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    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) Koohestani, H ; 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... 

    Superparamagnetic enzyme-graphene oxide magnetic nanocomposite as an environmentally friendly biocatalyst: Synthesis and biodegradation of dye using response surface methodology

    , Article Microchemical Journal ; Volume 145 , 2019 , Pages 547-558 ; 0026265X (ISSN) Kashefi, S ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
    Elsevier Inc  2019
    Abstract
    The unique properties of graphene oxide (GO) nanosheets were integrated with the superparamagnetic characteristics of the CuFe2O4 nanoparticles to synthesize the magnetic graphene oxide (MGO), which was chemically modified with 3-amino propyl trimethoxy silane (APTMS) to functionalize the amine group on MGO (MGO-NH2). Afterward, MGO-NH2 was activated with glutaraldehyde (GLU) as a crosslinking agent to synthesize the functionalized MGO (fMGO) and its capability toward covalent Laccase immobilization was investigated. The comprehensive structural analysis using various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating... 

    Reduction of Organic Dyes in Water Using MOFS and Their Composites

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Alireza (Author) ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samahe (Co-Supervisor) ; Khorasheh, Farhad (Co-Supervisor)
    Abstract
    A triple photocatalytic composite of biochar, metal-organic framework and phosphomolybdic acid was prepared through solvothermal treatment of iron (III) chloride hexahydrate, terephthalic acid, lavandulifolia-derived biochar and phosphomolybdic acid. The composite was thoroughly characterized and utilized for photodegradation of organic dyes under visible light irradiation. Investigations of reaction variables confirmed that, the highest yield of 96.2% for a cationic Rhodamine-B (RhB) dye was achieved at ambient temperature when using 0.07 g of catalyst at pH of 7 and a dye concentration of 10 ppm. The activity of the composite was superior compared to its individual components implying... 

    Synthesis and Characterization of Electrospun N/S Doped ZnO and Investigation of their Applications in Dye Degradation

    , M.Sc. Thesis Sharif University of Technology Shirvani Shiri, Tayyebe (Author) ; Poujavadi, Ali (Supervisor)
    Abstract
    In this research, the synthesis of the electrospum nano fiber doped zinc oxide and its photocatalyst usage was investigated. The band gap of the zinc oxide in the area of UV leads to deactivation of this material at the visible light. With due the attention to sunny weather in Iran and the fact that about 50 percentage of sunlight is visible light, producing and usage of catalyst materials actived at visible light is economical. Doping is one of the ways of activating ZnO at visible light, so in this research thiourea is used as the source of ZnO doping. The results of the expriments done at visible light and also spectrums of DRS, XPS and XRD prove that the doping is happened. Also, in this... 

    Organic Pollutants Degradation in Wastewater by Ultraviolet Irradiation Process Using Nano-structured Catalyst in a Batch Reactor

    , M.Sc. Thesis Sharif University of Technology Ahmadi, Shahin (Author) ; Kazemeini, Mohammad (Supervisor) ; Mahmoodi, Niyaz Mohammad (Supervisor) ; Baghalha, Morteza (Supervisor)
    Abstract
    Environmental issues and lack of drinking water had forced researchers to find some alternatives in order to wastewater treatment. Since dyes are used in a variety of industrial application such as textile, pharmaceutical, etc.; therefore, wastewater of these factories makes several environmental problems. Using catalysis under UV- irradiation (photocatalysis) is one of the cases that is used in wastewater treatment which the catalyst stimulated under UV- irradiation and this process degraded dyes. In this work, reactive red 198 degradation is investigated with MIL-53(Fe) and MIL-100(Fe) and in the literature section, the methods that was implemented by other researchers is studied.... 

    Photocatalytic Treatment of Azo based Textile Pollutants by Modified Bismuth Vanadate

    , M.Sc. Thesis Sharif University of Technology Hekmat, Amir (Author) ; 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... 

    Improving Photocatalytic Activity by Preparation of Magnetically Separable N-doped rGO/NiFe2O4@Ti-doped ZnOTernary Nanocomposite

    , M.Sc. Thesis Sharif University of Technology Abdi, Zahra (Author) ; Nemati, Ali (Supervisor) ; Khachatourian, Adrine Malek (Supervisor)
    Abstract
    The N-doped rGO/NiFe2O4@Ti-doped ZnO as a novel ternary nanocomposite with magnetic recyclable was obtained by a facile and low-cost hydrothermal method. The structure, morphology, and optical as well as magnetic properties of synthesized nanocomposite were analyzed using the X-ray diffraction (XRD), Fourier-transform infrared spectra (FTIR), Raman spectroscopy, Emission scanning electron microscopy (FESEM) with Energy dispersive spectra, Transmission electron microscopy (TEM), UV-vis diffusive reflectance spectra, and Vibrating sample magnetometer (VSM). The photocatalytic activity was determined by the degradation of Methylene blue (MB) and Methylene orange (MO) dyes under visible light... 

