Faculty Publications
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Item Antifouling and performance enhancement of polysulfone ultrafiltration membranes using CaCO3 nanoparticles(2013) Nair, A.K.; Isloor, A.M.; Kumar, R.; A.F., A.F.Calcium carbonate nanoparticles were synthesized from calcium nitrate via chemical precipitation method. The nanoparticles were characterized using scanning electron microscope (SEM), Attenuated total reflectance infra red (ATR-IR) spectrum and by X-ray diffraction (XRD). These nanoparticles were used as additive for polysulfone (PSf) ultrafiltration membrane along with polyethylene glycol (PEG) as pore forming agent. The PSf hybrid membranes were characterized by ATR-IR, XRD, and SEM studies. ATR-IR and XRD results indicated the successful incorporation of the nanoparticles in the membranes. Cross sectional images of the membranes along with the elemental mapping of calcium on the membrane surface were assessed using SEM. Hydrophilicity of the membranes was evaluated in terms of contact angle measurements. The permeability of the membranes was determined by measuring the pure water flux (PWF). Membranes were also subjected to antifouling studies using bovine serum albumin (BSA) as the standard protein for rejection. The membranes showed better permeability and antifouling property with the increased addition of CaCO3 nanoparticles. © 2013 Elsevier B.V.Item Fabrication of TiO2@ZIF-67 metal organic framework composite incorporated PVDF membranes for the removal of hazardous reactive black 5 and Congo red dyes from contaminated water(Elsevier B.V., 2024) Prabhakar, N.; Isloor, A.M.; Padaki, M.; Fauzi Ismail, A.Novel application of TiO2@ZIF-67 composite incorporated poly (vinylidene fluoride) (PVDF) mixed matrix flat-sheet membranes for treating the water contaminated with hazardous reactive black 5 and congored dyes was the crux of this work. The composite was characterized by FTIR, BET, XRD, zeta potential and particle size, and TGA. The as-synthesized composite was embedded in the PVDF polymeric matrix and flat-sheet-membranes were fabricated adopting the NIPS method followed by the different characterizations like scanning electron microscopy, EDS, elemental mapping, contact angle, atomic force microscopy, surface energy, and XPS. Results of the performance studies showed an enhanced pure water permeability from 150.99 Lm-2h?1 for neat membrane to 261.39 Lm-2h?1 for TZM-2. The reactive black 5 dye was rejected in 97.4 %, 92.2 %, and 84.84 % in acidic, basic and neutral conditions respectively by TZM-2 membrane. Whereas, the PVDF membranes without the composite showed rejections of 83.19 %, 82.5 %, and 72.1 % respectively in acidic, basic, and neutral conditions. The Congo Red dye was rejected in 89.4 %, 95.68 %, and 92.4 % in acidic, neutral and basic conditions respectively by TZM-2 membranes. Whereas, the PVDF membranes without the composite showed rejections of 82.8 %, 91.9 %, and 85.4 % respectively in acidic, neutral and basic conditions. © 2024Item Efficient removal of hazardous dyes/heavy-metal ions by in-house fabricated poly (vinylidene fluoride) thin-film nanocomposite membranes with functionalized Zr-based metal-organic framework(Elsevier Ltd, 2025) Prabhakar, N.; Isloor, A.M.; Farnood, R.; A.F., A.F.The need for effective solutions to address removal of dyes and heavy metal ions from water has driven significant interest in membrane science and separation technology. This work explores the potential of EDTA-modified MOF-808 as a novel additive to enhance the performance of PVDF supported TFC membranes. The innovation lies in aiming the unique properties of MOF and the chelating properties of EDTA in rejecting the target pollutants. The thin film nanocomposite membranes fabricated in this study with optimized MOF-EDTA loading demonstrated remarkable improvement in hydrophilicity, surface smoothness, porosity, and morphology as confirmed by water contact angle, atomic force microcopy, water uptake, and scanning electron microscopy. The optimized membrane with 0.1wt% MOF-808-EDTA exhibited a water flux of 37.36 Lm-2h-1, a 2.7-fold increment compared to the unmodified one. This was complemented by 98.6%, 91.48%, 88.7%, and 88.96% rejections