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Application of face-centered central composite design (FCCCD) in optimization of enzymatic decolorization of two azo dyes: A modeling vs. empirical comparison
, Article Progress in Color, Colorants and Coatings ; Volume 12, Issue 3 , 2019 , Pages 179-190 ; 20082134 (ISSN) ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
Institute for Color Science and Technology
2019
Abstract
Biological treatment, especially enzymatic methods, can be employed for effective and environmental- friendly treatment of dye effluents. Laccase, belonging to the blue multi-copper oxidases category, can oxidize a wide variety of substrates, especially synthetic dyes. In this study, laccase was used to biodegrade two azo dyes, i.e., Direct Red 23 and Acid Blue 92. Before conducting the experiments, the laccase used in this study was enzymatically characterized. Face-centered central composite design (FCCCD) was used to optimize the main parameters of the decolorization process. The optimum conditions to maximize the bio-decolorization process of AB92 were X1=11.85 mg L-1, X2=5.10, and...
Photochemical oxidation of Reactive blue 19 dye (RB19) in textile wastewater by UV/K2S2O8 process
, Article Iranian Journal of Environmental Health Science and Engineering ; Volume 5, Issue 2 , 2008 , Pages 95-100 ; 17351979 (ISSN) ; Ghaneian, M. T ; Khavanin, A ; Hashemian, S. J ; Moussavi, G. H ; Ghanizadeh, G. H ; Hajizadeh, E ; Sharif University of Technology
2008
Abstract
In textile industry, advanced oxidation processes are used for degrading and removing color from dye baths which allow wastewater reuse. In this study, photochemical oxidation processes (UV-A/K2S2O8, UV-C/ K2S2O8) and chemical oxidation process (dark/K2S2O8), were investigated in a laboratory scale photoreactor for decolorization of the Reactive blue 19 (RB19) dye from synthetic textile wastewater. The effects of operating parameters such as potassium persulphate dosage, pH, reaction time and UV source, on decolorization have been evaluated. The results of direct chemical oxidation showed that 50% of the dye was been removed using K2S2O8 in dark condition after 5h reaction time and...
Assessment of luminescent downshifting layers for the improvement of light-harvesting efficiency in dye-sensitized solar cells
, Article ChemPhysChem ; Vol. 15, issue. 17 , 2014 , pp. 3791-3799 ; ISSN: 14394235 ; Diau, E. W. G ; Mehrany, K ; Taghavinia, N ; Sharif University of Technology
Abstract
Luminescence downshifting (LDS) of light can be a practical photon management technique to compensate the narrow absorption band of high-extinction-coefficient dyes in dye-sensitized solar cells (DSSCs). Herein, an optical analysis on the loss mechanisms in a reflective LDS (R-LDS)/DSSC configuration is reported. For squaraine dye (550-700 nm absorption band) and CaAlSiN3:Eu2+ LDS material (550-700 nm emission band), the major loss channels are found to be non-unity luminescence quantum efficiency (QE) and electrolyte absorption. By using an ideal LDS layer (QE=100 %), a less absorbing electrolyte (Co-based), and antireflection coatings, approximately 20% better light harvesting is obtained....
Direct dyes removal using modified magnetic ferrite nanoparticle
, Article Journal of Environmental Health Science and Engineering ; Vol. 12, Issue. 1 , 28 May , 2014 ; ISSN: 2052336X ; Abdi, J ; Bastani, D ; Sharif University of Technology
Abstract
The magnetic adsorbent nanoparticle was modified using cationic surface active agent. Zinc ferrite nanoparticle and cetyl trimethylammonium bromide were used as an adsorbent and a surface active agent, respectively. Dye removal ability of the surface modified nanoparticle as an adsorbent was investigated. Direct Green 6(DG6), Direct Red 31 (DR31) and Direct Red 23 (DR23) were used. The characteristics of the adsorbent were studied using Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effect of adsorbent dosage, initial dye concentration and salt was evaluated. In ternary system, dye removal of the adsorbent at 90, 120, 150 and 200 mg/L...
Molecular engineering of bithiazole-based organic dyes with different electron-rich linkers toward highly efficient dye-sensitized solar cells
, Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 349 , 2017 , Pages 171-182 ; 10106030 (ISSN) ; Hadipour, N. L ; Parsafar, G ; Sharif University of Technology
Abstract
A series of bithiazole-based dye sensitizers have been designed by employing various electron-rich moieties as π-spacer, which are based on the reported experimentally synthesized dye T-BT, to shed a light on the impact of both the nature and position of electron-rich moiety on the efficiency of dyes in DSSCs. To evaluate the efficiency of these dyes, various key parameters associated with overall conversion efficiency (η), including electronic and optical properties of free dyes are calculated, based on the computational methods. Besides, the dye/TiO2 structures have been taken into account to investigate the interfacial features of the dye sensitizers adsorbed on TiO2 semiconductor and...
