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    Synthesis of α-aminophosphonates in the presence of a magnetic recyclable Fe3O4@SiO2-2mimSO3H nanocatalyst

    , Article Bulletin of the Chemical Society of Japan ; Vol. 87, issue. 9 , 2014 , pp. 982-987 ; ISSN: 00092673 Shakourian-Fard, M ; Rezayan, A. H ; Kheirjou, S ; Bayat, A ; Hashemi, M. M ; Sharif University of Technology
    A highly efficient magnetic Brønsted acid catalyst was synthesized based on immobilization of 2-methylimidazole functionalized by chlorosulfonic acid on the surface of silica-coated magnetic nanoparticles (Fe3O4@SiO2-2mimSO3H). The catalyst has an excellent activity and recyclable for at least 6 reaction runs and is proven to be highly effective in the synthes is of α-aminophosphonate compounds in a green way. The facile recovery of the catalyst is carried out by applying an external magnet device. It is both "green" and efficient. The catalyst was fully characterized by techniques of TEM, SEM, FT-IR, TGA, and elemental analysis (CHNS)  

    Renewable hydrogen production by ethylene glycol steam reforming over Al2O3 supported Ni-Pt bimetallic nano-catalysts

    , Article Renewable Energy ; Volume 128 , 2018 , Pages 188-199 ; 09601481 (ISSN) Larimi, A ; Khorasheh, F ; Sharif University of Technology
    The steam reforming of ethylene glycol, a simple model compound for biomass-derived liquids, is considered to be an environmentally green process for producing renewable hydrogen. Both Pt and Ni species are known for their catalytic activity under steam reforming reaction conditions. In this investigation, alumina supported Ni-Pt bimetallic catalysts (X wt% Ni-Y wt% Pt/Al2O3 named XNi-YPt) were employed for steam reforming of ethylene glycol. The prepared catalysts were characterized by XRD, BET, H2-TPR, H₂-Chemisorption, and TEM. It was observed that Ni/Pt ratio strongly affected the redox behavior, BET surface area, and particle size of the samples that in turn affected their catalytic... 

    Synthesis of MoS2 Nanoparticles and Their Application as Nanocatalyst for Hydrodesulfurization Process

    , M.Sc. Thesis Sharif University of Technology Parviz, Dorsa (Author) ; Kazemeini, Mohammad (Supervisor) ; Rashidi, Alimorad (Supervisor)
    Highly active unsupported MoO3 and (Co) MoO3 catalysts were synthesized utilizing the solution combustion method where the Ammonium molybdate powder and an organic additive were used as precursors. Different organic materials including Ethylene Diamin Tetra-acetic acid (EDTA), Polyethylene Glycol 200 (PEG 200), Sorbitol and Urea were used as additive in order to investigate the effect of additive structure on morphology and particle size of products. Also various reaction parameters such as the additive/Mo molar ratio, concentration of metal ion in solution, pH of the reaction and temperature of the synthesis media were changed to study effects on product morphology and size. Outcomes were... 

    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)
    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... 

    Alkane Production from Biomass,Using Nano-Heterogeneous Catalysts

    , M.Sc. Thesis Sharif University of Technology Bastan, Farzad (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor)
    Reduced supplies of fossil fuels worldwide attention to the economic and energy-efficient processes for the production of fuel from renewable sources is diverted.Biomass has the potential shown because it has features such as frequency and is renewable. Because of the high solubility of hydrocarbons derived from biomass in large amounts of water and oxygen, the process is then performed on the aqueous phase is considered. Recent research for the production of alkanes by the deformation of the aqueous phase (Aqueous Phase Reforming) by Catalyst on hydrocarbons derived from biomass, such as glycerol, ethylene glycol, sorbitol, glucose, and etc. has been done. Here is our attempt to use the APR... 