    Photocatalytic Dye Degradation of Wastewater Using Copper Composite Nanophotocatalyst by Advanced Oxidation Process

    , M.Sc. Thesis Sharif University of Technology Rezaei, Pardis (Author) ; Ghotbi, Cyrus (Supervisor) ; Mahmoodi, Niyaz Mohammad (Supervisor) ; Kazemeyni, Mohammad (Supervisor)
    Abstract
    Azo dyes that are the most common dyes in textile industries, are toxic and stable complex compounds. Release of this dyes in environment disturb the ecosystem and endanger human health. So selection of an appropriate method for treatment of them is a sensitive work. photocatalytic degradation is one of the best promising methods because of its perfect mineralization, middle condition and lack of creating the secondary pollutant. In this research CuO/CNT nanocomposite was synthesized and used as a photocatalyst. The surface features of CuO/CNT were surveyed by using Fourier transform infrared(FTIR), X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Photocatalytic efficiency of... 

    Copper oxide-carbon nanotube (CuO/CNT) nanocomposite: Synthesis and photocatalytic dye degradation from colored textile wastewater

    , Article Fibers and Polymers ; Volume 17, Issue 11 , 2016 , Pages 1842-1848 ; 12299197 (ISSN) Mohammad Mahmoodi, N ; Rezaei, P ; Ghotbei, C ; Kazemeini, M ; Sharif University of Technology
    Korean Fiber Society  2016
    Abstract
    In this paper, CuO/CNT nanocomposite was synthesized and its photocatalytic dye degradation ability for colored textile wastewater was studied. The characteristics of the nanocomposite were investigated by XRD, SEM and FTIR. The photodegradation of Direct Red 31 (DR31) and Reactive Red 120 (RR120) by CuO/CNT in presence of H2O2 was investigated. Photocatalytic dye degradation was determined by UV-vis spectrophotometer. Effects of catalyst dosage, initial dye concentration and salt on photodegradation performance were studied. The photocatalytic dye degradation ability of pure CuO and CuO/CNT nanocomposite is 78 % and 89 % for DR31 and 70 % and 87 % for RR120, respectively. The results showed... 

    Metal-organic framework (MIL-100 (Fe)): synthesis, detailed photocatalytic dye degradation ability in colored textile wastewater and recycling

    , Article Materials Research Bulletin ; Volume 100 , April , 2018 , Pages 357-366 ; 00255408 (ISSN) Mahmoodi, N. M ; Abdi, J ; Oveisi, M ; Alinia Asli, M ; Vossoughi, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this paper, three metal-organic frameworks (Materials of Institut Lavoisier: MILs-100 (Fe)) as porous nanomaterials were synthesized using FeCl3, Fe(NO3)3 and Fe2(SO4)3 and denoted as MIL-100-1, MIL-100-2 and MIL-100-3, respectively. The synthesized MILs-100 (Fe) were characterized by FTIR, SEM, TEM, XRD, UV–vis DRS and zeta potential. Basic Blue 41 (BB41) was used as a model dye to study the photocatalytic dye degradation ability of the synthesized metal organic frameworks. The results showed that the synthesized nanomaterials decolorized BB41. The decolorization kinetics followed first-order kinetic model. The rate constant was 0.0034, 0.0041, 0.0091 and 0.0289 (1/min) for 0.01, 0.02,... 

    A study of the DR23 dye photocatalytic degradation utilizing a magnetic hybrid nanocomposite of MIL-53(Fe)/CoFe2O4: Facile synthesis and kinetic investigations

    , Article Journal of Molecular Liquids ; Volume 301 , 2020 Bagherzadeh, S. B ; Kazemeini, M ; Mahmoodi, N. M ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this research, cobalt ferrite (CoFe2O4) magnetic nanoparticles as well as MIL-53(Fe) structure were synthesized by the hydrothermal and solvothermal methods, respectively. Moreover, magnetic composites of MIL-53(Fe)/CoFe2O4 nanoparticles with different cobalt ferrite loadings (i.e.; 0.05, 0.1 and 0.2 g) were prepared via the solvothermal method. The main novelty of the present research was to synthesize a magnetic composite of MIL-53(Fe)/CoFe2O4 nanoparticles in order to perform rapid photodegradation of Direct Red 23 (DR23) dye under the LED visible light irradiation. Good magnetic properties of the fabricated composite led to easy separation and rapid retrieval of the catalyst from the... 

