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    Immobilized Manganese-porphyrin and Molybdenum-Schiff Base Complexes on Functionalized Magnetic Nanoparticles as Efficient Recyclable Nanocatalysts in Hydrocarbon and Sulfide Oxidation Reactions

    , Ph.D. Dissertation Sharif University of Technology Mortazavi Manesh, Anahita (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    In this thesis, functionalized Fe3O4 nanoparticles have been utilized as a support for immobilization of homogeneous catalysts. The catalytic activity of the supported heterogeneous nanocatalysts was investigated in hydrocarbon and sulfide oxidation reactions. In the first part of this research, imidazole functionalized Fe3O4 nanoparticles (Fe3O4@SiO2-Im) were used as a support to anchor manganese porphyrin complex, [MnT(4-OMeP)P]OAc; via axial ligation. Catalytic application of the immobilized manganese porphyrin was studied in oxidation of alkenes and sulfides. To find suitable reaction conditions, the effect of different parameters such as solvent and temperature on immobilization process... 

    Reduction of Sulfur Content of Model Feed by Oxidative Process in them Presence of Carbon Structures Based W-Mo Nanocatalysts

    , Ph.D. Dissertation Sharif University of Technology Hassannia, Saeed (Author) ; Kazemini, Mohammad (Supervisor) ; Rashidi, Alimorad (Supervisor) ; Hajjar, Zeinab (Co-Supervisor)
    Abstract
    In this research, molybdenum and tungsten catalysts modified with cobalt and nickel on a carbon support have been synthesized and investigated in the oxidation desulfurization process. A model fuel was used to evaluate the synthesized catalysts. This model fuel was n-decane. dibenzothiophene was also used as a sulfur model. The synthesized catalysts were subjected to various analyzes such as XRD, FTIR, Raman, BET-BJH, NH3-TPD, TEM and ICP-OES for structural evaluation. On the other hand, synthetic parameters such as metal loading rate, molar or weight ratio of secondary metal (cobalt and nickel) to primary metal (molybdenum and tungsten) and molar ratio of citric acid to primary metal as... 

    Fabrication of Magnetic Halloysite-Supported Catalyst for Reduction of Organic Dyes in Water

    , M.Sc. Thesis Sharif University of Technology Latifipour, Mostafa (Author) ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samaheh (Supervisor)
    Abstract
    A new magnetic catalytic nanocomposite of Hal-MT-Cys-Ag/MNCD was fabricated and utilized for catalyzing reductive de-colorization of methyl orange and rhodamin B in aqueous media at room temperature. To prepare this material, Cl-functionalized halloysite nanoclay was successively reacted with melamine and 2,4,6-trichloro-1,3,5-triazine to furnish multi-nitrogen containing ligand on halloysite surface. Then, magnetic carbon dots were crafted through a facile method and decorated with Ag nanoparticles and cysteine to furnish Cys-Ag/MNCD species. The final nanocomposite was obtained via incorporation of this latter species onto functionalized halloysite. This was characterized through the XRD,... 

    Reducing Sulfur Dioxide Using NANO-Structured Materials

    , M.Sc. Thesis Sharif University of Technology Fasahat, Hossein (Author) ; Safekordi, Ali Akbar (Supervisor)
    Abstract
    In this research, absorption and oxidation catalytic scenarios were examined using previous studies in the field of SO2 removal. Nanostructures zeolite 13X, 5A zeolite, gamma alumina and activated carbon were purchased, then structure, function and adsorption isotherm of each adsorbent were evaluated in 5 concentrations of 250, 500, 750, 1000 and 1250 ppm of contaminants. Final results showed that zeolite 13X compared to other Nano-adsorbents has higher ability to SO2 absorption, and thus the final tests such as temperature and pressure evaluation were performed on the selected sorbent. To further evaluation, the absorbent curves based on two models of BDST (Bed depth service time) and... 

    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... 

    Application of Magnetic Bi-and Trimetallic Nanocatalysts Based on Fe in the Synthesis of Polycyclic Heterocycles

    , M.Sc. Thesis Sharif University of Technology Mousazadeh Fazeli, Pegah (Author) ; Matloubi Moghaddam, Firooz (Supervisor) ; Sajjadi, Ali Akbar (Co-Advisor)
    Abstract
    Nowadays, two metallic catalyst are used in many organic reaction; so,different types of these catalytic systems have been synthesized up to now and been employed. One of these systems that recently has attracted many attention is magnetic two metallic nanocatalyst, that showing very good activity due to the synergistic effect between the two metal and fine particle size.On the other hand, poly cyclic heterocyclic compounds are one the main families of organic compounds having many application in biochemicals and pharmaceuticals. The main purpose of this project is to introduce a new method for the synthesize of these compounds such as tetrazoles and 1,4-dihydropyridines, using two- and... 