in hazardous heavy metal ions namely lead, arsenite, cadmium and mercury respectively along with more than 95% rejections for 50ppm of sunset yellow and reactive black 5 dyes. The study also highlights the significant enhancement in antifouling properties with a reduction in irreversible fouling from 41.5% to 5.68% along with a flux rejection ratio of 94.3%. These findings underscore the potential of EDTA-modified MOF as an additive in enhancing the performance and durability of TFC membranes paving the way for efficient and sustainable water treatment. The current study explores an innovative approach for mitigating heavy metal ion and dye pollution in water via fabrication of. © 2025 Published by Elsevier Ltd.Item Polydopamine functionalized halloysite nanotubes incorporated polyethersulfone hollow fiber membranes for the removal of arsenic (as-v) from water(Iranian Research Organization for Science and Technology, 2025) Mruthyunjaya, S.D.; Isloor, A.M.; Nayak, S.S.; Venkatesh, M.; Shetti, V.S.Polyethersulfone (PES) based hollow fiber membranes containing polydopamine-functionalized halloysite nanotubes (FHNTs) were fabricated in different concentrations employing a dry-wet approach and using phase inversion methodology. Thus, the prepared nanocomposite hollow fiber membranes were characterized using FE-SEM (Field Emission Scanning Electron Microscopy), AFM (Atomic Force Microscopy), ATR-IR, Zeta Potential, and contact angle for studying membrane surface morphology, topography, presence of functional groups, surface charge, and hydrophilicity, respectively. Filtration studies such as pure water permeability, fouling resistance, and heavy metal rejection (arsenic) were performed at a 2 bar pressure. It was found that as the concentration of FHNTs increased in the membrane, the pure water flux also increased, indicating an increase in hydrophilicity. The membrane PPD-4, with the highest percentage of FHNTs, showed the maximum heavy metal removal. It was confirmed by the values of arsenic removal by the membranes containing FHNTs at 0 wt%, 0.2 wt%, 0.6 wt%, and 1 wt% that were found to be 24.80%, 33.18%, 35.54%, and 39.65%, respectively. © 2024 Advances in Environmental Technology (AET).Item Sustainable waste water purification via integration of novel COF@UiO-66 dual-layer PVDF/PEI hollow fiber membranes(Elsevier B.V., 2025) Prabhakar, N.; Isloor, A.M.; Othman, M.H.D.; A.F., A.F.In the present study, dual-layer (polyvinylidene fluoride (PVDF)/ polyether imide (PEI) blend membranes were fabricated by coextrusion technique, with varying loadings (0–1.5 wt%) of covalent organic framework (COF) grafted UiO-66, for dye and heavy metal ion removal. UiO-66-NH2 was chosen for its excellent surface area and water stability, which can enhance the water permeability through the membrane without getting degraded over a period of time. The structures of the synthesized UiO-66-NH2 and COF@UiO-66 were confirmed by characterizations like scanning electron microscopy (SEM), FTIR (Fourier Transform Infrared Spectroscopy), and XRD (X-ray Diffraction). The membrane fabricated with the synthesized additive in the outer layer, was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM) for the surface topography and morphology. The incorporation of the additive significantly affected the hydrophilicity, porosity, and surface area of the membrane, resulting in improved permeability and rejection, along with imparting relatively good antifouling nature to the membrane. Membrane with outer dope flow rate of 2 mL/min and an optimized loading of the additive (1.0 wt.%) displayed a water permeability of 117.5 Lm?2 h?1 bar?1, whereas the neat membrane showed only 60 Lm?2 h?1 bar?1. The dyes, Congo red and reactive black-5, showed rejections of 99.1 %, and 97.96 % respectively. Whereas, the heavy metal ions mercury and lead showed 69.58 %, and > 99.9 % in the complexed state with humic acid for the optimized membrane, along with a bovine serum albumin (BSA) fouling rejection ratio of 74.22 %. Whereas the neat membrane without the MOF additive showed 89 %, 79 %, 75 %, and 43 % rejections for reactive black 5, congo red, lead, and mercury ions, respectively, with an FRR of only 57 %. © 2025 Elsevier B.V.