Journal Articles

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(2E)-3-(6-Methoxynaphthalen-2-yl)-1-[4-(methylsulfanyl)phenyl] prop-2-en-1-one
(2012) Fun, H.-K.; Chia, T.S.; Padaki, M.; Isloor, A.M.; A.F., A.F.
The asymmetric unit of the title compound, C21H 18O2S, consists of two crystallographically independent molecules (A and B). The molecules exist in a trans conformation with respect to the central C=C bond. The naphthalene ring system makes dihedral angles of 51.62 (12) (molecule A) and 52.69 (12)°(molecule B) with the benzene ring. In molecule A, the prop-2-en-1-one group forms dihedral angles of 22.84 (15) and 29.02 (12)°with the adjacent naphthalene ring system and benzene ring, respectively, whereas the corresponding angles are 30.04 (12) and 23.33 (12)°in molecule B. In the crystal, molecules are linked by intermolecular C - H?O hydrogen bonds into head-to-tail chains along the a axis. The crystal packing also features C - H?? interactions. The crystal studied was a pseudo-merohedral twin with twin law (100 01?0 001?) and a refined component ratio of 0.6103 (16):0.3897 (16). © 2012 International Union of Crystallography.
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.
A review on RO membrane technology: Developments and challenges
(Elsevier B.V., 2015) Shenvi, S.S.; Isloor, A.M.; A.F., A.F.
Reverse osmosis (RO) based desalination is one of the most important and widely recognized technologies for production of fresh water from saline water. Since its conception and initiation, a significant development has been witnessed in this technology w.r.t. materials, synthesis techniques, modification and modules over the last few decades. The working of a RO plant inclusive of the pretreatment and post-treatment procedures has been briefly discussed in the article. The main objective of this review is to highlight the historical milestones achieved in RO technology in terms of membrane performance, the developments seen over the last few years and the challenges perceived. The material properties of the membrane dominate the performance of a RO process. The emergence of nano-technology and biomimetic RO membranes as the futuristic tools is capable of revolutionizing the entire RO process. Hence the development of nano-structured membranes involving thin film nano-composite membranes, carbon-nanotube membranes and aquaporin-based membranes has been focussed in detail. The problems associated with a RO process such as scaling, brine disposal and boron removal are briefed and the measures adopted to address the same have been discussed. © 2014 Elsevier B.V.
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.
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.
Bio-inspired, fouling resistant, tannic acid functionalized halloysite nanotube reinforced polysulfone loose nanofiltration hollow fiber membranes for efficient dye and salt separation
(Elsevier Ltd, 2017) Gnani Peer Mohamed, G.P.S.; Isloor, A.M.; Moslehyani, A.; A.F., A.F.
Superficial functionalization of the hollow fiber membrane with progressive nanomaterials exhibits increased hydrophilicity, outstanding selectivity, and permeability. In the present study, a simple and novel loose nanofiltration (NF) membranes were prepared by the addition of tannic acid functionalized halloysite nanotubes (THNTs) in polysulfone (PSf) membrane matrix via phase inversion method. The successful modification of halloysite (HNTs) was confirmed by FT-IR, zeta potential measurement, TGA, TEM and EDX analysis. The membrane permeation studies were carried out with a sequence of salts (NaCl and Na2SO4) and dyes (reactive black 5 and reactive orange 16). The resulted membranes exhibited increased hydrophilicity, porosity, water uptake, antifouling performance, along with higher dye rejection (>99% for reactive black 5 and >90% of reactive orange 16) and low salt rejection (2.5% of NaCl and 7.5% of Na2SO4) properties. The nanocomposite membrane also exhibited the highest pure water flux of 92 L/m2 h compared to the pristine membrane of 18 L/m2 h made it a worthy candidate for the wastewater purification. © 2017 Elsevier Ltd
Effect of binary zinc-magnesium oxides on polyphenylsulfone/cellulose acetate derivatives hollow fiber membranes for the decontamination of arsenic from drinking water
(Elsevier B.V., 2021) Kumar, M.; Isloor, A.M.; Todeti, S.R.; Nagaraja, H.S.; A.F., A.F.; Susanti, R.