Improving dye removal and antifouling performance of polysulfone nanofiltration membranes by incorporation of UiO-66 metal-organic framework
, Article Journal of Environmental Chemical Engineering ; Volume 10, Issue 3 , 2022 ; 22133437 (ISSN) ; Mousavi, S. A ; Shokrgozar, A ; Mousavi, D. V ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In the present work, a series of polysulfone (PSf) mixed-matrix nanofiltration membranes containing highly water stable UiO-66 metal-organic framework (MOF) were prepared via a simple phase inversion technique. At first, UiO-66 particles were synthesized via a solvothermal technique, activated via two various activation methods, including Soxhlet extraction and centrifugation methods. Then their adsorption performance was investigated for adsorption of anionic methyl orange (MO)/methyl red (MR) and cationic methylene blue (MB)/malachite green (MG) dyes from water. The activated UiO-66 particles via the Soxhlet extraction method (named S-UiO-66) showed better performance for dye adsorption...
Photocatalytic Treatment of Azo based Textile Pollutants by Modified Bismuth Vanadate
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manoochehr (Supervisor) ; Ghasemi, Shahnaz (Co-Supervisor)
Abstract
In recent years, because of the increase in population and more accessibility of health facilities for people, an increase has occurred in water resources consumption. Recycling water has become so much valuable as the freshwater of the world is limited. Besides the advantages of treated water has for people, discharging the untreated wastewater to the rivers could cause many problems for human health. Many kinds of pollutions, such as textile effluent, are not easy to be treated by traditional methods because of their resistance to them. As these types of wastewater have severe negative effects on living things (both humans and animals), new treatment technologies should be considered. The...
Investigation of the antibacterial and photocatalytic properties of the zeolitic nanosized AgBr/Tio2 composites
, Article Materials Science in Semiconductor Processing ; Volume 15, Issue 1 , February , 2012 , Pages 73–79 ; Elahifard, M. R. (Mohammad Reza) ; Vatan Meidanshahi, R. (Reza) ; Ghasemi, S. (Shahnaz) ; Haghighi, S. (Saeed) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
Abstract
Zeolite-based Ag/AgBr and Ag/AgBr/TiO2 photocatalysts were prepared by sol–gel and deposition methods and were characterized. Their photocatalytic activities were evaluated by inactivation of Escherichia (E.) coli and the photodegradation of Acid Blue 92 and potassium permanganate. The composites containing Ag/AgBr showed the antibacterial activity in the dark by releasing Ag+ ions into the medium. The results for inactivation of E. coli indicated that Ag/AgBr/TiO2 modified photocatalyst had better antibacterial activity than Ag/AgBr/zeolite, while zeolite and TiO2/zeolite did not show any antibacterial activity under visible light and dark conditions. Photodecolarization rate was affected...
Recent developments in dye-sensitized solar cells
, Article ChemPhysChem ; Vol. 15, issue. 18 , Dec , 2014 , p. 3902-3927 ; Tajabadi, F ; Taghavinia, N ; Sharif University of Technology
Abstract
The knowledge of dye-sensitized solar cells (DSCs) has expanded considerably in recent years. They are multiparameter and complex systems that work only if various parameters are tuned simultaneously. This makes it difficult to target to a single parameter to improve the efficiency. There is a wealth of knowledge concerning different DSC structures and characteristics. In this review, the present knowledge and recent achievements are surveyed with emphasis on the more promising cell materials and designs
FeCl2/FeCl3 perlite nanoparticles as a novel magnetic material for adsorption of green malachite dye
, Article Arabian Journal for Science and Engineering ; Volume 39, Issue 5 , May , 2014 , Pages 3383-3392 ; ISSN: 13198025 ; Doulati Ardejani, F ; Badii, K ; Seifpanahi Shabani, K ; Mousavi, S. E ; Sharif University of Technology
Abstract
In this research FeCl2/FeCl3/Perlite magnetic nanoparticles (FeCl2/FeCl3/PMNs), as a novel magnetic nanocomposite adsorbent was used for the removal of green malachite (GM) dye from aqueous solution in a batch and fixed bed column. Firstly, FeCl2/FeCl3/PMNs adsorption properties were investigated. Therefore, the solution of FeCl2·4H2O and FeCl3·6H2O by ratio 2/1 was mixed with perlite nanoparticles. The study investigates the effect of process parameters such as pH, adsorbent dosage, contact time and GM dye initial concentration. Next, GM dye was quantitatively evaluated by using the Langmuir, Freundlich and BET isotherms and pseudo-first- and pseudo-second-order kinetic model. The...
