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Hollow fiber nanofiltration: From lab-scale research to full-scale applications. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.121234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Amphiphilic antifouling membranes by polydopamine mediated molecular grafting for water purification and oil/water separation. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119306] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Assessment of interfacial polymerization modalities on the performance of polyaniline doped polyethersulphone hollow fiber membranes. J Appl Polym Sci 2021. [DOI: 10.1002/app.50485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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5
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Graphene oxide interlayered thin-film nanocomposite hollow fiber nanofiltration membranes with enhanced aqueous electrolyte separation performance. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117153] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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6
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Nanofiltration thin‐film composite membrane on either the internal or the external surface of a polysulfone hollow fiber. AIChE J 2020. [DOI: 10.1002/aic.16970] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Thin Film Composite and/or Thin Film Nanocomposite Hollow Fiber Membrane for Water Treatment, Pervaporation, and Gas/Vapor Separation. Polymers (Basel) 2018; 10:E1051. [PMID: 30960976 PMCID: PMC6403908 DOI: 10.3390/polym10101051] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/20/2018] [Accepted: 09/04/2018] [Indexed: 11/16/2022] Open
Abstract
Thin film composite (TFC) polymeric hollow fiber (HF) membranes are widely used in industrial gas/vapor separations and water treatment. There are many advantages of TFC HF membranes, such as low energy requirements, simplicity of operation, and high specificity. In the present article, a review is made on the progress that has been achieved during the past 15 years in the preparation of the HF substrate and the preparation/modification of the thin selective layer. The review also includes their applications in water treatment, dehydration of alcohols via pervaporation, and gas/vapor separation.
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Performance and Morphology Evaluation of Thin Film Composite Polyacrylonitrile/Polyamide Nanofiltration Membranes Considering the Reaction Time. J WATER CHEM TECHNO+ 2018. [DOI: 10.3103/s1063455x18040070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Elevated-Temperature 3D Printing of Hybrid Solid-State Electrolyte for Li-Ion Batteries. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1800615. [PMID: 30132998 DOI: 10.1002/adma.201800615] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/15/2018] [Indexed: 06/08/2023]
Abstract
While 3D printing of rechargeable batteries has received immense interest in advancing the next generation of 3D energy storage devices, challenges with the 3D printing of electrolytes still remain. Additional processing steps such as solvent evaporation were required for earlier studies of electrolyte fabrication, which hindered the simultaneous production of electrode and electrolyte in an all-3D-printed battery. Here, a novel method is demonstrated to fabricate hybrid solid-state electrolytes using an elevated-temperature direct ink writing technique without any additional processing steps. The hybrid solid-state electrolyte consists of solid poly(vinylidene fluoride-hexafluoropropylene) matrices and a Li+ -conducting ionic-liquid electrolyte. The ink is modified by adding nanosized ceramic fillers to achieve the desired rheological properties. The ionic conductivity of the inks is 0.78 × 10 -3 S cm-1 . Interestingly, a continuous, thin, and dense layer is discovered to form between the porous electrolyte layer and the electrode, which effectively reduces the interfacial resistance of the solid-state battery. Compared to the traditional methods of solid-state battery assembly, the directly printed electrolyte helps to achieve higher capacities and a better rate performance. The direct fabrication of electrolyte from printable inks at an elevated temperature will shed new light on the design of all-3D-printed batteries for next-generation electronic devices.
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Evaluation of fluoride bioremediation and production of biomolecules by living cyanobacteria under fluoride stress condition. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 148:26-36. [PMID: 29031116 DOI: 10.1016/j.ecoenv.2017.10.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/05/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
Application of microalgae for defluoridation has gained interest in recent years. In the present study, bioremediation of fluoride using living cyanobacteria, Starria zimbabweensis, collected from wastewater of coke-oven effluent treatment plant, Durgapur, India, has been investigated. Initially, the cyanobacterial strain was grown in BG11 medium at 25°C, 45μmol/m2/s irradiation in 18h: 6h light:dark cycle in an algal incubator. Samples were withdrawn after 2 days interval and analyzed for its dry biomass and lipid content. Optimum inoculum size of 10% and age of 16th day were assessed based on maximum dry biomass (9.307 ± 0.01g/L) and lipid (244.05 ± 0.02mg/L) production. SEM-EDX and FTIR studies of both native and fluoride treated biomass were done to emphasize the changes. During kinetic study of defluoridation, initial fluoride concentration was varied in the range of 10-50mg/L. Maximum fluoride removal (66.6 ± 0.11%) and dry biomass (18.19 ± 0.12g/L) were obtained at 10mg/L fluoride concentration using 10% of 16th day's inoculum. Biomass and lipid content were found to increase 2 and 4 folds, respectively under fluoride stress condition. Furthermore, chlorophyll, carbohydrate and protein content of the biomass were also compared between control and fluoride contaminated conditions. Fatty Acid Methyl Ester (FAME) analysis was done using Gas Chromatography (GC) to compare the lipid profile of native and fluoride loaded strain.
