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    Design and Synthesis of Heterogeneous Nanocatalysts based Metals and their Application in Organic Reactions

    , M.Sc. Thesis Sharif University of Technology Azaryan, Reza (Author) ;
    Abstract
    Ferrite spinels are very valuable as heterogeneous catalysts and have the ability to separate. In this dissertation, ferrite nanoparticles were synthesized by co-precipitation method and used in carbon-phosphorus and phosphorus-sulfur bond formation reactions. The structure of these compounds was investigated by different techniques. The ferromagnetic CuFe2O4 ferrite catalyst was expanded in the C-P bond formation reaction, resulting in a convenient and efficient method. Phosphorylation of alkenes was performed using a model reactant, dialkyl phosphite as a source of phosphorous compounds, and beta-ketophosphosphonates were synthesized. Beta-ketophosphonates are important intermediates for... 

    Design and Synthesis of Heterogeneous Nanocatalysts Based on Immobilized Metals on Polymeric Substrates and their Applications in Organic Reactions

    , Ph.D. Dissertation Sharif University of Technology Motamedi, Anahita (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Today, catalysts have shown the growing applications in chemical industries especially for drug synthesis. Using immobilized heterogeneous catalysts is a sensible way to benefit from advantages of both heterogeneous and homogeneous catalysts. In this regards, homogeneous catalysts are immobilized on to a solid support through various methods. However, low loading amount of homogenous part and subsequently insufficient catalytic activity are main limitations of immobilized heterogeneous catalysts. For this reason, polymeric supports have been introduced to immobilize metal ions or nanoparticles. These polymeric supports not only possess advantages such as anti-corrosive properties, simple... 

    Preparation of a Monolithic Nanocatalyst Utilizing Carbon Nanotubes for HDS Process

    , M.Sc. Thesis Sharif University of Technology Soghrati, Elmira (Author) ; Kazemeini, Mohammad (Supervisor) ; Rashidi, Alimorad (Supervisor)
    Abstract
    Monolithic nanocatalysts for naphta hydrodesulfurization process have been prepared and evaluated. Commercial cordierite monolith was used as a ceramic substrate. Initially, the monoliths were pretreated with nitric acid solution in order to increase specific surface area. After that, carbon nanotubes were grown through catalytic decomposition of methane over prepared monoliths. Finally, the CNT-coated monoliths were oxidized with ozone and an aqueous solution of H2O2. For the preparation of HDS Co-Mo nanocatalysts, the metal content of aqueous solution including cobalt nitrate, ammonium heptamolybdate were then impregnated onto the prepared supports. Next, samples of prepared supports and... 

    Production of Vegetable Oil Biodiesel by Heterogeneous Catalytic Trans-Esterification Method in Micro-Reactor

    , M.Sc. Thesis Sharif University of Technology Piran, Samira (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Ali Asghar (Supervisor)
    Abstract
    The purpose of this study is to study heterogeneous nanocatalysts for the production of biofuels by the method of exchange of styrene using oil and methanol as a fossil fuel alternative. Preparation of nanocatalysts, performing characteristic tests and investigating the reaction in different operating conditions in the batch reactor has already been studied. Therefore, in this study, the production of biodiesel fuel using the trans-esterification of canola oil with nanocatalysts in the micro-reactor reactor will be discussed. Previously, a heterogeneous catalyst (lithium based on calcium-lanthanum) was constructed using a co-incineration method and a wet inoculum, and as active and stable... 

    Production of Biodiesel Using Eggshell as Catalyst

    , M.Sc. Thesis Sharif University of Technology Khatibi, Maryam (Author) ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
    Abstract
    The aim of this project is to investigate and synthesize CaO-based nanocatalysts derived from chicken eggshell calcination with alkali metals and sodium-potassium compounds promoters used in the transesterification reaction of canola oil and methanol. Sections of this thesis include the synthesis of nanocatalysts, catalyst characterization tests, and investigation of reaction under optimal conditions. Two groups of catalysts containing different weight percentages of alkali metals based on CaO and 1 %wt sodium-potassium based on CaO with different weight percentages of these two elements were synthesized by wet impregnation method and used in the reaction under optimum condition. Catalyst... 

    Production of Biodiesel from Vegetable Oils by Esterification Method Using Calcium Oxide as Base Catalyst

    , M.Sc. Thesis Sharif University of Technology Jalali Varnamkhasti, Roshanak (Author) ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
    Abstract
    The aim of this project is to fabricate and study heterogeneous CaO-based nanocatalysts with lithium and zinc enhancers for the esterification reaction of rapeseed oil and methanol to produce biodiesel as a renewable and alternative fuel for fossil fuels. Is. First, Zn-Li / CaO catalysts with weight ratio Li: Zn: CaO, 2: 2: 7 and by combining different percentages of Li100% promoter, Li75% -Zn25%, Li50% -Zn50%, Li25% -Zn75%, 100% Zn were made on the basis of CaO by wet inoculation. Characterization tests to evaluate the structure and characterization such as X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (EDX) spectroscopy, Bruner-Emmett-Teller... 

