Faculty Publications
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Item Humic Acid Based Biopolymeric Membrane for Effective Removal of Methylene Blue and Rhodamine B(American Chemical Society service@acs.org, 2015) Shenvi, S.S.; Isloor, A.M.; A.F., A.F.; Shilton, S.J.; Al-Ahmed, A.Humic acid was immobilized on a polypropylene supported sodium alginate/hydroxyethyl cellulose blend membrane in the current work. The adsorption property of this membrane for the removal of cationic dyes, namely, methylene blue (MB) and rhodamine B (RhB), was extensively studied. Batch-adsorption experiments were conducted to investigate the adsorption behavior of dyes on the membrane with variation in adsorbent mass, initial dye concentration, pH, time, and temperature. The membranes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM). Prepared membranes showed more than 98% removal capacity for both dyes under optimal conditions. Kinetic experiments revealed that the pseudo second order model exhibited the best correlation with the adsorption data. Dubinin-Radushkevich model indicated that the adsorption of dyes onto the membrane surface was by simple physisorption. The membrane was easily regenerated by simple acid treatment, and its efficiency remained significant even after four adsorption cycles. © 2015 American Chemical Society.Item Efficient treatment of hazardous reactive dye effluents through antifouling polyetherimide hollow fiber membrane embedded with functionalized halloysite nanotubes(Taiwan Institute of Chemical Engineers, 2017) Hebbar, R.S.; Isloor, A.M.; Zulhairun, A.K.; Sohaimi Abdullah, M.; A.F., A.F.A simple, efficient and scalable approach was developed for the fabrication of highly fouling resistance nanocomposite hollow fiber membranes with the aim of effective removal of environmentally detrimental reactive dyes. The naturally occurring halloysite nanotubes were functionalized via facile self-polymerization of m-aminophenol in mild acidic condition and employed as a hydrophilic additive. The chemical modification was confirmed by FTIR, TEM and energy dispersed X-ray (EDX) analysis. The hybrid nanocomposite membrane was prepared by dry–wet spin technique with different additive dosage. The resultant membrane was characterized in terms of contact angle, surface energy, porosity, zeta potential, elemental mapping and morphology. The permeation experiments illustrated superior water flux of 104.9 Lm?1 h?1 and 9.6% of irreversible fouling with more than 90.3% of flux recovery by the simple hydraulic cleaning. Most importantly, prepared membrane was subjected for hazardous reactive dye removal application with different experimental parameters. The hybrid membrane with 2 wt. % of additive concentration showed more than 97% and 94% for the Reactive Red 102 and Reactive Black 5 dyes respectively. This approach may also be very useful in developing high flux, fouling resistant ultrafiltration hollow fiber membranes for the other similar type applications such as hemodialysis membranes. © 2017 Taiwan Institute of Chemical EngineersItem Antibiofouling hollow-fiber membranes for dye rejection by embedding chitosan and silver-loaded chitosan nanoparticles(Springer Verlag, 2019) Kolangare, I.M.; Isloor, A.M.; Zulhairun, Z.A.; Kulal, A.; A.F., A.F.; Siddique, I.; Asiri, A.M.The removal of toxic dyes from the wastewater and industrial effluents is a major environmental challenge. Various techniques have been employed for the removal of dyes, including the application of nano-sized adsorbents, nanocomposite membranes and photodegradation. Membrane filtration is an alterntive but suffers from drawbacks such as fouling. Here we present a simple approach for the development of antibiofouling membranes based on chitosan. The application of chitosan-based nanoparticles as additives for wastewater treatment is poorly explored. The chitosan and silver-loaded chitosan nanoparticles were synthesized by ionic gelation method and incorporated to fabricate hollow-fiber membranes by dry–wet spinning technique. The prepared membranes were characterized by morphological study, permeability test, antibiofouling study and dye rejection study. The nanocomposite hollow-fiber membranes displayed superior performance than their pristine form. The incorporation of 0.30 weight percent of the chitosan and silver-loaded chitosan nanoparticles into the hollow-fiber membranes enhanced the antifouling property with flux recovery ratio of 81.21 