Faculty Publications
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Item Novel hybrid photocatalytic reactor-UF nanocomposite membrane system for bilge water degradation and separation(Royal Society of Chemistry, 2015) Moslehyani, A.; A.F., A.F.; Othman, M.H.D.; Isloor, A.M.This study focuses on the design and performance of a hybrid system consisting of a photocatalytic reactor and ultrafiltration permeation cell. Initially, an ultraviolet (UV) lamp was installed in the photocatalytic reactor to decompose the bilge organic pollutants in the presence of 200 ppm titanium-dioxide (TiO2). Individual hydrocarbon compounds of bilge water samples were identified by gas chromatography-mass spectrometry (GC-MS) analysis. Two types of membrane, which are a pure polyvinylidene fluoride (PVDF) membrane and PVDF/modified halloysite nanotube clay (M-HNTs) nanocomposite membrane were fabricated aiming to enhance the rejection, flux and fouling resistance for full filtration of pollutants from the photocatalytic reactor. The membranes were characterized by Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Furthermore, GC-MS analysis showed that, over 90% bilge decomposition occurred by a photocatalytic reaction. The TiO2 cross-over during permeation was detected by using an atomic absorption spectrophotometer (AAS), which proved that, TiO2 rejection was more than 99% for the nanocomposite membrane. A UV- vis spectrophotometer confirmed over 99% rejection of decomposed bilge hydrocarbons via the nanocomposite membrane with 1.0 wt% of M-HNTs incorporated in the PVDF matrix. This journal is © The Royal Society of Chemistry 2015.Item 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.Item Photoreactor-ultrafiltration hybrid system for oily bilge water photooxidation and separation from oil tanker(Elsevier, 2016) Moslehyani, A.; Mobaraki, M.; Isloor, A.M.; A.F., A.F.; Othman, M.H.D.A novel design of hybrid system consisting of photoreactor (PR) combined with ultrafiltration (UF) membrane was investigated for oily bilge water degradation and separation from oil tanker. Initially, the bilge organic compounds were photooxidized using ultraviolet type A (UVA) light irradiation on 100, 200 and 300 ppm of TiO2. Further TiO2 and oxidized oily bilge water was filtered using hollow fiber membrane separator, which was prepared by polyvinylidene fluoride (PVDF) and halloysite nanotubes. The hollow fiber membranes were characterized by ATR-IR spectrum, thermal gravimetric analysis (TGA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscope (XPS). Individual hydrocarbon of oily bilge water was identified by using gas chromatography-mass spectrometry (GC-MS) analysis. According to the GC-MS analysis, over 90% decomposition of oil in bilge water has occurred by 200 and 300 ppm of TiO2 suspension. On the other hand, pH meter showed that, decomposed oily bilge water was more acidic, which increased to pH 7 after UF system process. Moreover, over 99% of degraded oil in bilge water was filtered by this promising hybrid system. © 2016 Elsevier B.V. All rights reserved.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 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