    Application of Cellulose Nanofibers Coated Quartz Crystal Microbalance (QCM) Biosensor for Amino Acid Detection in Aqueous Media

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Marzieh Sadat (Author) ; Irajizad, Azam (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
    Abstract
    Developing a simple, cost effective and accurate detection method for L-lysine (Lys), L-leucine (Leu) and glycine (Gly) as the important analytes in clinical diagnostics, biological processes and food industries is of great interest. Therefore, in the first part of this research, cellulose nanofibrils (CNFs) were coated on a quartz crystal microbalance (QCM) surface by spin coating to achieve a QCM biodetector for Gly. Thus, the two-layer CNFs coating was selected as sensing film and was applied for following experiments. In the next step, the coated QCMs were carefully characterized before and after interaction with Gly using water contact angle (WCA), Fourier transform infrared... 

    1, 3- Dipolar Cycloaddition Reactions of Azomethine Ylides of Ninhydrin with Chalcones and Investigation of Asymmetric Addition of TMSCN to Imines

    , M.Sc. Thesis Sharif University of Technology Assempour, Nazanin (Author) ; Saidi, Mohammad Reza (Supervisor) ; Jadidi, Khosrow (Supervisor) ; Mehrdad, Morteza (Co-Advisor)
    Abstract
    Part 1
    1,3-dipolar cycloaddition reactions offer convenient routes for the construction of a variety of five-membered heterocycles. This thesis represents a simple synthetic method via 1,3-dipolar cycloaddition reaction to prepare a novel class of spiro pyrrolidines and spiro pyrrolizidines which exhibit many biological activities. Non-stabilized azomethine ylides which generated in situ by the decarboxylative condensation of ninhydrin with proline and sarcosine were used as a 1,3-dipoles. On the other hand, chalcone and its derivatives with an impressive array of pharmacological activities were the dipolarophiles in these reactions. The reactions were carried out through reflax... 

    Modeling of Side Reactions in Propane Dehydrogenation Over Pt-Sn/γ-Al2O3 Catalyst

    , M.Sc. Thesis Sharif University of Technology Farjoo, Afrooz (Author) ; Khorasheh, Farhad (Supervisor)
    Abstract
    The kinetics of side reactions in dehydrogenation of propane over a supported platinum catalyst modified by tin was investigated. Catalytic dehydrogenation over a commercial Pt-Sn/γ-Al2O3 was carried out in a laboratory-scale plug-flow reactor at 580 to 620oC under atmospheric pressure. Several kinetic models derived from different reaction mechanisms were tested using experimental data obtained over a range of reaction conditions. It was found that the kinetics of the main dehydrogenation reaction was best described in terms of a Langmuir-Hinshelwood mechanism where adsorption of propane was the rate controlling step. Simple power low rate expressions were used to express the kinetics of... 

    Modified Zeolitic Nanostructures: Synthesis, Characterization and the Investigation of Their Catalytic-Sorption-Antibacterial Applications

    , Ph.D. Dissertation Sharif University of Technology Padervand, Mohsen (Author) ; Gholami, Mohammad Reza (Supervisor) ; Gobal, Fereydoun (Co-Advisor)
    Abstract
    Modified zeolitic nanostructures were prepared by sol-gel, hydrothermal and coprecipitation methods. At first step, natural zeolite was used as a support for preparing the Ag/AgBr/TiO2 photocatalysts. Their photocatalytic properties were studied by degradation of pollutants and microorganism inactivation at the presence of different illumination source. These processes were mechanistically investigated and the results were explained. At second step, mordenite anocrystals, which synthesized by hydrothermal method, were used as an effective support to prepare the AgX/TiO2/MOR photocatalysts. Photocatalytic degradation of an azo dye performed over these nanocomposites and a mechanism suggested... 