    Preparation of Cobalt and Manganese Salts of Para-amino Benzoic Acid Supported on Graphene Oxide as an Oxidative Nanocatalysts

    , M.Sc. Thesis Sharif University of Technology Nasiri Kalkhoran, Shahrokh (Author) ; Mahmoodi Hashemi, Mohammad (Supervisor)
    Abstract
    In this thesis, a heterogeneous nanocatalyst based on graphene oxide was synthesized. To improve the graphene oxide, it was reacted with paraaminobenzoic acid and then metal salts (cobalt and manganese) were coated on it. The structure of the catalyst was confirmed by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), quantitative X-ray diffraction (EDS) and infrared (FT-IR) spectroscopy. Finally, the catalytic properties of the catalysts were evaluated in the oxidation reaction of different alcohols in the presence of oxygen. In the presence of benzyl alcohols with lethal electron groups, the oxidation conditions are stricter and the reaction efficiency is lower.... 

    Design and Synthesis of Heterogeneous Nano Catalyst Based on Immobilized Palladium Metal on Double Network Hydrogel and Its Application in Organic Reactions

    , M.Sc. Thesis Sharif University of Technology Ghasemzadeh, Solmaz (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In the past few decades, many attempts have been made to combine the benefits of homogeneous and heterogeneous catalysts. The immobilization of homogeneous catalysts onto the surface of heterogeneous supports is the result of such efforts. In this research, immobilized heterogeneous catalysts were designed and synthesized based on double network hydrogels, which produce from interpenetrating of two biocompatible and biodegradable polymer networks. In order to provide magnetic responsibility and easy separation of catalyst from the reaction mixture, the magnetic nanoparticles were dispersed onto the surface of double network hydrogel. Finally, various metal nanoparticles such as palladium and... 

    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... 

    Experimental Investigation of Biodiesel Production from Oils by Transesterification Method Catalyzed by Nano-heterogeneous Catalysts

    , M.Sc. Thesis Sharif University of Technology Maleki, Hesam (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor)
    Abstract
    This study aims at synthesizing and investigating of heterogeneous catalysts for biodiesel production as an alternative to fossil fuel with the transesterification of oil and methanol. Three main sections of this thesis concern the synthesis of nano-catalysts, characterization analysis, and investigation of the transesterification reaction under different condition. Two series of heterogeneous catalysts, including different molar ratios of X%Li/Ca-La (X=0-7%) and Ca/Talc (Ca, 3Ca/1Talc, 1Ca/1Talc, 1Ca/3Talc, Talc) has been synthesized as active and stable catalysts to study the transesterification reaction of canola oil and methanol for biodiesel production. Prepared catalysts have been... 

    Two-stage thermocatalytic upgrading of fuel oil to olefins and fuels over a nanoporous hierarchical acidic catalyst

    , Article Petroleum Science and Technology ; Volume 37, Issue 16 , 2019 , Pages 1910-1916 ; 10916466 (ISSN) Ghashghaee, M ; Shirvani, S ; Ghambarian, M ; Eidi, A ; Sharif University of Technology
    Taylor and Francis Inc  2019
    Abstract
    A two-stage thermocatalytic upgrading process using a novel catalyst was investigated to produce light olefins and liquid fuels from fuel oil. The upgraded oil from the first thermal stage demonstrated lower viscosity and higher crackability compared to the virgin feedstock. In the next step, the vapor-phase catalytic cracking of the upgraded fraction was implemented over a novel nanoporous composite catalyst, characterized by the XRD, FTIR, NH3- TPD, and N2 physisorption techniques. In total, more than 55 wt% of light olefins, particularly propylene (25.5 wt%) together with 25.4 wt% and 32.5 wt% of gasoline and diesel fuel were obtained in this process. © 2019, © 2019 Taylor & Francis... 