    Degradation of Model Textile Dyes in Wastewater using Visible-Light Active Photocatalysts

    , M.Sc. Thesis Sharif University of Technology Heidarpour Chakoli, Hamed (Author) ; Soltanieh, Mohammad (Supervisor) ; Vossoughi, Manouchehr (Co-Supervisor) ; Padervand, Mohsen (Co-Supervisor)
    Abstract
    Textile dyes are a major category of organic pollutants and release of them in the environment causes serious problems. Among the most commonly used methods for colored wastewater, advanced oxidation processes, especially the photocatalytic process, are rapidly developing as a new and effective solution. However, there is still a need for high-level photocatalytic activity and improvement of this process to increase removal efficiency. In this study, we have tried to provide a higher performance for color removal using carbon nitride photocatalyst. Accordingly, two approaches have been proposed to improve the removal of rhodamine b, as one of the common dyes in the textile industries. The... 

    Degradation of Organic Pollutants in Water by Advanced Oxidation Process Using MIL-based Nanostructured Catalyst

    , M.Sc. Thesis Sharif University of Technology Kamandi, Ramtin (Author) ; Kazemini, Mohammad (Supervisor) ; Mahmoodi, Nyaz Mohammad (Supervisor)
    Abstract
    Octahedral crystals of Fe-Metal-organic frameworks like Fe-MIL-101, which is the most stable and active metal-organic frameworks; in combination with graphitic carbon nitride nanosheets could significantly enhance the photocatalytic activity of g-C3N4 for inorganic dye degradation under the irradiation of visible light application. This appropriate cocatalyst modifies the performance of semiconductor via suppressing the recombination of photo-induced carriers and since the synthesized composite prepared by in-situ procedure possesses close contact between each other, the migration of electrons in the photocatalytic reaction will be continued, so the degradation process via the active species... 

    Degradation of Dye in Wastewater Using iron Based Porous Nanocatalyst in a Batch Reactor

    , M.Sc. Thesis Sharif University of Technology Mehdipour, Mohammad Hossein (Author) ; Ghotbi, Cyrus (Supervisor) ; Mahmoudi, Niaz Mohammad (Supervisor)
    Abstract
    consumption of which (especially azo dyes) have been increasing nowadays, causing the increase of textile wastewaters. Usually, these wastewaters contain an immense number of dyes, and if these dyes release in the environment especially in waters, they cause some problems, such as the change of watercolor as well as taste, and affect creatures' lives severely. Moreover, If the dyes are left untreated in aquatic ecosystems, they can remain in the environment for a very long time, resulting in harmful and irreversible effects. Azo dyes are classified as mono, di-, three, azo dyes due to their bonds. Because dyes are increasingly used, nowadays, different methods are developed for the treatment... 

    Electrodeposited multi-walled carbon nanotubes on Ag-loaded TiO2 nanotubes/Ti plates as a new photocatalyst for dye degradation

    , Article RSC Advances ; Volume 5, Issue 56 , 2015 , Pages 44840-44846 ; 20462069 (ISSN) Mohaghegh, N ; Faraji, M ; Gobal, F ; Gholami, M. R ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    MWCNTs/Ag/TiO2NTs plates were synthesized via electrochemical reduction of functionalized multiwalled carbon nanotubes (MWCNTs) on Ag/TiO2NTs. The loading of silver nanoparticles was carried out by electroless reduction of Ag1+ onto TiO2 nanotubes previously formed by anodizing titanium. The SEM analysis revealed that MWCNTs were loaded significantly on the as-prepared Ag/TiO2NTs, where nanoparticles of Ag had grown on the walls of TiO2NTs. The photocatalytic activity of the synthesized plates was evaluated by the photodegradation of Methyl Orange (MO) dye under UV light irradiation. The results indicated that the MWCNTs/Ag/TiO2NTs demonstrated improved efficiency for MO photodegradation in... 

