Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
65 results
Search Results
Item Carbon-based nanocomposite membranes for water and wastewater purification(Elsevier, 2018) Gnani Peer Mohamed, G.P.S.; Isloor, A.M.; Yuliwati, E.; A.F., A.F.The carbon-based nanocomposite membranes are developing core technology for water and wastewater purification. These materials are broadly used in the fabrication of ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO) and evolving forward osmosis (FO) nanocomposite membranes as an additive. In this chapter, performance enhancement of nanocomposite membranes using carbon nanotubes (CNTs) and graphene oxide (GO), especially in the field of desalination, dye removal, oil/water separation and natural organic matter removal, is discussed. © 2019 Elsevier Inc. All rights reserved..Item Synthetic polymer-based membranes for dye and pigment removal(Elsevier, 2020) Gnani Peer Mohamed, G.P.S.; Isloor, A.M.; Lakshmi, B.The use of synthetic polymeric membranes to remove dyes and pigments from industrial wastewater is a growing technology. The toxic and nonbiodegradable nature of dyes and pigments in industrial wastewater influences the importance of the removal of those dyes and pigments. Conventional methods such as coagulation, the photocatalytic process, adsorption, ozonation, plasma treatment, electrochemical treatment, etc., are proposed. However, these methods are very time-consuming, use expensive catalysts, are difficult to scale up, and need secondary treatment. In recent times, a substantial number of attempts have been put forward to advance the performance of polymeric membranes for dye and pigment wastewater treatment. In this chapter, the recent progress on the use of polymeric membranes in processes such as nanofiltration, membrane distillation, and ultrafiltration for effective dye and pigment removal are discussed. © 2020 Elsevier Inc. All rights reserved.Item Advances of membrane technology in wastewater treatment(Elsevier, 2024) Deepthi, P.V.; Viji, K.; Vijesh, A.M.; Isloor, A.M.; Kumar, V.Pure water scarcity is becoming a real threat to the modern world. Rapid growth in the textile, paper, and printing industries has caused the production of large quantities of dye effluents, and they must be treated before passing to the water bodies or lands to minimize pollution and environmental impacts. Polymeric membrane-based filtration has been established as an optimal and greener approach for removing hazardous dyes from polluted water. Superior thermal, chemical, and mechanical properties and convenient modifiability made polysulfone (PSF), polyethersulfone (PES), and polyphenylsulfone (PPSU) ideal for the production of membranes for the treatment of dye effluents from industries. This chapter emphasizes the recent developments in modified PSF, PES, and PPSU membranes and their dye rejection properties. © 2025 Elsevier Inc. All rights reserved.Item Separation of dimethyl phenol using a spiral-wound RO membrane - Experimental and parameter estimation studies(2009) Srinivasan, G.; Sundaramoorthy, S.; Murthy, D.V.R.Reverse osmosis (RO) is increasingly used as a separation technique in chemical and environmental engineering for the removal of organics and organic pollutants present in waste water. Treatment of organics by RO is dependent on many factors and hence developing a viable RO system involves extensive pilot-plant studies. The removal of an organic compound, namely dimethyl phenol, using a polyamide membrane was investigated in this study. Experiments were conducted on a laboratory-scale spiral-wound RO module. The permeate concentrations and rejection coefficient values were measured for various transmembrane pressures and feed concentrations. A maximum rejection of 97% was observed. A mathematical model was developed for the RO module assuming a solution-diffusion mechanism for solute and solvent transport through the membrane and considering the concentration and pressure to be uniform on both permeate and retentate sides. The model has four parameters. A graphical method for estimating the model parameters was proposed. The model and the estimated parameter values were validated with the experimental data. The model was able to predict the permeate concentration within an error of 19% and rejection within 2% error. © 2009.Item Polysulfone/N-phthaloylchitosan novel composite membranes for salt rejection application(2011) Padaki, M.; Isloor, A.M.; Wanichapichart, P.N-phthaloylchitosan (CS) was synthesized by the reaction of chitosan with phthalic anhydride in dimethyl formamide. Different compositions of polysulfone (PSf) and N-phthaloylchitosan were used to prepare novel polysulfone/N-phthaloylchitosan (PSf/CS) composite membranes by phase inversion method. The composition ratios between the former and the latter were 80:20, 85:15, 90:10, and 95:5. Water flux results revealed that, PSf:CS 80:20 membrane is found to have greatest effective pore area while PSf:CS 95:05 membrane has the smallest value. The pore area is found to be larger with the increase in CS composition. In addition, its water swelling property increases with the increase of CS composition. Water flux results are in consistent with dielectric constant value. Use of known molecular weight of polyethylene glycol rejection study, revealed that, PSf:CS 95:05 membrane possessed the smallest pore size among these membranes. In conclusion, change of ratio between PSf and CS, considerably affects membrane pore size and hydrophilicity. For salt filtration, membrane PSf:CS 95:05 showed 93%, 76.11% and 70.12% rejection of MgSO4, Na2SO4, and NaCl, respectively. © 2011 Elsevier B.V.Item Influence of nanoscale NiO on magnetic and electrochemical