Improved efficiency of dye-sensitized solar cells based on a single layer deposition of skein-like TiO 2 nanotubes
, Article Journal of the American Ceramic Society ; Vol. 97, issue. 9 , 2014 , pp. 2873-2879 ; ISSN: 00027820 ; Mohammadi, M. R ; Madaah Hosseini, H. R ; Sharif University of Technology
Abstract
We present a new TiO2 morphology, featuring high surface area and open structure, synthesized by a two-step chemical route for the manufacture of dye-sensitized solar cells (DSSCs). This construct is sets of intertwined one-dimensional (1D) nanostructures (i.e., nanotubes), so-called skein-like nanotubes (NTs). Such morphology is produced by a combination of TiC oxidation and hydrothermal processes. The mesoporous TiO2 nanoparticles, as the product of TiC oxidation operation, is used as the precursor of hydrothermal process to grow the skein-like NTs. The effect of processing parameters of TiC oxidation and hydrothermal processes is studied. The skein-like morphology enables to eliminate the...
Adsorption characteristics of malachite green dye onto novel kappa-carrageenan-g-polyacrylic acid/TiO2-NH2 hydrogel nanocomposite
, Article Journal of the Iranian Chemical Society ; Volume 11, Issue 4 , August 2014 , Pages 1057-1065 ; Doulabi, M ; Doroudian, M ; Sharif University of Technology
Abstract
Batch adsorption experiments were carried out for the removal of malachite green (MG) cationic dye from aqueous solution using novel hydrogel nanocomposite that was prepared by graft copolymerization of acrylic acid (AA) onto kappa-carrageenan (κC) biopolymer in the presence of a crosslinking agent, a free radical initiator and aminosilica-functionalized TiO2 nanoparticles (κC-g-PAA/TiO2-NH2). The factors influencing adsorption capacity of the adsorbents such as initial pH value (pH0) of the dye solutions, TiO2-NH2 content (wt%), initial concentration of the dye, amount of adsorbents, and temperature were investigated. The adsorption capacity of hydrogel nanocomposite for MG was compared...
Double-Layer TiO2 Electrodes with Controlled Phase Composition and Morphology for Efficient Light Management in Dye-Sensitized Solar Cells
, Article Journal of Cluster Science ; Vol. 25, issue. 4 , 2014 , p. 1029-1045 ; Mohammadi, M. R ; Fray, D. J ; Sharif University of Technology
Abstract
The light-scattering effect in the dye-sensitized solar cells (DSCs) was studied by controlling TiO2 phase composition and morphology by fabrication of double-layer cells with different arrangement modes. The starting material for preparation of TiO2 cells was synthesized by an aqueous sol-gel process. X-ray diffraction and field emission scanning electron microscopic analyses revealed that TiO2 nanoparticles had particle size ranging between 18 and 44 nm. The optical property and band gap energy of TiO2 nanoparticles were studied through UV-Vis absorption. The indirect optical band gap energy of anatase and rutile nanoparticles was found to be 3.47 and 3.41 eV, respectively. The...
Improvement in TiO2 photocatalytic performance by ZrO2 nanocompositing and immobilizing
, Article Desalination and Water Treatment ; Volume 57, Issue 58 , 2016 , Pages 28450-28459 ; 19443994 (ISSN) ; Sadrnezhaad, S. K ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
In this work, the effect of addition of ZrO2 to TiO2 and catalyst geometry on photocatalytic properties of the nanocomposite TiO2/ZrO2 was investigated. The traditional use of powdery photocatalyst for the degradation of organic compounds has post-treatment problems which means much higher time and costs. A novel method to minimize these problems is immobilization by insertion onto an inert substrate. Several geometries of TiO2–10%ZrO2 (T-10Z) nano-photocatalysts (powder, fiber, film, and network-shaped) were produced using different templates. The products were characterized by X-ray diffraction, field emission scanning electron microscopy, Brunauer–Emmett–Teller, and diffuse reflectance...
Functionalized copper oxide–zinc oxide nanocomposite: synthesis and genetic programming model of dye adsorption
, Article Desalination and Water Treatment ; Volume 57, Issue 40 , 2016 , Pages 18755-18769 ; 19443994 (ISSN) ; Chamani, H ; Kariminia, H. R ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
The functionalized copper oxide–zinc oxide nanocomposite (FCZN) was synthesized and characterized using Fourier transform infrared, scanning electron microscopy, X-ray diffraction, X-ray fluorescence, and BET. Dye removal from aqueous solution was done in a batch system using FCZN as an adsorbent. The effects of adsorbent dosage, initial dye concentration, pH, temperature, and additive salts on dye removal were investigated. Isotherms, kinetics, and thermodynamics of dye adsorption were studied. Equilibrium and kinetic data were fitted by Langmuir isotherm and pseudo-second-order kinetic, respectively. The thermodynamic data showed that dye adsorption was spontaneous, endothermic, and...
