The effect of graphene oxide (GO) loading (0.03, 0.06, 0.09, 0.12, and 0.30 wt%) in the aqueous phase on the performance of reverse osmosis (RO) polyimide (PI) thin film composite (TFC) membrane was investigated. TFC and thin film nanocomposite (TFN) membranes were produced through interfacial polymerization and the imide linkage was confirmed by attenuated total reflection Fourier transform infrared spectroscopy. The spongy-like structure with vertical fingers of RO PI-GO TFN membranes was explored by top-surface and cross-sectional field emission scanning electron microscope (FE-SEM). The roughness of the membranes was determined. All PI-GO TFN membranes exhibited enhanced desalination performance in comparison with PI membranes. Samples with 0.06 wt% GO performed the best with a water flux of 31.80 L/m 2 /h, salt rejection of 98.8%, and very good antibiofouling properties. This hydrophilic membrane displayed significantly enhanced chlorineresistance with water flux of 36.3 L/m 2 /h and salt rejection of 98.5%. This work provides a promising start for designing rapid water permeation PI-GO TFN membranes in water desalination.

In the present study, a simple, inexpensive, nontoxic, and environmentally friendly polyethylene glycol (PEG) polymer was used to enhance the hydrophilicity of the forward osmosis (FO) membrane using various PEG concentrations as a pore forming agent in the casting solution of polyethersulfone/polysulfone (PES/PSF) blend membranes. A nonwoven PES/PSF FO blend membrane was fabricated via the immersion precipitation phase inversion technique. The membrane dope solution was cast on polyethylene terephthalate (PET) nonwoven fabric. The results revealed that PEG is a pore forming agent and that adding PEG promotes membrane hydrophilicity. The membrane with 1 wt% PEG (PEG1) had about 27% lower contact angle than the pristine blend membrane. The PEG1 membrane has less tortuosity (which reduces from 3.4–2.73), resulting in a smaller structure parameter (S value) of 277 μm, due to the presence of open pores on the bottom surface structure, which results in diminished ICP. Using 1 M NaCl as the draw solution and distilled water as the feed solution, the PEG1 membrane exhibited higher water flux (136 L m−2 h−1) and lower reverse salt flux (1.94 g m−2 h−1). Also, the selectivity of the membrane, specific reverse salt flux, (Js/Jw) showed lower values (0.014 g/L). Actually, the PEG1 membrane has a 34.6% higher water flux than the commercial nonwoven‐cellulose triacetate (NW‐CTA) membrane. By means of varied concentrations of NaCl salt solution (0.6, 1, 1.5, and 2 M), the membrane with 1 wt% PEG showed improved FO separation performance with permeate water fluxes of 108, 136, 142, and 163 L m−2 h−1. In this work, we extend a promising gate for designing fast water flux PES/PSF/PEG FO blend membranes for water desalination.

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