/m(2) h, indicating the promise of reduced graphene oxide based hydrophobic membranes for applications in desalination, wastewater disposal, and food processing.