Porous Carrageenan-g-polyacrylamide/bentonite superabsorbent composites: swelling and dye adsorption behavior
, Article Journal of Polymer Research ; Volume 23, Issue 3 , 2016 , Pages 1-10 ; 10229760 (ISSN) ; Bassampour, Z ; Ghasemzadeh, H ; Nazari, M ; Zolghadr, L ; Hosseini, S. H ; Sharif University of Technology
Springer Netherlands
2016
Abstract
A novel superabsorbent composite based on kappa-Carrageenan (κC) was prepared by graft copolymerization of acrylamide (AAm) onto κC in the presence of bentonite powder using methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and sodium carbonate as a pore-forming agent. The swelling behavior in distilled water and in solutions with different pH values was investigated. The results indicated that with increasing carrageenan/bentonite weight ratio, the swelling capacity is increased but the gel content is decreased. The swelling rate of the hydrogels was improved by introducing sodium carbonate as pore-forming agent. The prepared superadsorbent...
Comparison of adsorption process by GAC with novel formulation of coagulation - Flocculation for color removal of textile wastewater
, Article International Journal of Environmental Research ; Volume 2, Issue 3 , 2008 , Pages 239-248 ; 17356865 (ISSN) ; Seif, S ; Javid, A. H ; Borghei, M ; Sharif University of Technology
2008
Abstract
This study evaluates the effectiveness of adsorption process by Granular Activated Carbon (GAC) compared with a novel formulation of coagulation - flocculation process for dye removal from textile wastewater. In this regard, acidic, reactive, disperse and direct red dye are used to prepare the synthetic dye. Dominant wave length for each dye is determined by spectrophotometeric method. Using GAC as adsorbent, equilibrium time and adsorption isotherm of each dye are determined with aid of spectrophotometric method. The results show that GAC can not remove dispersed red dye. Acidic red, direct red and reactive red of 5 mg/L concentration are removed by GAC up to %90, %88 and %43 in 30, 60 and...
Adsorption and oxidation of dye and tetracycline over hydrothermally synthesized polyresorcinol – Ferrite nanoparticles
, Article Desalination and Water Treatment ; Volume 212 , 2021 , Pages 376-389 ; 19443994 (ISSN) ; Alijani, H ; Hossein Beyki, M ; Jafari Pirouz, M ; Sharif University of Technology
Desalination Publications
2021
Abstract
This study focuses on developing an efficient material that integrates high adsorption performances of dye and antibiotics as well as effective oxidation activity of it. Herein, we report a facile method to synthesize polyresorcinol@CoFe2 O4 via a one-step hydrothermally route. The prepared composite possesses multifunctional performance for methylene blue (MB) and tetracycline (TC) removal with appropriate magnetic separation operation and significant removal ability with an adsorption capacity of 51.48 and 28.16 mg g–1, respectively. Meanwhile, the aforementioned composite exhibits a high oxidation activity toward MB and TC molecules where the adsorption capacity increases to 1,723 and 120...
Improved adsorption performance of ZIF-8 towards methylene blue dye by hybridization with nanodiamond
, Article Journal of Water Process Engineering ; Volume 50 , 2022 ; 22147144 (ISSN) ; Mohammadi, A ; Jafarpour, E ; Shojaei, A ; Moghaddam, A. L ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
A series of ZIF-8/OND hybrid nanostructures with different percentages of oxidized nanodiamond (OND) was prepared. Then, the adsorptive removal performance of pristine ZIF-8 and its nanohybrids with OND towards methylene blue (MB) was investigated. The fabricated adsorbents were characterized via thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption, field emission scanning electron microscopy and zeta potential measurements. The maximal adsorption capacity of ZIF-8 (242 mg/g) was found to grow steadily with the increment in OND content and reached an approximate plateau at 343 mg/g for the nanohybrid containing 5 wt% OND, i.e....
ZIF-8/Chitosan hybrid nanoparticles with tunable morphologies as superior adsorbents towards both anionic and cationic dyes for a broad range of acidic and basic environments
, Article Microporous and Mesoporous Materials ; Volume 343 , 2022 ; 13871811 (ISSN) ; Shojaei, A ; Hamzehlouyan, T ; Sharif University of Technology
Elsevier B.V
2022
Abstract
A series of nanohybrids using ZIF-8 in the presence of chitosan (CS) at various compositions (0.5–15 wt%) were synthesized. Thorough characterization exhibited that the morphology of the nanoparticles in terms of surface charge, particle size, specific surface area, and pore volume is significantly dominated by the CS content in the hybrid nanoparticles. Amongst the nanoparticles synthesized, a hybrid nanoparticle containing 2 wt% CS, named CS-ZIF-2, represented the largest positive zeta potential and smallest particle size. Moreover, adsorption experiments indicated that CS-ZIF-2 had considerable adsorption capacity against anionic dye (Congo Red, CR) compared with the individual ZIF-8 and...