    The oxidative desulfurization process performed upon a model fuel utilizing modified molybdenum based nanocatalysts: Experimental and density functional theory investigations under optimally prepared and operated conditions

    , Article Applied Surface Science ; Volume 527 , 2020 Hasannia, S ; Kazemeini, M ; Rashidi, A ; Seif, A ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    CoMo/reduced graphene oxide (rGO) catalyst was synthesized for the oxidative desulfurization process (ODS) of dibenzothiophene (DBT) in n-decane. Parameters including total metal (Co and Mo) loading, Co/Mo and CA (citric Acid)/Mo molar ratios were investigated toward achieving optimum conditions. The catalysts were characterized by the XRD, ICP, FTIR, Raman Spectroscopy, BET-BJH, NH3-TPD, XPS, and TEM methods. The product sulfur content was measured by the ICP-OES while the product was evaluated using FTIR and 1H NMR analyses. All experimental stages were designed using Design-Expert software. High BET area, acidity, uniform particle size, and Co-promoter played key roles in this... 

    The effect of temperature on the TCVD growth of CNTs from LPG over Pd nanoparticles prepared by laser ablation

    , Article Physica B: Condensed Matter ; Volume 405, Issue 16 , 2010 , Pages 3468-3474 ; 09214526 (ISSN) Pasha, M. A ; Poursalehi, R ; Vesaghi, M. A ; Shafiekhani, A ; Sharif University of Technology
    2010
    Abstract
    TCVD growth of multiwalled carbon nanotubes (MWCNTs) was reported by catalytic decomposition of liquefied petroleum gas (LPG) at a temperature range of 580800 °C. Laser ablation was employed as a simple and rapid technique to produce Pd nanoparticles which possess effective catalytic activities for CNT synthesis. UVvisible spectroscopy and TEM images confirmed that the Pd nanoparticles are stable for a long time and have rather spherical shape with average size of 7 nm. SEM and TEM observations and Raman spectroscopy demonstrated that the CNTs have a wavy structure, dense morphology and acceptable crystallinity. Since Pd nanoparticles are inactivated or agglomerated at extremes of the... 

    The effect of Pd addition to Fe as catalysts on growth of carbon nanotubes by TCVD method

    , Article Applied Surface Science ; Volume 254, Issue 20 , 15 August , 2008 , Pages 6416-6421 ; 01694332 (ISSN) Mortazavi, S. Z ; Reyhani, A ; Iraji zad, A ; Sharif University of Technology
    Elsevier  2008
    Abstract
    The effects of Pd addition to Fe (Pd/Fe = 0, 2.5/7.5, 5/5, 7.5/2.5 and 1) and growth temperatures (920 and 970 °C) on density, diameter and growth mode of carbon nanotubes (CNTs) have been studied. SEM observations and TG analyses confirmed that the CNT yields depend on Pd/Fe ratios as (7.5/2.5) > (5/5) > Pd > (2.5/7.5) > Fe at both growth temperatures. TEM data showed that addition of Pd results in tip growth mode. From Raman spectroscopy data, the order of samples' structural quality (I G /I D ratio) are Fe > Pd/Fe (2.5/7.5) > (5/5) > (7.5/2.5) > Pd and the I G /I D ratios increase by decreasing the growth temperature. Films with higher concentration of Fe (Pd/Fe = 0, 2.5/7.5) contain some... 

    Synthesis of highly dispersed nanosized NiO/MgO-Al2O3 catalyst for the production of synthetic natural gas with enhanced activity and resistance to coke formation

    , Article Industrial and Engineering Chemistry Research ; Volume 57, Issue 38 , 2018 , Pages 12700-12714 ; 08885885 (ISSN) Ebadi, A ; Tourani, S ; Khorasheh, F ; Sharif University of Technology
    Abstract
    Nickel nanoparticles supported on MgO-Al2O3 and Al2O3 were synthesized by an impregnation method using dinitrobisethylenediamine nickel and nickel nitrate hexahydrate as precursors and were used as catalysts for CO methanation. Different MgO contents (1.5-11.25 wt %) were employed for the preparation of supports, and NiO loadings were in the range of 10-40 wt %. The optimum catalyst prepared from proper amounts of MgO (∼2 wt %) and NiO loading (20 wt %) with [Ni(en)2(H2O)2](NO3)2 as precursor and a mesoporous support with a wide range of mesopores resulted in highly dispersed nickel nanoparticles that exhibited moderate metal-support interactions, lower acidic surface sites, and enhanced... 

    Synthesis and characterization of supportless Ni-Pd-CNT nanocatalyst for hydrogen production via steam reforming of methane

    , Article International Journal of Hydrogen Energy ; Volume 43, Issue 3 , 2018 , Pages 1319-1336 ; 03603199 (ISSN) Chaichi, A ; Sadrnezhaad, S. K ; Malekjafarian, M ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Supportless Ni-Pd-0.1CNT foamy nanocatalyst with specific surface area of 611.3 m2/g was produced by electroless deposition of nickel, palladium and multiwall carbon nanotube (MWCNT) on interim polyurethane substrate. Application of temperature programmed reduction (TPR) and temperature programmed oxidation (TPO) data into Kissinger (Redhead) kinetic model showed lessening of their activation energies due to Pd and CNT addition. Presence of foamy Ni/SiC caused 8% higher steam reforming of methane; while Ni-Pd-0.1CNT presence resulted in 22% higher methane conversion. The catalytic behavior of the samples was described by morphological and compositional studies which were carried out by... 