    Kinetics Study and Determining an Optimum Reactor Condition for Dimethyl-ether Synthesis by Dehydration of Methanol over Nano-Crystalline γ-Al2O3

    , M.Sc. Thesis Sharif University of Technology Alamolhoda, Sarah (Author) ; Kazemeini , Mohammad (Supervisor) ; Khorashe, Farhad (Supervisor) ; Khandan, Nahid (Supervisor)
    Abstract
    Dimethyl Ether (DME) is a pure and economic fuel which can be used as a suitable alternative for diesel fuels. Two processes are traditionally used for DME synthesis: producing methanol from synthesis gas and then dehydrating it to DME (direct process), and converting methanol into DME in a catalytic dehydration reactor over a solid-acid catalyst (indirect process), in which the indirect process seems to have economical advantage. In this research, the γ-Al2O3 catalyst was synthesized through precipitation process and then characterized by powder X-ray diffraction (XRD) and porosimetry analysis. Afterwards this catalyst was utilized in methanol dehydration reaction in a slurry reactor. Next,... 

    Kinetic Study of Heterogeneous and Homogeneous Catalytic Reactions in Molecular and Ionic Solvents and Their Mixtures

    , Ph.D. Dissertation Sharif University of Technology Khodadadi Moghaddam, Mohammad (Author) ; Gholami, Mohammad Reza (Supervisor) ; Habibi Yangjeh, Aziz (Supervisor)
    Abstract
    Solvatochromic parameters (ETN: normalized polarity parameter, π*: dipolarity/polarizability, β: hydrogen-bond acceptor basicity, α: hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (2-hydroxyethylammonium formate) at 25 ◦C. The applicability of nearly ideal combined binary solvent/Redlich-Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. Solute-solvent and solvent-solvent interactions were applied to interpret the results. Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/Al2O3, was carried out in... 

    Experimental Investigation of a Monopropellant Thruster Using Hydrogen Peroxide

    , M.Sc. Thesis Sharif University of Technology Nikfar, Rouzbeh (Author) ; Farahani, Mohammad (Supervisor)
    Abstract
    Monopropellant thrusters are one of the most common types of propulsion systems that are used extensively in space applications. Especially thrusters with a capacity of less than 50N, they are used on space satellites and are developing rapidly. Problems such as contamination, toxicity of the propellant, difficulty in storing and custody, as well as price, led to the removal of the hydrazine from the focus of attention and focus on green propulsion. One of these, is the green propellant of hydrogen peroxide, which is decomposed in the proper catalytic vicinity, and the only chemical decomposition products are oxygen and water vapour. The present study aims to design and construct mono... 

    Experimental Study of Formaldehyde Decomposition Using a Plasma - Catalyst Hybrid Reactor as a Potential Voc Removal Technique

    , M.Sc. Thesis Sharif University of Technology Nemati Tamar, Amin (Author) ; Hamzeh Louyan, Tayyebeh (Supervisor) ; Khani, Mohammad Reza (Supervisor)
    Abstract
    Volatile organic compounds (VOCs) has harmful environmental and health effects and appropriate processes are needed to remove them from industrial and indoor environments. In this study, formaldehyde as one of the most toxic VOCs was investigated. Various methods have been developed to remove formaldehyde, however due to the to their low removal efficiencies, secondary pollution, and low energy efficiency, development of alternative methods will be beneficial. In recent years, the use of a combination of non-thermal plasma and catalyst technologies, called plasma-catalytic hybrid reactors, has provided significant results in the fields of chemical synthesis and removal of pollutants. In the... 

    Experimental Study of the Aging Effect on the Oxidation Catalyst Performance as an Emission Control Device for 4-stroke Gasoline Carburetor Motorcycles

    , M.Sc. Thesis Sharif University of Technology Taheri, Arman (Author) ; Hamzehlouyan, Tayebeh (Supervisor)
    Abstract
    There are more than one million motorcycles in the city of Tehran that are responsible for significant amounts of various air pollutants emissions such as carbon monoxide and hydrocarbons. Oxidation catalysis, as the exhaust aftertreatment system of motorcycles, can reduce the emission of CO and hydrocarbon pollutants. The efficiency of these catalysts under typical operating conditions of vehicle exhaust gas has been studied in the literature. However, due to the specific features of motorcycles exhaust gas in Tehran, such as ultra-rich combustion, low air to fuel ratio (lambdas as low as 0.6-0.7), different exhaust gas composition and significant amount of lubricating oil consumption,... 