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Adsorption isotherms and kinetic studies for the defluoridation from aqueous solution using eco-friendly raw marine green algae, Ulva lactuca. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 190:14. [PMID: 29234975 DOI: 10.1007/s10661-017-6392-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 12/05/2017] [Indexed: 06/07/2023]
Abstract
The defluoridation from aquatic medium by raw marine algae, Ulva lactuca, was investigated. The element components and adsorbent's properties were determined. The influence of pH, contact period, and Ulva sp. weight on the deflouridation was achieved. The complete defluoridation of 10 mg F-/l solution was obtained within 10 min at definite pHs. Fourteen adsorption isotherms and four kinetic models (pseudo-first order and pseudo-second order, Elovich, and intraparticle diffusivity) were studied. The most adequate model was performed by using five error functions. The application of chi-squared test indicated that the nonlinear isotherm models (two and three parameters) were more applicable than the linear ones. The adsorption kinetic proceeded by pseudo-first-order model. The adsorption mechanism was very complex; thus, the solute distribution step was not the only dominant one during the process. The adsorption seemed to be a physical negative binding cooperative type with activation energy and free energy of 3.16 and - 1.672 kJ/mol, respectively. Thus, raw marine algae, Ulva lactuca, can be used as an adsorbent in solving the fluoridation problem in aquatic mediums throughout the world due to their fast procedure, high efficiency, low effort, and high economic value.
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Poly(piperazine-amide)/PES Composite Multi-Channel Capillary Membranes for Low-Pressure Nanofiltration. Polymers (Basel) 2017; 9:polym9120654. [PMID: 30965955 PMCID: PMC6418675 DOI: 10.3390/polym9120654] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/23/2017] [Accepted: 11/24/2017] [Indexed: 11/17/2022] Open
Abstract
The mechanical stability of conventional single-channel capillary fibres can be improved in a multi-channel geometry, which has previously found application in ultrafiltration. In this work, multi-channel polyethersulfone (PES) capillary membranes comprising seven feed channels were successfully fabricated in an enhanced steam–dry–wet spinning process and coated on the inner surface with a thin polyamide (PA) layer via interfacial polymerization (IP). The coating procedure consisted of impregnating the support multi-channel capillary membranes (MCM) with an aqueous piperazine solution, flushing with nitrogen gas to remove excess droplets, and pumping an organic trimesoylchloride solution through the channels. Insights into the interfacial polymerization process were gained through the investigation of various parameters, including monomer ratio, contact time, and drying time. Membranes were characterised via scanning electron microscopy (SEM), atomic force microscopy (AFM), and filtration experiments. The optimisation of both the PES support membrane and IP process parameters allowed for the fabrication of composite MCM with an MgSO4 rejection of 91.4% and a solute flux of 68.8 L m−2 h−1 at an applied pressure of 3 bar. The fabricated composite MCM demonstrates that a favourable multi-channel arrangement can be upgraded with a PA layer for application in low-pressure nanofiltration.
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A review on semi-aromatic polyamide TFC membranes prepared by interfacial polymerization: Potential for water treatment and desalination. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.03.020] [Citation(s) in RCA: 156] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Hollow fiber nanofiltration membranes: A comparative review of interfacial polymerization and phase inversion fabrication methods. SEP SCI TECHNOL 2017. [DOI: 10.1080/01496395.2017.1321668] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Design and fabrication of inner-selective thin-film composite (TFC) hollow fiber modules for pressure retarded osmosis (PRO). Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2016.08.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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A comparative study of removal of fluoride from contaminated water using shale collected from different coal mines in India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:9418-9431. [PMID: 26620857 DOI: 10.1007/s11356-015-5815-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Accepted: 11/16/2015] [Indexed: 06/05/2023]
Abstract
Low-cost water defluoridation technique is one of the most important issues throughout the world. In the present study, shale, a coal mine waste, is employed as novel and low-cost adsorbent to abate fluoride from simulated solution. Shale samples were collected from Mahabir colliery (MBS) and Sonepur Bazari colliery (SBS) of Raniganj coalfield in West Bengal, India, and used to remove fluoride. To increase the adsorption efficiency, shale samples were heat activated at a higher temperature and samples obtained at 550 °C are denoted as heat-activated Mahabir colliery shale (HAMBS550) and heat-activated Sonepur Bazari colliery shale (HASBS550), respectively. To prove the fluoride adsorption onto different shale samples and ascertain its mechanism, natural shale samples, heat-activated shale samples, and their fluoride-loaded forms were characterized using scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction study, and Fourier transform infrared spectroscopy. The effect of different parameters such as pH, adsorbent dose, size of particles, and initial concentration of fluoride was investigated during fluoride removal in a batch contactor. Lower pH shows better adsorption in batch study, but it is acidic in nature and not suitable for direct consumption. However, increase of pH of the solution from 3.2 to 6.8 and 7.2 during fluoride removal process with HAMBS550 and HASBS550, respectively, confirms the applicability of the treated water for domestic purposes. HAMBS550 and HASBS550 show maximum removal of 88.3 and 88.5 %, respectively, at initial fluoride concentration of 10 mg/L, pH 3, and adsorbent dose of 70 g/L.