behavior of PVDF-based polymer nanocomposites(2012) Bhatt, A.S.; Bhat, D.K.New poly(vinylidene fluoride) (PVDF)/NiO-based polymer nanocomposites were prepared by phase inversion method, using dimethyl formamide as solvent and deionized water as non-solvent. The structure and porous morphology of the membranes were studied by field emission scanning electron microscopy. The presence of NiO resulted in overall decrease in porosity and crystallinity of the nanocomposite membranes. Using electrochemical impedance spectroscopy, a maximum ionic conductivity of 1.08 × 10 -3 S cm -1 was obtained for PVDF membrane with 1 wt% content of NiO. The good efficiency of conductivity observed in the membrane was explained on the basis of decrease in crystallinity and movement of charge carriers in NiO structure. The magnetization of nanocomposite membranes gradually increased with increase in NiO content. © 2011 Springer-Verlag.Item Synthesis, characterization and desalination study of novel PSAB and mPSAB blend membranes with Polysulfone (PSf)(2012) Padaki, M.; Isloor, A.M.; A.F., A.F.; Abdullah, M.S.The present paper describes the synthesis of poly sulphonyl amino benzamide (PSAB) and methyalated poly sulphonyl amino benzamide (mPSAB) polymer, using terephthalic acid chloride and substituted 4-amino-1-benzensulphonmide in N-methyl-. 2-pyrrolidone. Polymers were characterized by FT-IR, NMR and GPC. Polysulfone composite membranes were prepared using these novel poymers by DIPS (Diffusion Induced Phase Seperation) method. These composite membranes are useful for water purification with special emphasis on sea water desalination. Newly prepared membranes were studied for salt rejection, water flux, molecular weight cut off by PEG solution, effect of the pH on water swelling and salt rejection and flux decline was also studied. 30 to 70% of the salt rejection was observed in all membranes. Effect of the dilution on salt rejection was studied using different concentration of NaCl solution varying from 1000. ppm to 3500. ppm. All the membranes showed 80% rejection for PEG having 1000. Da molecular weight. Contact angle and water swelling was measured to determine hydrophilicity of the membrane. Water swelling and salt rejection in different pH was also studied. © 2012 Elsevier B.V.Item Preparation and characterization of sulfonated polysulfone and N-phthloyl chitosan blend composite cation-exchange membrane for desalination(2012) Padaki, M.; Isloor, A.M.; Wanichapichart, P.; A.F., A.F.Sulfonated polysulfone (sPSf) was prepared and used as a polymer matrix for cation-exchange membranes (CEM). The sulfonation reaction was carried out at room temperature and the degree of sulfonation was calculated by titration method. Blend composite membranes were prepared using different ratios of sPSf and modified chitosan (CS). Membrane properties were studied in terms of water flux, water swelling ratio, molecular weight cut off (MWCO), ion-exchange capacity (IEC) and contact angle measurement. Charge on the membrane was confirmed by ionic diffusion potential (DP). It was observed that, DP increased with the increase in the concentration of sPSf. The membrane sPSf:CS 60:40 showed 1000Da MWCO, 14.6mV diffusion potential (DP) and 0.083mM/g of IEC. Similarly sPSf:CS 90:10 showed 10,000Da MWCO, 71.7mV diffusion potential (DP) and 0.176mM/g of IEC. Moreover, membrane sPSf:CS 60:40 showed 93%, 89% and 69% for MgSO 4, Na 2SO 4 and NaCl rejection respectively. © 2012 Elsevier B.V.Item Preparation and characterization of polysulfone and modified poly isobutylene-alt-maleic anhydride blend NF membrane(2012) Ganesh, B.M.; Isloor, A.M.; Padaki, M.Recently nanofiltration (NF) is gaining more importance for water treatment. It is replacing the conventional method of water treatment due to advantages of NF membranes over RO system. In this work, we are discussing the preparation of NF membrane for desalination of sea water. We herein report the synthesis of polymer, by the reaction of p-amino benzoic acid (PABA) and poly isobutylene-alt-maleic anhydride (PIAM) and its blend membrane preparation with polysulfone (PSf). The new membranes were characterized by SEM images, surface wettability to investigate the hydrophilic nature of the membrane, water swelling, pure water flux, molecular weight cut-off and salt rejection of the membranes. The membranes showed nano size (<50nm) pores in SEM image, and the contact angle data revealed that membrane surface is moderately hydrophilic. Membrane with 70:30 (PSf:modified PIAM) composition has shown good salt rejection of 96% at 200kPa for 3500ppm of NaCl solution with a pure water flux of 38.36Lm -2h -1. © 2011 Elsevier B.V.Item Fabrication and high-temperature structural characterization study of porous anodic alumina membranes(2012) Choudhari, K.S.; Sudheendra, P.; Udayashankar, N.K.Porous anodic alumina (PAA) membranes with highly ordered array of nanopores were prepared by twostep anodization process. Studies on structural and thermal properties and the thermal stability of the prepared PAA membranes were carried out. Investigation using scanning electron microscopy, atomic force microscopy, X-ray diffraction, thermal analysis and infrared spectroscopy was performed on the prepared PAA membranes at room temperature and in the temperature range 600-1,400 °C. The as-prepared PAA membranes revealed the amorphous nature. Polycrystalline PAA membranes were obtained by annealing carried out at different temperatures. Annealing study confirmed that the heat treatment transformed the amorphous PAA membranes to their crystalline phases, namely, ?-alumina at about 870 °C and then to ?-alumina around 1,250 °C. © Springer Science+Business Media, LLC 2011.