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Recently utilization of nanoparticle incorporated polymer membranes for water treatment is in significant consideration. Herein we present the individual effect of graphene oxide (GO) and molybdenum disulfide (MoS2) nanosheets in altering the poly (amide imide) (PAI) membrane's hydrophilicity and thereby its separation efficiency and antifouling ability. The GO was characterized by Field Emission Scanning Electron Microscope (FESEM) and Raman spectroscopy. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction spectroscopy (XRD) were used to probe the existence of GO and MoS2 in PAI nanocomposite membranes. Contact angle (CA), pure water flux (PWF), water uptake, and porosity were measured to evaluate the enhancement in hydrophilicity of nanocomposite membranes. Top surface and cross-section morphology of the membranes were investigated by scanning electron microscopy (SEM). Antifouling capacity of the membranes was evaluated by fouling experiments using bovine serum albumin (BSA) and humic acid (HA) fouling agents. PAI-MoS2 nanocomposite membranes demonstrated better results in enhancing the membrane performance viz., superior PWF (105.6 Lm−2h−1), water uptake (80%) and porosity (21.2%), BSA and HA rejection (95.8 and 93.2%), FRR (90.5%), and slightly reduced hydraulic resistance ( R m ) and more reduced CA (64.8°) than that of PAI-GO nanocomposite membranes. The highly flexible and ultrathin MoS2 nanosheets with greater interaction between Mo and S atoms causes larger macrovoids in the bulk, and the sandwiched structure of MoS2 causes greater permeation. GO also improved PAI matrix to some extent due to its oxygen containing functional groups however several desirable and versatile characteristics of the MoS2 makes the PAI-MoS2 UF membranes as superior performer.

In this work, flat sheet polyacrylonitrile (PAN) based ultrafiltration (UF) membranes were fabricated by blending with amphiphilic copolymer Pluronic F127 (PF127) and inorganic calcium carbonate (CaCO 3 ) nanoparticles by nonsolvent induced phase inversion process which was employed as fouling resistant membranes for the separation of oil-water emulsion mixture. CaCO 3 nanoparticle was synthesized by controlled precipitation of saturated carbonate and calcium nitrate aqueous solution and was then confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD) and high-resolution transmission electron microscopy (HR-TEM). The fabricated membranes were characterized by attenuated total reflectance infrared spectroscopy (ATR-FTIR), thermal gravimetric analysis (TGA), mechanical analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM) analysis to study the effect on the addition of PF127 together with varying amount of CaCO 3 nanoparticle dosage on the membrane property. The filtration performances of the membranes were evaluated by measuring pure water flux, molecular weight cut off (MWCO), porosity and water content. The membrane hydrophilicity/hydrophobicity was examined through water contact angle measurement and separation efficacy was measured through ultrafiltration of oily feed solution. Membrane properties such as wettability, pure water permeability, mechanical strength, thermal stability, oil removal efficiency of the modified membrane was found to increase high upon addition of 0.75 wt% of CaCO 3 nanoparticle. Flux recovery was found to elevate from around 63% to 90% after a simple hydraulic wash indicating that the modified hybrid membranes were less susceptible to fouling. The increase in water permeability and antifouling property is ascribed the presence of large number of hydroxyl functional groups coupled with large number of small pores on the modified membrane surface.