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Designing efficient membranes for desalination to help reduce the water shortage crisis has been the subject of various studies. In this study, first, CuAl LDH nanosheets were prepared and the surface of some thin-film composite (TFC) membranes was modified by them. Afterward, the novel heterostructure nanocomposite consisting of CuAl LDH and WS2 nanosheets was synthesized by hydrothermal method, and a new kind of thin-film nanocomposite (TFN) membranes were made using them. All the obtained membranes performance was studied in the forward osmosis (FO) process. The effects of the prepared compounds on the morphology, chemical structure, hydrophilicity, and topology of the polyamide (PA) active layer were evaluated by scanning electron microscopy (SEM), FT-IR spectroscopy, energy-dispersive X-ray (EDX), powder x-ray diffraction (XRD), water contact angle (WCA) goniometer and atomic force microscope (AFM) analysis. Finally, by comparing the results for both types of modified membranes, the membrane containing 0.025 wt% of the nanocomposite modifier showed the highest water flux (29.30 LMH) and selectivity (0.38 g/L) that was chosen as the optimal membrane. Also, the anti-fouling properties of this membrane were studied and the obtained results showed an increase in the fouling resistance compared to the membrane without filler. [ABSTRACT FROM AUTHOR]

Novel thin-film nanocomposite (TFN) membranes modified by the MoS 2 @Zeolite X nanocomposite were made and studied for desalination by the forward osmosis (FO) method. Herein, MoS 2 @Zeolite X nanocomposite (MoS 2 @Z) and zeolite X particles are integrated into the polyamide (PA) selective layer of the TFN membranes, separately. The aim of this study is the synthesis of nanocomposites containing hydrophilic zeolite X particles with a modified surface and pore and improvement of their effective properties on desalination and antifouling performance. For this purpose, MoS 2 nanosheets with a high hydrophilicity were selected. The existence of polymer-matrix-compatible MoS 2 @Z inside the PA active layer caused the formation of a defect-free smooth surface with further channels within this layer that could increase the water flux and fouling resistance of the TFN membranes. The TFN-MZ 2 membrane (containing 0.01 wt % MoS 2 @Z) showed the top desalination performance in the FO process. In contrast to the pristine thin-film composite (TFC) and TFN-Z 2 membrane (containing 0.025 wt % zeolite X, the most optimal membrane among the zeolite-modified membranes), its water flux has increased by 2.6 and 1.8 times, respectively. Furthermore, in the fouling test, this optimal TFN-MZ 2 membrane with a flux decrement of 19.6% revealed an ∼2.2- and 1.8-fold enhancement in antifouling tendency compared to the TFC and TFN-Z 2 , respectively. Also, based on the antibiofouling test, the water flux drop of 48.6% for the TFC membrane has reached 36.9% for the optimal membrane. Hence, this high-performance TFN-MZ 2 membrane shows good capability for commercial employment in FO desalination application.