Arsenic contamination is continuously threatening the safety of drinking water in many parts of the world. The consumption of chronic arsenic contaminated drinking water can cause serious health related issues. Therefore, the synthesis of novel materials is very much essential for the selective removal of arsenic from aqueous solution. In the present investigation, the effect of increased concentrations (0.6, 1.0 and 1.5 wt%) of binary zinc-magnesium oxide (ZnO-MgO) on cellulose acetate (CA)/polyphenylsulfone (PPSU) and cellulose acetate phthalate (CAP)/PPSU hollow fiber membranes for arsenic removal was performed. As used ZnO-MgO was characterized by using x-ray diffraction (XRD), transmission electron microscopy (TEM) and particle size distribution. Fabricated hollow fiber membranes were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), zeta potential, fourier transform infrared (FTIR), x-ray photoelectron spectrophotometer (XPS), thermogravimetric analysis (TGA) and antifouling studies. The results revealed that, there is significant enhancement in the overall performance of the ZnO-MgO containedmembranes. An enhancement of arsenic removal properties was demonstrated from 0.6 wt% of ZnO-MgO in CAP/PPSU (ZMCAP-0.6) membrane was 81.31% with the retention permeability of 69.58 L/m2h bar respectively. Similarly, 1 wt% of ZnO-MgO in CA/PPSU (ZMCA-1) was found to be 78.48% and 198.47 L/m2h bar respectively using 1 ppm laboratory prepared aqueous arsenic solution (pH 6.8 ± 0.2) at 1 bar transmembrane pressure. In addition, improved antifouling properties was noticed with an increased flux recovery ratio and enhanced thermal stability from ZnO-MgO contained membranes. Therefore, as fabricated ZnO-MgO contained membranes provided enhanced arsenic removal tendency without compromising the retention permeability. © 2020
Effective separation of agrochemicals and textile dyes from polluted aqueous solution employing ternary ZnCoFe layered double hydroxide incorporated polyethersulfone hollow fiber ultrafiltration membrane
(Elsevier B.V., 2025) Pallot, H.; Isloor, A.M.; A.F., A.F.
The rapid urbanization and industrialization has increased the contamination of water bodies with agrochemical residues and textile dyes, which poses a severe threat to environmental and human health, necessitating the need of an efficient water purification strategies. Membrane-based filtration techniques has grown significantly due to the demand for sustainable and effective water treatment. For the first time, ternary ZnCoFe layered double hydroxides (LDH) modified polyethersulfone hollow fiber ultrafiltration membrane was developed for enhancing hydrophilicity and separation efficiency of dyes and agrochemicals. The widespread use and long-term persistence in the water bodies of Reactive Orange 16, Crystal Violet, chlorpyrifos and 2,4-dichlorophenoxy acetic acid (2,4-D) highlight the critical need for the effective removal of these pollutants. ZnCoFe LDH was developed by the co-precipitation method with a 2:2:1 M ratio of nitrates of Zn, Co, and Fe transition metals. The membranes were fabricated with different composition of LDH. The influence of LDH in the membranes was assessed through FESEM, AFM, zeta potential, contact angle, water uptake capacity, porosity, water permeability, and molecular weight cut-off. The incorporation of ZnCoFe-LDH into the PES membrane resulted in an improved pure water flux, rising from 91.03 Lm?2 h?1 for the pristine (MLZ-0) membrane to 143.25 Lm?2 h?1 for the optimized (MLZ-2). The optimized membrane exhibits a good antifouling property with flux recovery ratio improved from 52.13 to 64.18%. The rejection of Reactive Orange 16 and Crystal Violet was found to be 74.9% and 79.8% for MLZ-0 whereas for MLZ-2 the values were 83.2% and 99.1% respectively. MLZ-2 also exhibited 47.1% and 90.9% for 2,4-D and chlorpyrifos rejection respectively while pristine membrane showed 22.7% and 78.8%. © 2025 Elsevier B.V.
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.
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 Engineers
Engineering hollow fiber membranes with poly-m-aminophenol functionalized graphitic carbon nitride for efficient water purification
(Elsevier B.V., 2025) Nayak, S.S.; Isloor, A.M.; Todeti, S.R.; A.F., A.F.