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Novel high-flux thin film composite nanofiltration membranes fabricated by the NaClO pre-oxidation of the mixed diamine monomers of PIP and BHTTM in the aqueous phase solution. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2015.12.031] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Novel polyamide thin-film composite nanofiltration membrane modified with poly(amidoamine) and SiO2 gel. RSC Adv 2016. [DOI: 10.1039/c6ra05716k] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Recently, poly(amidoamine) (PAMAM) has emerged as a novel material due to its high density of functional groups, hyper-branched structure and hydrophilic nature.
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A chlorine-tolerant nanofiltration membrane prepared by the mixed diamine monomers of PIP and BHTTM. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2015.10.028] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Removal of fluoride from polluted waters using active carbon derived from barks of Vitex negundo plant. J Anal Sci Technol 2015. [DOI: 10.1186/s40543-014-0042-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Deleterious effects of fluoride contamination in ground waters on the health of human beings are well known and intensive research on developing de-fluoridation methods is globally pursued. Of the various methodologies, increasing interest is being envisaged in using the adsorption methods based on active carbons derived from plant material. In the present investigation, Nitric acid activated carbon derived from barks of Vitex negundo plant (NVNC) is probed for its de-fluoridation abilities.
Methods
The activated carbon is characterized adopting various physicochemical methods and surface morphological studies are carried out using FT-IR and SEM-EDX techniques. The effect of various parameters such as pH, sorbent dosage, agitation time, initial concentration of fluoride, temperature, particle size and presence of foreign ions on the extraction of the fluoride is studied adopting Batch methods.The adsorption process is analyzed with Freundlich, Langmuir, Temkin and Dubinin-Radushkevich (D-R) isotherms and kinetics of adsorption is studied using pseudo first-order, pseudo second-order, Weber and Morris intraparticle diffusion, Bangham’s pore diffusion and Elovich equations. The methodology developed is applied to real ground water samples.
Results
De-fluoridation is maximum at the pH: 7.0, adsorbent dosage: 4.0g/lit; equilibrium time: 50 min, Particle size: 45μ and temperature: 30 ± 1°C. The correlation coefficient values for the adsorption isotherms: Freundlich, Langmuir, Temkin and Dubinin-Radushkevich are 0.929, 0.998, 0.980 and 0.946 respectively and for kinetic models: pseudo-first-order, pseudo-second-order, Weber and Morris intraparticle diffusion, Bangham’s pore diffusion and Elovich equations are 0.989, 0.994, 0.874, 0.902 and 0.912 respectively. The Temkin heat of sorption, B, and the Dubinin-Radushkevich mean free energy, E, for the activated carbon adsorbent are 0.196 J/mol and 7.07 kJ/mol respectively.
Conclusions
Nitric acid activated carbon derived from barks of Vitex negundo (NVNC) plant is found to be an effective adsorbent for the de-fluoridation of waters. The adsorption process is satisfactorily fitted with Langmuir adsorption isotherm with good correlation coefficient value and it indicates monolayer adsorption. The adsorption kinetics is found to follow pseudo-second-order kinetics. The Dubinin-Radushkevich mean free energy and Temkin heat of sorption confirm the physisorption nature as these are lower than 20kJ/mol. The procedure developed is remarkably successful in de-fluoridation of real ground water samples.