    Synthesis and characterization of molybdenum (VI) complex immobilized on polymeric Schiff base-coated magnetic nanoparticles as an efficient and retrievable nanocatalyst in olefin epoxidation reactions

    , Article Applied Organometallic Chemistry ; Volume 34, Issue 3 , 2020 Mortazavi Manesh, A ; Bagherzadeh, M ; Sharif University of Technology
    John Wiley and Sons Ltd  2020
    Abstract
    In this study, a new polymeric functionalized magnetic nanocatalyst containing a molybdenum Schiff base complex was prepared using a few consecutive steps. Poly (methylacrylate)-coated magnetic nanoparticles were synthesized via radical polymerization of methyl acrylate onto modified magnetic nanoparticles followed by the amidation of the methyl ester groups with hydrazine. Polymeric functionalization efficiently provides the advantage that more catalytic units can be grafted on the surface of magnetic nanoparticles. The functionalization process was continued with salicylaldehyde which introduced Schiff base groups on to the surface of the polymeric support. In the final step, the desired... 

    Synthesis, morpho-structural properties, and catalytic performances of Pt-APA@Fe3O4/GO nanocomposite based on magnetical graphene in C–C coupling reactions and photoinactivation of E. coli

    , Article Journal of Nanoparticle Research ; Volume 23, Issue 8 , 2021 ; 13880764 (ISSN) Moniriyan, F ; Sabounchei, S. J ; Yousefi, A ; Akhavan, O ; Sharif University of Technology
    Springer Science and Business Media B.V  2021
    Abstract
    Herein, a novel Pt-APA composite (APA = pyridinium bromide salt) based on magnetic graphene oxide was synthesized and used as an effective catalyst. In this way, Fe3O4 nanoparticles are grown on graphene oxide (GO) nanosheets by a simple and practical method which creates a unique nanostructure (Fe3O4/GO) through dispersing uniformly among graphene nanosheets. The resulted Pt-APA composite was obtained via adding PtCl2 to an ethanol solution of Fe3O4/GO and α-keto stabilized pyridinium ylide in related conditions. The synthesized nanocomposite structure was identified using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive... 

    Synthesis, characterization and catalytic activity of supported vanadium Schiff base complex as a magnetically recoverable nanocatalyst in epoxidation of alkenes and oxidation of sulfides

    , Article Journal of Organometallic Chemistry ; Volume 897 , 2019 , Pages 200-206 ; 0022328X (ISSN) Bagherzadeh, M ; Bahjati, M ; Mortazavi Manesh, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    A new magnetically separable nanocatalyst was successfully synthesized by immobilizing of vanadyl acetylacetonate complex, [VO(acac)2], onto silica coated magnetite nanoparticles previously functionalized with 3-aminopropyltriethoxysilane (3-APTES) and reacted by 5-bromosalicylaldehyde to form Schiff base moiety. The obtained nanocatalyst was characterized by elemental analysis (CHN), FT-IR spectroscopy, Powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma optical emission spectrometry (ICP-OES) and thermogravimetric analysis (TGA). Eventually, the resulting nanoparticles were used as catalyst for epoxidation of alkenes and... 

    Synthesis, characterisation and crystal structure of a new Cu(II)-carboxamide complex and CuO nanoparticles as new catalysts in the CuAAC reaction and investigation of their antibacterial activity

    , Article Inorganica Chimica Acta ; Volume 506 , June , 2020 Kiani, M ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Babaie, M ; Schenk Joß, K ; Sharif University of Technology
    Elsevier S. A  2020
    Abstract
    The bidentate carboxamide ligand N-(thiazole-2-yl) picolinamide (LH) was synthesized in the environmentally friendly ionic liquid TBAB, and the five-coordinated CuII-complex, [Cu(L)2(H2O)].CHCl3 (1) was synthesized from LH and copper(II)acetate. Cupric oxide [CuO] nanoparticles (2) have been prepared by the thermal decomposition of (1) as a new precursor at 600 °C for 3 h under air atmosphere. (1) was characterised using FT-IR spectroscopy, elemental analyses and its solid state structure was confirmed by single crystal X-ray diffraction. (2) were identified by FT-IR spectroscopy, X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray analysis and thermo-gravimetric...