Water pollution caused by industrialization poses a great threat to the living organisms mainly due to the release of dye wastewater and pollutants into the water bodies. Ingestion of such polluted water has detrimental effects on living organisms. To address the issue, the present study focuses on the synthesis of poly-m-aminophenol functionalized graphitic carbon nitride (FCNs) using inexpensive graphitic carbon nitride and m-aminophenol. The synthesized FCNs were characterized with FTIR, XPS, XRD, TGA, DTA, Zeta potential, Particle size, TEM and BET analysis. These FCNs were further incorporated into the hollow fiber membrane and subsequently analyzed using SEM, AFM, Zeta potential, Hydrophilicity, and performance studies. Among the fabricated membranes, the optimized CN-AP 50 membrane exhibited enhanced an average water permeability of 150 Lm-2 h?1 bar ?1 and a Flux recovery ratio of 49.9 % with 11.9 % of reversible fouling. Furthermore, the membrane also displayed excellent dye rejection capacity of >99 % for Congo red, >98 % for Reactive black 5, and 86 % for Reactive orange 16. Additionally, it showed impressive heavy metal ion removal capability of 99 % for lead ions and 60 % for mercury ions in the presence of humic acid. These enhanced rejection and water permeability are due to the various effects such as improved hydrophilicity, electrostatic interaction between functional groups, ?-? interaction with the dye molecules. These effects also modify the membrane morphology thereby enhancing size exclusion and adsorption capabilities. The present study discusses a strategy for incorporating poly-m-aminophenol functionalized graphitic carbon nitride as an additive in membrane fabrication. The functionalized material improves water permeability, antifouling performance, and membrane selectivity, thus offering a scalable route for advanced wastewater treatment technologies. © 2025
Enhanced hydrophilicity and salt rejection study of graphene oxide-polysulfone mixed matrix membrane
(2013) Ganesh, B.M.; Isloor, A.M.; A.F., A.F.
Graphene oxide (GO) dispersed polysulfone (PSf) mixed matrix membranes were prepared by wet phase inversion method. The morphology of membranes was studied using scanning electron microscope (SEM) images. The variation in hydrophilicity was studied by measuring surface wettability and water swelling experiments. The performance of membranes in terms of pure water flux and salt rejection was studied. SEM images depict enhanced macrovoids, while the contact angle data reveals that, GO incorporated membrane surface is moderately hydrophilic. Membranes exhibited improved salt rejection after GO doping. Membrane with 2000ppm GO loading has exhibited maximum of 72% Na2SO4 rejection at 4bar applied pressure. The salt rejection seems to depend on pH of the feed solution and it has been witnessed that the salt rejection showed an increasing trend with increase in the pH. © 2012 Elsevier B.V.
Enhanced permeation performance of cellulose acetate ultrafiltration membranes by incorporation of sulfonated poly(1,4-phenylene ether ether sulfone) and poly(styrene- Co -maleic anhydride)
(American Chemical Society service@acs.org, 2014) Shenvi, S.; A.F., A.F.; Isloor, A.M.
A cellulose acetate (CA)-based ultrafiltration membrane was prepared by incorporation of mechanically strong, sulfonated poly(1,4-phenylene ether ether sulfone) (SPEES) to which hydrolyzed poly(styrene-co-maleic anhydride) (PSMA) was added as a novel additive. The preparation of SPEES was investigated in detail. SPEES having a degree of sulfonation of 21%, was more suitable for the blend. The chemical constitutions of SPEES, PSMA, and the blend membranes were confirmed by attenuated total reflectance fourier transform infrared spectroscopy. The scanning electron microscopy images revealed finger-like projections in the membrane structure. The performance of the membranes was analyzed on the basis of water content, porosity, flux, and antifouling studies. A membrane comprising 30% SPEES and 2% additive showed superior performance with flux and flux recovery ratio of 228 L/(m2 h) and 91%, respectively. It was concluded that the prepared membranes showed better performance in comparison with neat CA membranes. © 2014 American Chemical Society.
Fabrication and characterization of new PSF/PPSU UF blend membrane for heavy metal rejection
(Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2016) Moideen K, I.; Isloor, A.M.; A.F., A.F.; AlObaid, A.; Fun, H.-K.