and 86.13%, respectively. The dye rejection results showed maximum rejection of 89.27 and 86.04% for Reactive Black 5 and Reactive Orange 16, respectively. Hence, it can be concluded that hollow-fiber membranes with silver-loaded chitosan nanoparticles are pertinent in developing antibiofouling membranes for the treatment of industrial dye effluents. © 2018, Springer Nature Switzerland AG.Item Novel polyphenylsulfone (PPSU)/nano tin oxide (SnO2) mixed matrix ultrafiltration hollow fiber membranes: Fabrication, characterization and toxic dyes removal from aqueous solutions(Elsevier B.V., 2019) Nayak, M.C.; Isloor, A.M.; Siddique, I.; Balakrishna Prabhu, B.; Ismail, N.I.; Asiri, A.M.Novel polyphenylsulfone (PPSU)/nano tin oxide (SnO2) mixed matrix hollow fiber membranes (HFMs) were fabricated by dry-wet spinning via phase separation method. In the current research, reported the contrast between neat PPSU membrane and nanocomposite membranes (PPSU/SnO2), to determine the toxic reactive dyes namely, reactive black-5 (RB-5) and reactive orange-16 (RO-16) removal ability from the aqueous media. Scanning electron microscopy (SEM) was used to observe the HFMs cross-sectional morphological changes and surface roughness parameters of membranes were analyzed using atomic force microscopy (AFM). The surface wettability ability of HFMs was examined with a contact angle, water uptake, and porosity measurements. The cross-flow filter unit was engaged to quantify the water permeability, anti-fouling ability as well as the dye rejection ability of fabricated membranes. With increasing the SnO2 NPs wt% in PPSU polymer matrix the membrane performance was enhanced continuously, it became evident that the incorporated SnO2 NPs plays main role in membrane performance. Added, water-soluble poly (vinylpyrrolidone) (PVP) can also impact the pore morphology in membranes. At the end, PS-3 membrane exhibited lower contact angle (63.7 0), higher water uptake (74.8%), porosity (84.1%), pure water flux 362.9 L/m2 h, and high potential for dyes rejection application, of about >94% for RB-5, and >73% for RO-16 dye, respectively. From the preliminary results, it can be stated that the usage of SnO2 NPs in membrane technology become effective towards wastewater treatment. © 2019 Elsevier B.V.Item Poly(ionic liquid)-Based charge and size selective loose nanofiltration membrane for molecular separation(Elsevier B.V., 2021) Naik, N.S.; Padaki, M.; Isloor, A.M.; Nagaraja, K.K.; Vishnumurthy, K.A.Separation of chemicals using membranes in smaller size regimes is a much-complicated process. An ideal membrane for molecular separation should be more hydrophilic with well-defined pore sizes for ensuring the selectivity to give a maximum solvent flux. Here, we report a poly(itaconic acid-co-styrene-co-sulfobetaine vinylimidazole) (PIL)/PSf blend selective filtration membrane with nanochannels for superior molecular separation. FESEM images showed asymmetrical membrane structure with a dense upper layer on the hallow spherical sphere, though contact angle measurements reported improved membrane hydrophilicity. Newly developed loose nanofiltration membranes showed a superior removal performance of synthetic dyes based on their size and charge, such as congo red (2.5 × 0.7 nm2 size, 99%) and Eriochrome Black T (1.5 × 0.8 nm2 sizes, 99%). The passage of methyl orange (1.1 × 0.4 nm2) demonstrating an excellent molecular separation capability due to their stable networks of interconnected nanochannel and thin selective layer. The overall results are promising and paving the way for environmental friendly and energy-efficient separation of chemicals through membranes in industrial applications. © 2021Item 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 High performance 2D molybdenum MXene polyphenylsulfone membranes for boosting water flux and efficient removal of humic acid, antibiotic and dyes from wastewater(Elsevier B.V., 2025) Satishkumar, P.; Isloor, A.M.; Farnood, R.MXene, a leading two-dimensional material, is attracting scientists due to its rich polar surface termination and compatibility. Through the etching of an aluminum layer from Mo3AlC2, we have effectively produced molybdenum MXene Mo3C2Tx (where T stands for polar moieties like –OH and ?F) and used it to fabricate a new Mo3C2Tx embedded mixed matrix membrane. By the incorporation of highly hydrophilic Mo3C2Tx MXene into polyphenylsulfone (PPSU) membrane, its water flux tremendously increased