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Effective fractionation of dyes and salts (NaCl) potentially paves a new path to sustainable treatment of textile wastewater. Herein, a loose nanofiltration (NF) membrane was innovatively used as the anion conductive membrane in electrodialysis (ED) for dye and salt separation. The NF membrane with a molecular weight cut-off of 678 Da showed a sufficient retention for reactive dyes with small molecular weights (<627 Da) predominantly based on synergistic effect of steric repulsion and Donnan repulsion. Simultaneously, the NF membrane had a considerably fast transport for anions (i.e., Cl−), as its loose surface structure created extra nano-channels for ion transfer. The anion conductive loose NF membrane based ED process yielded excellent separation performance in a one-step dye/NaCl fractionation. Specifically, a 98.9% desalination efficiency was obtained by the loose NF-based ED process along with 99.4% dye recovery. Additionally, an extremely low fouling propensity was observed during a 5-cycle ED operation, as the negative surface charge of the loose NF membrane served as an intrinsic barrier to prevent the dye species from entering the membrane pores through electrostatic repulsion. This study demonstrated a desirable potential of loose NF membranes as anion conductive membranes in ED for resource recovery from highly-saline wastewater. Image 1 1. Loose nanofiltration (NF)-based electrodialysis (ED) was used for dye/salt separation 2. Loose NF membrane shows an excellent ion transport as anion conductive membrane 3. Loose NF-based ED yields 98.9% desalination efficiency and 99.4% dye recovery 4. Low fouling propensity is observed for loose NF membrane as anion conductive membrane [ABSTRACT FROM AUTHOR]

• Superhydrophobic PVDF membrane was fabricated by spray-coating of fluorinated SiO 2 NPs. • Superhydrophobic PVDF membrane had a water contact angle of 171.8 ± 1.1° and sliding angle of 1.69 ± 0.13°. • The modified PVDF membrane maintained stable superhydrophobicity under harsh conditions. • The prepared membrane has consistent separation efficiencies up to 99.88 ± 0.03% in water-in-oil emulsions over 40 cycles. • Scale-up fabrication of superhydrophobic PVDF membrane was successfully performed. Hydrophobic anti-wetting membranes have many applications, such as oily wastewater treatment via oil/water separation, desalination via membrane distillation, and carbon capture via gas-liquid membrane contactors. Herein, we used a simple and scalable method to fabricate robust superhydrophobic polyvinylidene fluoride (PVDF) based membranes by one-step spray-coating of fluorinated SiO 2 nanoparticles. The prepared PVDF membrane was systematically characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and contact angle measurements. The modified PVDF membrane had excellent superhydrophobicity with an extremely high water contact angle up to 171.8 ± 1.1° and a low sliding angle of 1.69 ± 0.13°, due to the fluorinated close-packed hydrophobic SiO 2 nanoparticles on the surface. The modified PVDF membrane maintained its relatively stable superhydrophobicity under various harsh conditions, i.e., exposure in hot water, NaOH and HCl, ultrasonication and high-speed flushing, indicating the superior robustness and stability. The prepared membrane also exhibited consistent separation efficiencies up to 99.88 ± 0.03% in water-in-oil emulsions, and superior recyclability and durability over 40 cycles. In addition, spray-coating showed its great promise in engineering various superhydrophobic surfaces on different substrates and excellent scalability in fabricating large-size membranes. This study demonstrates a facilely scalable spray-coating method for engineering robust superhydrophobic surfaces and membranes that can be potentially used for various gas, vapor and water/oil separations. [ABSTRACT FROM AUTHOR]