Polysulfone and polyphenylsulfone-blend ultrafiltration membranes of different compositions were prepared by the phase inversion method, with and without hydrophilic additive poly (ethylene glycol) 1,000 (PEG). The membrane morphology was studied using scanning electron microscope, which displayed the asymmetric structure of the membrane. The hydrophilicity of the membranes was measured by contact angle, porosity, water uptake, and permeability studies. The blend membrane showed enhanced permeability, hydrophilicity, and antifouling property as compared to the pristine polymer membrane. The pure water flux of the membrane, which was blended with PEG additive was relatively higher than the blend membranes without the additive. The flux recovery ratio (FRR) was measured to study the antifouling property. The membranes with PEG additive exhibited better antifouling property with maximum FRR of 72.84%. The heavy metal rejection by the membrane was carried out by complexing the metal ions with polyethyleneimine, which exhibited highest rejection of 99.48 and 95.5% of Pb2+ and Cd2+, respectively. © 2015 Balaban Desalination Publications. All rights reserved.
Fabrication of a novel hollow fiber membrane decorated with functionalized Fe2O3 nanoparticles: Towards sustainable water treatment and biofouling control
(Royal Society of Chemistry, 2017) Hebbar, R.S.; Isloor, A.M.; Kulal, K.; Abdullah, M.S.; A.F., A.F.
The development of sustainable, surface-functionalized hollow fiber membranes with advanced nanomaterials has enabled the tailoring and targeted control of their physicochemical properties. This provides the material with improved features of hydrophilicity and permeability, excellent selectivity, and superior antifouling and antimicrobial activity. We explored a new strategy using well dispersed functionalized Fe2O3 nanoparticles to fabricate a polyetherimide nanocomposite hollow fiber membrane with enhanced surface and anti-biofouling properties. To confirm the membrane modification, a series of characterizations such as contact angle, surface energy, water uptake capacity, porosity, zeta potential, and morphological analysis were performed. The permeation experiment indicated superior hydrodynamic permeability and antifouling properties with more than 95% rejection of BSA protein molecules after inclusion of a 1.5 wt% additive dosage. Moreover, the nanocomposite membrane exhibited a relatively higher normalized flux and rejection up to 94% during the filtration of hazardous natural organic matter (NOM) with differing parameters such as the feed solution pH and ionic strength. The presence of modified Fe2O3 nanoparticles in the membrane significantly inhibits the growth of bacteria and other microorganisms on the membrane surface, resulting in an enhanced anti-biofouling property. In particular, the demonstrated method illustrates a fast, facile strategy for the functionalization of Fe2O3 nanoparticles to improve the membrane properties and anti-biofouling activity, giving them great potential for effective and sustainable water treatment applications. © 2017 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Fabrication of novel PPSU/ZSM-5 ultrafiltration hollow fiber membranes for separation of proteins and hazardous reactive dyes
(Taiwan Institute of Chemical Engineers, 2018) Nayak, M.C.; Isloor, A.M.; Moslehyani, A.; Ismail, N.; A.F., A.F.
Polyphenylsulfone (PPSU) based asymmetric hollow fiber membranes were prepared by the addition of different percentages of ZSM-5 particles by diffusion induced phase separation method. Polyvinylpyrrolidone (PVP) was used as a pore forming agent. The fabricated membranes were characterized by Field Emission scanning electron microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), contact angle, water permeability, water uptake and by porosity measurements. Membranes filtration study was performed using different proteins namely bovine serum albumin (BSA), egg albumin (EA) and hazardous dyes like Reactive black 5 (RB-5), Reactive orange 16 (RO-16) in aqueous solutions. It was found that, addition of ZSM-5 in membrane matrix showed better dye removal capacity because of its hydrophilic and adsorptive nature. The membrane (PZ-3) with higher loading of additive exhibited rejection percentages of 100% for BSA, 95.23% for EA proteins and with reactive dyes 90.81% for RB-5 and 82.84% for RO-16 as compared to the pristine HF membrane. © 2017 Taiwan Institute of Chemical Engineers
Fabrication of polydopamine functionalized halloysite nanotube/polyetherimide membranes for heavy metal removal
(Royal Society of Chemistry, 2016) Hebbar, R.S.; Isloor, A.M.; Kulal, K.; A.F., A.F.