    Synthesis of Graphene-Based Magnetic Nanocatalyst Supported Ag Nanoparticles for Alcohols Oxidation

    , M.Sc. Thesis Sharif University of Technology Ataei Kachouei, Shiva (Author) ; Mahmoodi Hashemi, Mohammad (Supervisor)
    In this thesis the graphene-based magnetic nanocatalyst was synthesized. The surface of this catalyst was cavered by silica and AgNPs. In addithion of simple sepration by magnetbar, yeild of reaction was promoted by surface modification. Catalyst structure was verified by transmission electron microscopy , scanning electron microscope, fourier transform infrared spectroscopy, X-ray diffraction and Energy dispersive spectroscopy.At the end catalytic activity was examined by oxidation reaction in persense of different alcohols. The oxidation of benzylic alcohol with electron withdrawing substituents was more difficult and the yield was lower, but electron donor substituents effect positively... 

    Synthesis of Nano H-ZSM-5 for Methanol Conversion to Propylene

    , M.Sc. Thesis Sharif University of Technology Firoozi, Mohammad (Author) ; Baghghalha, Morteza (Supervisor) ; Asadi, Mousa (Co-Advisor)
    Nano and microsize H-ZSM-5 were synthesized by hydrothermal crystallization method with same batch composition to investigate the effect of crystallite size of H-ZSM-5 in the methanol conversion to propylene (MTP) process. The average particle size of nano and microsize H-ZSM-5 were obtained in the range of 0.15- 0.2 and 1- 2 µm, respectively. Also, optimized catalyst of Petrochemical Research and Technology Company was synthesized using terapropylammonium bromide as template. Nowadays, terapropylammonium bromide (TPABr) is cheeper than terapropylammonium hydroxide (TPAOH); therefore we used it as tamplate. Activity tests were conducted at operating conditions of T= 460˚C, P=1 atm and WHSV... 

    Synthesis of a Nanocatalyst for Selective Hydrogenation of Acetylene in Presence of Ethylene

    , M.Sc. Thesis Sharif University of Technology Bazzazzadegan, Hadi (Author) ; Kazemeini, Mohammad (Supervisor) ; Rashidi, Ali Morad (Supervisor)
    In this research a novel palladium nanocatalyst was synthesized over single-wall carbon nanotube (SWNT) support and then applied in the selective hydrogenation of acetylene in an ethylene rich-flow stream. This nanocatalyst displayed a very promising selectivity toward ethylene production upon rising of the temperature, as well as suppressing oligomer formation during acetylene hydrogenation. It was rationalized that the overwhelming governing mechanism for the acetylene hydrogenation over the 0.48 wt% Pd/SWNT was the hydrogen transfer. Furthermore, new operating conditions for selective hydrogenation of acetylene in ethylene rich-flow were introduced through which the selective... 

    , M.Sc. Thesis Sharif University of Technology Hatami, Mojgan (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Inert gold become catalytically active when dispersed in the form of nanoparticles. Isolated gold nanoparticles have demonstrated high catalytic activity for both oxidation and reduction reactions. In order to obtain high catalytic activity, gold nanoparticles are generally dispersed on support materials, among which oxides are commonly used. However, a substantial decrease in activity and selectivity of the immobilized catalysts is frequently observed due to the heterogeneous nature of these support materials in reaction media. In the course of our study on the metal-based catalysis for synthesis of organic compounds, we herein report that rod-shaped Au nanoparticles in aqua solution... 

    Design a New Magnetic Nanocatalyst Based on Palladium (II) and Its Application for the Selective Oxidation Reaction of Alcohol to Aldehyde

    , M.Sc. Thesis Sharif University of Technology Sadeghi Erami, Mehran (Author) ; Matloubi Moghaddam, Firouz (Supervisor) ; Sajadi, Ali Akbar (Supervisor)
    In the first chapter of the thesis the synthesis of indolylsulfanyl acetamide derivatives using thio-oxindoles has been reported. The properties of this reaction are, one-pot, without using catalysts, acetonitrile solvent and the raw material is available. This reaction has high yield and seperation products is done using column chromatography. Indole derivatives has various medicinal and biological properties and synthetic products in this project has indole ring, aldehyde and amide functional groups. In the second chapter of the thesis, a new magnetic nanocatalyst has been designed. The magnetic nanoparticles were coated with triazole ligand and then palladium (II) ion was loaded onto the... 