    Experimental Investigation and Modeling of Ferrous Biooxidation in a Monolithic Bioreactor

    , Ph.D. Dissertation Sharif University of Technology Kahrizi, Ehsan (Author) ; Vossoughi, Manoochehr (Supervisor) ; Alemzadeh, Iran (Supervisor)
    Abstract
    The bio-oxidation of ferrous iron is a potential industrial process in the regeneration of ferric iron and the removal of H2S in combustible gases. Bio-oxidation of ferrous iron may be an alternative method of producing ferric sulfate, which is a reagent used for removal of H2S from biogas, tail gas and pulp and paper industry. For practical use of this process, this study evaluated the optimal pH and initial ferric concentration. pH control looks like a key factor as it acts both on growth rate and on solubility of materials in the system. Some process variables such as pH and amount of initial ferrous ions on oxidation by A. ferrooxidans and the effects of such process variables dilution... 

    Experimental Investigation for Enhancing the Lifetime of Co,Ru/La(γ-Al2O3) Catalyst in Fischer Tropsch Synthesis

    , Ph.D. Dissertation Sharif University of Technology Hemmati Mahmoudi, Mohammad Reza (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor) ; Zarkesh, Jamshid (Co-Advisor)
    Abstract
    Fischer-Tropsch synthesis (FTS) is the main part of a Gas to Liquid (GTL) process. In this reaction which shall be done based upon iron or cobalt catalysts, H2 and CO molecules (namely Syngas) transform to long hydrocarbon chains. Regarding all of the advantages of cobalt catalysts in comparison with iron counterparts, Research Institute of Petroleum Industry (RIPI) began investigations since two decade ago. The present catalyst comprised of cobalt as active metal, ruthenium as activity promiter and lanthanum as support (gamma alumina) modifier. By the way, still some areas such as its lifetime duration and deactivation needs to be improved by complimentary researches. The present... 

    Characterization of V2O5 Spent Catalyst & Feasibility Study of its Regeneration

    , M.Sc. Thesis Sharif University of Technology Soltani Nejad, Mohammad (Author) ; Sadrnezhaad, Khatiboleslam (Supervisor) ; Farzami, Faezeh ($item.subfieldsMap.e)
    Abstract
    In this study, at first the V2O5 spent catalysts were characterized. The aim was to identifying whether these catalyst may be regenerated. Then, for feasibility study of them, three methods were applied: washing, diffusion and milling the spent catalysts for their subsequent reproduction. A variety of techniques such as XRD, XRF, AAS, TPR and TPO were applied in order to identify factors contributing in vanadium pentoxide catalysts deactivation. The results showed that approximately all of pollutants caused their performance deterioration, while they still have some active phases. Then, the polluted catalysts were washed (their yield increased from 43% to 72.2%). In the underside of the... 

    Stabilization of 2-(4-phenyl-1H-1,2,3-triazol-1-yl) on the Magnetic Nano Particle Fe3O4 as Suitable Ligand for Stabilization of Cu (II) and Use It in the Huisgen's Reaction & The Readuction of Nitro Compounds in the Presence of Gold Nanoparticles Immobilized on Magnetic Nanoparticle Fe3O4 Functionalized with Ionic Liquid

    , M.Sc. Thesis Sharif University of Technology Firouzi, Hamid Reza (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    A novel magnetic heterogeneous copper catalyst was synthesized by immobilization ofcopper ion onto the triazole functionalized Fe3O4. The catalyst was fully characterized by FTIR, TGA, CHN, SEM, TEM, EDX and atomic adsorption spectroscopy. The resulting catalystwas used in the synthesis of 1,2,3-triazoles via one-pot three component reaction of alkynes,alkyl halides, sodium azides under green condition. The catalyst was reused for ten times andno significant loss of activity was observed. Supported gold (III) on poly(ionic liquid) coated on magnetic nanoparticles produced a highly active, stablerecoverable and high loading for the synthesis of propargylamines (A3 coupling reaction) under... 

    Modeling Reaction and Distribution of Water in Nanopores of the Cathode Catalyst Layer of PEM Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Nushak, Fatemeh (Author) ; baghalha, morteza (Supervisor)
    Abstract
    In the proton exchange membrane fuel cells (PEM, the produced water would be divided into two phases of vapor and liquid. distribution of both liquid and vapor phases in different cell layers affects the performance, the efficiency and the life of a fuel cell significantly. Moreover, Nano pores of the cathode catalyst layer are involved with some phenomena such as electrochemical reaction kinetics, heat and mass transfer and interface phase change. One of the most important problems in the performance of fuel cells is distribution of liquid water in the porous areas. Water flooding in fuel cells causes to delay in oxygen transport to active sites in the catalyst layer because the pores of...