    Integrated system of multiple batches to evaluate the continuous performance of microbial cells in decolourization processes

    , Article Journal of Environmental Chemical Engineering ; Volume 6, Issue 1 , February , 2018 , Pages 728-735 ; 22133437 (ISSN) Vatandoostarani, S ; Bagheri Lotfabad, T ; Heidarinasab, A ; Ebadipour, N ; Yaghmaei, S ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Azo dye degradation in wastewater treatment is a subject which has garnered the attention of many research studies. In this study, an innovative approach, namely, an integrated system of five batches (ISFB), was developed to investigate the capability of Saccharomyces cerevisiae ATCC 9763 for continuous degradation of methyl red as a representative azo dye. Toward this end, an expanded immobilized microbial bed (EIMB) reactor was established with a bed of encapsulated yeast cells in sodium alginate. EIMB reactor was run in two modes, single batch and ISFB. Moreover, durability of the microbial cells was evaluated by repeating the continuous decolourization eight sequential times in EIMB at... 

    Kinetics Investigation of the Degradation of Environmental Pollutants by Electro-Fenton Processes Using Iron Vanadate Nanoparticles

    , M.Sc. Thesis Sharif University of Technology Maghbool, Roghaye (Author) ; Rahman Setayesh, Shahrbanoo (Supervisor)
    Abstract
    Nanocomposite FeVO4/CeO2 was synthesized by hydrothermal method and was applied for removal of methyl orange. This nanocomposite was characterized by SEM, FT-IR, XRD, BET methods. SEM images showed that FeVO4 nanorode decorated on CeO2 spherical particles. The results of XRD patterns confirmed the triclinic structure for Fe(III)vanadate and the cubic fluorite structure for cerium oxide. The surface area of FeVO4, CeO2 and FeVO4/CeO2 was determined by BET analysis which the results represented an increase in surface area in nanocomposite using cerium oxide as support. The electro-Fenton reaction was performed in undivided electrochemical reactor using stainless steel electrodes and the... 

    Photocatalytic Dyes Degradation in Wastewater Using Carbon Nanotube Based Composite Catalyst

    , M.Sc. Thesis Sharif University of Technology Shokrgozar, Atefeh (Author) ; Khorashe, Farhad (Supervisor) ; Baghalha, Morteza (Supervisor) ; Niyaz Mahmoodi, Mohammad (Supervisor)
    Abstract
    Increased photo catalytic activity of NiO and 〖Co〗_3 O_4 were obtained by Ni〖Co〗_2 O_4 synthesizing and supporting functionalized multiwall carbon nano-tubes via calcinations followed by hydrothermal precipitation. NiO, 〖Co〗_3 O_4 and Ni〖Co〗_2 O_4 were prepared in the same procedure exactly for the subsequent photo catalytic activity to be compared to Ni〖Co〗_2 O_4/MWCNT later on. The photo catalytic degradation of Reactive Red 120 dye as a deazo organic pollutant model was used for experimental photo catalytic performance analysis. The CCD method was applied for experimental designing, modeling, and optimizing the operational parameters of the photo catalytic degradation of RR120 using... 

    Photocatalytic activity of immobilized geometries of tio2

    , Article Journal of Materials Engineering and Performance ; Volume 24, Issue 7 , July , 2015 , Pages 2757-2763 ; 10599495 (ISSN) Koohestani, H ; Sadrnezhaad, S. K ; Sharif University of Technology
    Springer New York LLC  2015
    Abstract
    Photocatalysts that are used for waste water treatment are often suspended in the waste water during processing and then must be removed from the water after treatment. To reduce the post-degradation expenses and time, separation is facilitated by an immobilization process. The effect of immobilized TiO2 geometries on the photocatalytic behavior of the photocatalyst is investigated in this work. Powder, fiber, film, and network-shaped TiO2 nanocatalysts were produced by using different templates. The cellulose fiber and ceramic templates were used as substrates for fiber and film/network geometry production. The products were characterized by x-ray diffraction (XRD),... 

    Biological activated carbon process for biotransformation of azo dye Carmoisine by Klebsiella spp

    , Article Environmental Technology (United Kingdom) ; 2021 ; 09593330 (ISSN) Poorasadollah, D ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Mohseni, F. A ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    The feasibility of employing the biological activated carbon (BAC) process to debilitate azo dye Carmoisine by Klebsiella spp. was investigated. Plate assay revealed the capability of Klebsiella spp. for removal of Carmoisine via degradation. Kinetic parameters were measured for Carmoisine debilitation by Klebsiella spp. using the suspended anaerobic process. Two types of granular and rod-shaped activated carbon were used to form the biological beds in order to study the Carmoisine debilitation in batch processes. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to indicate the colonization and biofilm formation of bacteria grown on activated carbon...