    Oxidation of Sulfides and Olefins in the Presence of Nanocluster Polyoxotungstate–intercalated Layered Double Hydroxide Nanoparticles as a Catalyst

    , M.Sc. Thesis Sharif University of Technology Qoreishi Kavardi, Atefeh Sadat (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    In this study, polyoxometalate (POM) intercalated in the layered double hydroxide (LDH) was synthesized by a selective ion-exchange method. For this purpose, the nanocluster [VW12O40]3- was immobilized on the Mg2+/A13+/Cl–LDH support. The heterogeneous catalyst was characterized by FT-IR, XRD, SEM and analysis of ICP. The LDH-POM was applied as a catalyst in efficient oxidation of sulfides to sulfoxides using UHP as oxidant and CH3OH/ CH¬2¬Cl¬2 ¬as a solvent at room temperature, as well as epoxidation of olefins using TBHP as an oxidants and C¬2H4Cl2 as a solvent in 84°C. This catalyst showed excellent catalytic activities for a substrate/catalyst ratio (200:1). For example, this catalytic... 

    Synthesis and Characterization of Cobalte Ferrite and Nickel Ferrite Nanocatalysts and Their Application in the C-X Bond Activation Reaction

    , M.Sc. Thesis Sharif University of Technology Aliabadi, Ali (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Nowadays application of metallic catalysts in many of the organic reactions has been developed; therefore, different types of catalysts have been produced and used. In this way, in the first part of this thesis magnetic cobalt ferrite and nickel ferrite nanocatalysts were synthesized using co-precipitation method and their activity as catalyst was investigated in C-O bond formation reaction. This reaction was carried out between different types of aryl alcohols and aryl halides with good to excellent yields. The results showed that using N,N-dimethyl formamide as solvent, potassium carbonate as base and 5mol% of nanocatalysts at 80°C are the optimized condition for this reaction. In the... 

    Application of Spinel Ferrite and Samarium Catalysts in the Amination, Cyanation and other Organic Transformations

    , M.Sc. Thesis Sharif University of Technology Gholamtajari, Milad (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    In the first section, due to the important role of nanocatalysts in different fields of chemistry, magnetic metal ferrite nanoparticles were synthesized. Cobalt Cupper ferrite magnetic nanoparticles were synthesized using co-precipitation method and were characterized. The carbon−heteroatom bond forming reaction is one of the most important reactions in organic synthesis, pharmaceutical, dye, agrochemical, and biomolecules.1 Therefore, improvement of efficient methodologies for generating carbon−heteroatom bonds received considerable attention. An efficient protocol was developed for the nano CoCuFe2O4 catalyzed C-N and C-S bond formation. By this catalytic system, both amine and... 

    Synthesis of Magnetically Recyclable Core-shell Nanocatalysts for Epoxidation of Alkenes and Reduction of Sulfoxide to Sulfides and Oxygen Atom transfer by Mo(VI) Complexes

    , Ph.D. Dissertation Sharif University of Technology Haghdoost Manjili, Mohammad Mehdi (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    In the first part of this thesis, the application of core-shell magnetic nanoparticles supported V(V), Mo(VI) and Mn(III) complexes in the catalytic oxidation and reduction reactions was discussed. A magnetically recyclable vanadium(V) catalyst was synthesized by covalent anchoring of VO(salen)Cl on silica coated Fe3O4 nanoparticles. These nanoparticles were efficient catalysts for selective oxidation of sulfides to corresponding sulfoxides with urea hydrogen peroxide in excellent yields. Leaching and recycling experiments revealed that the nanocatalyst can be applied for nearly complete oxidation of sulfides for at least five successive cycles. A manganese(III) complex was immobilized on... 

    Synthesis, Characterization and Catalytic Activity of Supported Vanadium Schiff Base Complex as a Magnetically Recoverable Nanocatalyst in Epoxidation of Alkenes and Oxidation Of Sulfides

    , M.Sc. Thesis Sharif University of Technology Bahjati, Mohammad (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    In this project, a new magnetically recoverable nanocatalyst was developed by immobilizing of vanadyl acetylacetonate, [VO(acac)2], onto surface of silica coated magnetite nanoparticlest that modified by reaction between 3-aminopropylthriethoxy silane and 5-bromosalicylaldehyde. In the first step, magnetite cores were synthesized by co-precipitation method and coated by tetraethyl orthosilicate (TEOS) and modified by 3-aminopropyltriethoxy silane to provide a precursor for Schiff base condensation reaction. In the next step, amino-functionalized silica coated magnetite nanoparticles were reacted by 5-bromosalicylaldehyde to formation a Schiff base moiety onto surface of magnetite coated... 