Polydopamine modified halloysite nanotubes (HNTs) were synthesised through a one step facile procedure and employed as a well dispersed hydrophilic additive to enhance the filtration properties of polyetherimide (PEI) membranes. The nanocomposite membranes were prepared by an immersion precipitation method with different amounts of modified HNTs (MHNTs) in the casting solution. The good dispersion of MHNTs throughout the membrane matrix was confirmed by elemental mapping analysis. The prepared nanocomposite membranes were extensively studied in terms of their porosity, morphology, membrane hydraulic resistance and hydrophilicity. The permeation experiments showed that the modified membranes exhibited higher water flux than a pristine PEI membrane. The antifouling and anti-biofouling behaviour of the modified membranes was investigated in detail. The results revealed that a membrane with a 3 wt% MHNT dosage showed a higher Fouling Resistance Ratio (FRR) of 74.5% with reversible membrane fouling of 64.3%. Moreover, the membrane showed excellent resistance to microbial growth on the membrane surface. The well performing membrane was subjected to heavy metal ion rejection. Results indicated that membranes had the capacity to adsorb Pb2+ and Cd2+. Overall, PEI-MHNTs nanocomposite membranes could have great potential to improve antifouling, anti-biofouling and filtration properties. © The Royal Society of Chemistry 2016.
Fabrication of polyetherimide nanocomposite membrane with amine functionalised halloysite nanotubes for effective removal of cationic dye effluents
(Taiwan Institute of Chemical Engineers, 2018) Hebbar, R.S.; Isloor, A.M.; Siddique, I.; Abdullah, M.S.; A.F., A.F.; Asiri, A.M.
Naturally, occurring, low cost and eco-friendly halloysite nanotubes were chemically modified and uniformly immobilised into the polyetherimide membrane matrix with the aim of enhancing the properties and possible cationic dye rejection efficacy. The properties of fabricated nanocomposite membranes were examined by means of porosity, hydrophilicity, zeta potential and permeability. Permeation experiments revealed the enhanced water flux up to 195 L/m2h with 4 wt% additive dosage. The dye rejection efficacy of the prepared membranes was determined by using rhodamine B (Rh.B) and methylene blue (MB). The dye rejection studies were executed in terms of pH, contact time and initial dye concentration. The membrane with 4 wt% of nanomaterial dosage, showed rejection of 97% at pH 8 and 94% at pH 7 for MB and Rh.B dyes, respectively. Langmuir adsorption isotherm is the best model to explain interaction between dye molecules and membrane surface, with quantity of dye adsorbed (qmax) was observed to be 20.4 mg/g and 19.6 mg/g for MB and Rh.B, respectively. This approach showed modified membrane has good cationic dye rejection efficacy and can be efficiently employed to remove the dyes from aqueous streams. © 2018 Taiwan Institute of Chemical Engineers
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.
Hydrophilic nano-aluminum oxide containing polyphenylsulfone hollow fiber membranes for the extraction of arsenic (As-V) from drinking water
(Elsevier Ltd, 2021) Kumar, M.; Isloor, A.M.; Todeti, S.R.; A.F., A.F.; Farnood, R.
In the present work, hollow fiber ultrafiltration membranes were fabricated by incorporating intensified dosages of nano?aluminum oxide (nano-Al2O3; 0.6 wt%, 1.0 wt% and 1.5 wt%) into cellulose acetate (CA)/polyphenylsulfone (PPSU) and cellulose acetate phthalate (CAP)/PPSU by non-solvent induced phase separation (NIPS) process. The topological structures and the morphologies were investigated using atomic force microscope (AFM) and scanning electron microscope (SEM). The crystalline and morphological structures of the nano-Al2O3 were investigated using X-ray diffraction (XRD) and transmission electron microscope (TEM) respectively. Fourier transform infra-red spectroscope (FTIR) and x-ray photoelectron spectroscopy (XPS) analysis have been carried out to validate the dosages of nano-Al2O3, CA and CAP on PPSU membranes. The membrane's surface charge measurement of 1.5 wt% of nano-Al2O3 in CA/PPSU (ALCA-1.5) was scrutinized by zeta potential analysis. Membranes removed more arsenate oxide as the removal rate from membranes ALCA-1.5 and 1.0 wt% of nano-Al2O3 in CA/PPSU (ALCA-1) was 98.67% and 94.89% with retention permeabilities of 88.41 L/m2h bar and 53.53 L/m2h bar respectively from laboratory prepared 1 ppm of aqueous arsenic solution with pH in the range 6.8 ± 0.2 at 1 bar transmembrane pressure. In addition, membrane's antifouling analysis was performed using laboratory prepared 0.8 g/L (Bovine Serum Albumin) BSA as standard protein solution. © 2021 Elsevier Ltd