to a peak value of 290 L m-2h?1 and is higher than 300 % compared to pristine polyphenylsulfone membrane without Mo3C2Tx MXene. Water contact angle study of Mo3C2Tx MXene embedded membranes showed improvement in hydrophilicity with an increase in its loading. Mo3C2Tx-PPSU membrane demonstrated appreciable antifouling nature and pollutant separation efficacy. The optimal membrane revealed 98.68 %, 96.7 %, 84.72 %, and 80.2 % removal of toxic contaminants like humic acid, RB 5 dye, RO 16 dye, and tetracycline antibiotic, respectively. This study offers a novel Mo3C2Tx embedded polyphenylsulfone membrane for wastewater treatment that eliminates potentially harmful humic acid, antibiotics, and dyes. © 2025Item Fabrication and incorporation of MIL-53(Fe)-zwitterionic brushes into PVDF thin film composite membranes for enhancing heavy metal/dye rejection from aqueous body(Elsevier B.V., 2025) Prabhakar, N.; Isloor, A.M.; Farnood, R.; Fauzi Ismail, A.The bioaccumulation of heavy metal ions is a serious concern for researchers. The dyes and heavy metal ions also aquatic life impacting the biodiversity adversely. Synthesis of novel MIL-53(Fe)-PSBMA particles, and its incorporation into PVDF-based thin-film composite membranes is the crux of this work. Firstly, H2N-MIL-53(Fe) was synthesized by metal displacement reaction which was then modified into MIL-53(Fe)-PSBMA brushes. The brushes were synthesized by atom transfer radical polymerization method. The amine groups of the NH2-MIL-53(Fe) help connecting the MOF to the polymeric moiety. The as-synthesized material and the fabricated TFCs were characterized by BET, FTIR, XRD, XPS, TGA, AFM, FE-SEM, zeta potential, and DLS particle sizer. The presence of sulphur groups on the XPS spectrum of modified MOF ensured the successful polymer grafting on it. Zwitterionic moieties have both positive and negative charges within a single molecule which gave a resultant zeta potential of ?13.1 mV for the brushes. A pure water flux of 26.32 Lm?2 h?1 and 97.33 %, 95.19 %, 82.06 %, and 78.47 % rejections for Pb2+, Hg2+, As3+, Cd2+ ions and 96.23 % and 94.04 % rejection for 100 ppm reactive black-5 and sunset yellow dyes respectively were obtained for the optimized membrane having 0.035 wt% loading of zwitterionic MOF. This result was attributed to the enhanced membrane hydrophilicity which was also correlated with contact angle and water uptake studies. © 2024 Elsevier B.V.Item A chicken egg white-based amyloid–graphitic carbon nitride composite-incorporated hollow fiber membrane for efficient removal of dyes and heavy metal ions present in water(Royal Society of Chemistry, 2025) Nayak, S.S.; Isloor, A.M.; A.F., A.F.Severe water pollution due to excessive industrialization is resulting in a pure water crisis for humans and other living beings. This growing crisis emphasizes the urgent need for advanced and efficient water purification technologies to mitigate pollution and ensure the availability of pure water. To address this issue, the current study focuses on the synthesis of a chicken egg white amyloid–graphitic carbon nitride composite (AM–CN) using graphitic carbon nitride (g-C3N4) and egg whites through environment friendly and simple techniques. These composites were further characterized using different analytical techniques such as BET, FTIR, XRD, SEM, and TEM to understand the structure of the composite. Furthermore, these composites were embedded into hollow fiber membranes, and later, these membranes were analyzed through AFM, SEM, and hydrophilicity studies to understand the character and structure of the membrane. The filtration performance of the membrane revealed that the membrane with the AM–CN composite demonstrated enhanced performance in both pure water permeability and pollutant removal capacity. Among the fabricated membranes, the neat membrane exhibited a pure water permeability of 81 L m?2 h?1 bar?1. In contrast, the highest permeability of 203 L m?2 h?1 bar?1 was exhibited by the M II membrane, therefore considering it as an optimized membrane. This optimized membrane also displayed the highest pollutant removal capacity of >99% for Congo red dye, >98% for Reactive black 5 and 88% for Reactive orange 16 dye. In the case of heavy metal ion removal, the same membrane displayed an impressive 99% removal of lead ions and 75% removal of mercury ions in the presence of humic acid. © 2025 The Royal Society of Chemistry.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.