    Immobilazation of Manganese-Porphyrin Complex on Magnetic Nanoparticles and its Application as a Catalyst for the Epoxidation of Olefins and Oxidation of Sulfides

    , M.Sc. Thesis Sharif University of Technology Hosseini, Morteza (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    The goal of this study is to synthesise and study the catalytic properties of a Mn-Porphyrin complex fixed on a magnetic nanoparticle bed. This nanocatalyst was used in oxidation of sulfides and epoxylation of olefin. In the multistage synthesis of this catalyst, iron oxide magnetic nanoparticles were first prepared, then, by silanizing these nanoparticles, and then using the 3-chloropropyltrimethoxy methanol reactor, Immobilzation the material on the substrate and immediately react in reaction Substitution of the nucleus of friendship and using a sodium azide reaction, bromide is replaced by azide. Subsequently, by synthesising 4-hydroxy porphyrin and replacing one of its positions with... 

    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)
    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... 

    Synthesis, Characterization and Catalytic Application of rGO based Tin Oxide Nanocatalyst in Oxidative Desulfurization Process

    , M.Sc. Thesis Sharif University of Technology Salmanzadeh Otaghsaraei, Sahar (Author) ; Kazemeini, Mohammad (Supervisor) ; Hasannia, Saeed (Supervisor)
    In recent years, graphene-based materials have received much attention due to their prominent physicochemical properties such as high specific surface area, high mechanical strength and rich surface functional groups. In addition to these properties, low cost and environmental safety make graphene-based materials a green catalyst for many catalytic processes, including oxidative desulfurization. Tin oxide is a substance with strong acidic sites. Recent studies have shown that the oxidative desulfurization process using tin oxide nanoparticles is a new method for producing cleaner diesel fuels. In this study, rGO based tin oxide nanocatalyst was synthesized. To synthesize this catalyst,... 

    Kinetics Investigation of Oxygen Evolution from Water Oxidation in the Presence of Bismuth Vanadate Nanocatalysts

    , M.Sc. Thesis Sharif University of Technology Moradpour, Amin (Author) ; Rahman Setayesh, Shahrbanoo (Supervisor)
    In this project, BiVO4 , Mn3O4 and BiVO4- Mn3O4 nanocatalysts were synthesized using the hydrothermal method. The properties of these nanocatalysts were determined by XRD, SEM, FT-IR, DRS, PL, ICP, EDX, BET and AA techniques. Analysys XRD patterns and SEM images of samples confirmed monoclinic structure for BiVO4 and tetragonal structure for Mn3O4. The DRS and PL spectra showed adctrease in the band gap and electron – hole pair recombination for BM 60:40 relative to BiVO4. Oxygen production was studied in the presence of different percentages of BiVO4 and Mn3O4 in BiVO4 - Mn3O4 nanocomposite and was observed that the 60:40 wt.% (Bismuth vanadate 60% and manganese oxide 40%) produced more... 

    Optimization and Continuous Synthesis of Artemisinin Using Core-Shell Nano-Catalysts by Means of Micro-Rector

    , Ph.D. Dissertation Sharif University of Technology Tamtaji, Mohsen (Author) ; Kazemeini, Mohammad (Supervisor)
    Artemisinin as a natural peroxide possess a high anti parasite, and antivirus (Covid-19) properties which could be synthesized through the photooxygenation of dihydroartemisinic acid. This production possesses a lot of difficulties, for example, homogeneous catalyst is used for the photooxygenation reaction which makes photocatalyst and solvent non-reusable. In addition, separation of products from solvent and photocatalysts is difficult. Photooxygenation needs high pressure and low temperature which is very costly. Besides, because of several by-products which are producing during photooxygenation and protonation reactions, Artemisinin yield decreases. The aim of this study is to optimize...