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Recent Advances in Polymeric Solvent-Resistant Nanofiltration Membranes. ADVANCES IN POLYMER TECHNOLOGY 2014. [DOI: 10.1002/adv.21455] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Role of wettability in interfacial polymerization based on PVDF electrospun nanofibrous scaffolds. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2013.04.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Newly developed nanofiltration (NF) composite membranes by interfacial polymerization for Safranin O and Aniline blue removal. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2012.12.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Interfacially polymerized composite nanofiltration hollow fiber membranes for low-pressure water softening. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2012.12.011] [Citation(s) in RCA: 179] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Synthesis of 4-Aminobenzoylpiperazine for Preparing the Thin Film Composite Nanofiltration Membrane by Interfacial Polymerization with TMC. SEP SCI TECHNOL 2013. [DOI: 10.1080/01496395.2012.685546] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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28
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Ultra-thin hybrid polyhedral silsesquioxane–polyamide films with potentially unlimited 2D dimensions. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm31941a] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Fluoride Removal by Lanthanum Alginate Bead: Adsorbent Characterization and Adsorption Mechanism. Chin J Chem Eng 2011. [DOI: 10.1016/s1004-9541(09)60222-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Formation and structural evolution of biphenyl polyamide thin film on hollow fiber membrane during interfacial polymerization. J Memb Sci 2011. [DOI: 10.1016/j.memsci.2011.02.045] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Preparation of Thin Film Composite Nanofiltration Membrane by Interfacial Polymerization with 3,5-Diaminobenzoylpiperazine and Trimesoyl Chloride. Chin J Chem Eng 2011. [DOI: 10.1016/s1004-9541(11)60163-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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32
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Fabrication of novel poly(amide–imide) forward osmosis hollow fiber membranes with a positively charged nanofiltration-like selective layer. J Memb Sci 2011. [DOI: 10.1016/j.memsci.2010.11.067] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Fluoride adsorption studies on mixed-phase nano iron oxides prepared by surfactant mediation-precipitation technique. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:1751-1757. [PMID: 21232851 DOI: 10.1016/j.jhazmat.2010.12.076] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 11/22/2010] [Accepted: 12/15/2010] [Indexed: 05/30/2023]
Abstract
Mixed nano iron oxides powder containing goethite (α-FeOOH), hematite (α-Fe(2)O(3)) and ferrihydrite (Fe(5)HO(8)·4H(2)O) was synthesized through surfactant mediation-precipitation route using cetyltrimethyl ammonium bromide (CTAB). The X-ray diffraction, FTIR, TEM, Mössbauer spectroscopy were employed to characterize the sample. These studies confirmed the nano powder contained 77% goethite, 9% hematite and 14% ferrihydrite. Fluoride adsorption onto the synthesized sample was investigated using batch adsorption method. The experimental parameters chosen for adsorption studies were: pH (3.0-10.0), temperature (35-55°C), concentrations of adsorbent (0.5-3.0 g/L), adsorbate (10-100 mg/L) and some anions. Adsorption of fluoride onto mixed iron oxide was initially very fast followed by a slow adsorption phase. By varying the initial pH in the range of 3.0-10.0, maximum adsorption was observed at a pH of 5.75. Presence of either SO(4)(2-) or Cl(-) adversely affected the adsorption of fluoride in the order of SO(4)(2-)>Cl(-). The FTIR studies of fluoride loaded adsorbent showed that partly the adsorption on the surface took place at surface hydroxyl sites. Mössbauer studies indicated that the overall absorption had gone down after fluoride adsorption that implies it has reduced the crystalline bond strength. The relative absorption area of ferrihydrite was marginally increased from 14 to 17%.
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Study on a novel polyester composite nanofiltration membrane by interfacial polymerization. II. The role of lithium bromide in the performance and formation of composite membrane. J Memb Sci 2010. [DOI: 10.1016/j.memsci.2010.09.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Fluoride adsorption onto granular ferric hydroxide: effects of ionic strength, pH, surface loading, and major co-existing anions. JOURNAL OF HAZARDOUS MATERIALS 2009; 171:774-779. [PMID: 19616377 DOI: 10.1016/j.jhazmat.2009.06.079] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 06/12/2009] [Accepted: 06/15/2009] [Indexed: 05/28/2023]
Abstract
Fluoride adsorption onto granular ferric hydroxide (GFH) was investigated using batch methods, under various ionic strength, pH, surface loading, and major co-existing anion conditions. Adsorption of fluoride on GFH included an initial fast adsorption phase followed by a slow adsorption phase. Within the pH range of 2-11, fluoride adsorption equilibrium was not affected by ionic strength, but was significantly affected by pH. Maximum adsorption was achieved in the pH range of 3-6.5. Under the same pH condition, fluoride adsorption followed the Freundlich isotherm, indicating that the GFH surface was heterogeneous. X-ray photoelectron spectroscopy (XPS) and attenuated total reflection-infrared (ATR-IR) spectroscopy data showed evidence for fluoride sorption on the GFH surface via inner-sphere complexation accompanying increased hydrogen bonding and surface hydroxylation. Major anions, including phosphate, bicarbonate, sulfate, and chloride, reduced fluoride adsorption in the following order: H(2)PO(4)(-)>HCO(3)(-)>SO(4)(2-)>Cl(-).
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