Search for: molecular-oxygen
0.006 seconds

    Solid phase regeneration of carbonyl compounds by oxidative cleavage of carbon-nitrogen double bonds with molecular oxygen at room temperature

    , Article Letters in Organic Chemistry ; Volume 3, Issue 2 , 2006 , Pages 121-122 ; 15701786 (ISSN) Hashemi, M. M ; Akhbari, M ; Karimi Jaberi, Z ; Sharif University of Technology
    Montmorillonite K10-supported manganese(II) chloride was found to be an efficient and convenient catalyst for the oxidative cleavage of oximes, phenylhydrazones and semicarbazones to the corresponding carbonyl compounds with molecular oxygen. © 2006 Bentham Science Publishers Ltd  

    Oxidation of aromatic alcohols to carbonyl compounds with oxygen catalyzed by iron (III) chloride supported on kieselguhr

    , Article Letters in Organic Chemistry ; Volume 2, Issue 6 , 2005 , Pages 559-560 ; 15701786 (ISSN) Hashmi, M. M ; Ezabadi, A ; Karimi Jaberi, Z ; Sharif University of Technology
    Oxidation of aromatic alcohols to corresponding aldehydes and ketones have been carried out using molecular oxygen and FeCl3 supported on kieselguhr as catalyst in good yields. © 2005 Bentham Science Publishers Ltd  

    Cobalt and Manganese Salts of p-Aminobenzoic Acid Supported on Silica Gel: A Versatile Catalyst for Oxidation by Molecular Oxygen

    , Article Monatshefte fur Chemie ; Volume 134, Issue 3 , 2003 , Pages 411-418 ; 00269247 (ISSN) Hashemi, M. M ; Ahmadibeni, Y ; Sharif University of Technology
    A 1:1 molar ratio of the cobalt and manganese salts of p-amino benzoic acid supported on silica gel is an effective catalyst for the oxidation of various organic compounds in reasonable yields using molecular oxygen. The catalyst can be reused several times  

    First principles study of oxygen adsorption on nickel-doped graphite

    , Article Molecular Physics ; Volume 110, Issue 13 , Feb , 2012 , Pages 1437-1445 ; 00268976 (ISSN) Nahali, M ; Gobal, F ; Sharif University of Technology
    Density functional theory is used in a spin-polarized plane wave pseudopotential implementation to investigate molecular oxygen adsorption and dissociation on graphite and nickel-doped graphite surfaces. Molecular oxygen physisorbs on graphite surface retaining its magnetic property. The calculated adsorption energy is consistent with the experimental value of 0.1eV. It is found that substituting a carbon atom of the graphite surface by a single doping nickel atom (2.8% content) makes the surface active for oxygen chemisorption. It is found that the molecular oxygen never adsorbs on doping nickel atom while it adsorbs and dissociates spontaneously into atomic oxygens on the carbon atoms... 

    Investigation of ionic liquids based on pyridinium and imidazolium as interfacial tension reducer of crude Oil−water and their synergism with MgCl2

    , Article Journal of Petroleum Science and Engineering ; Volume 171 , 2018 , Pages 414-421 ; 09204105 (ISSN) Lashkarbolooki, M ; Ayatollahi, S ; Sharif University of Technology
    Ionic liquids (ILs) can be tailored as chemical surfactants and surface active agents to reduce the interfacial tension (IFT) of crude oil/aqueous solutions for enhanced oil recovery processes. The current investigation was aimed to explore the nature of ingenious active agents in crude oil, including asphaltene and resin, and their possible interactions with two families of ILs, namely pyridinium and imidazolium, on the IFT of crude oil/aqueous solutions, both in the presence and absence of MgCl2. To the best of our knowledge, the effect of crude oil type on the IFT of crude oil/aqueous solution containing salts and IL has not been ever investigated. Accordingly, IFTs of light, medium and... 

    Green and selective oxidation of alcohols by immobilized Pd onto triazole functionalized Fe 3O 4 magnetic nanoparticles

    , Article Journal of Chemical Sciences ; 2018 ; 09743626 (ISSN) Dadras, A ; Naimi Jamal, M. R ; Matloubi Moghaddam, F ; Ayati, S. E ; Sharif University of Technology
    Abstract: Carbonyl compounds were prepared by selective oxidation of alcohols in the presence of recoverable Fe 3O 4@ SiO 2@ Pd magnetic nanocatalyst in aqueous media as a green solvent. Molecular oxygen served as an oxidant. The catalyst was removed from the reaction media by external magnetic field, washed with methanol, and reused for six more times without any considerable reduction in its reactivity. The chemoselectivity and regioselectivity of the catalyst can serve for selective oxidation of primary alcohols in the presence of secondary ones, and for oxidation of unhindered alcohols in the presence of hindered ones. Graphical Abstract: Selective and facile oxidation of alcohols to... 

    Cyclohexene oxidation catalyzed by flower-like core-shell Fe3O4@Au/metal organic frameworks nanocomposite

    , Article Materials Chemistry and Physics ; Volume 213 , July , 2018 , Pages 472-481 ; 02540584 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Elsevier Ltd  2018
    In this study, Fe3O4@Au/metal-organic frameworks (Fe3O4@Au/MOF) nanocomposite with flower-like core-shell structure was successfully synthesized via a hydrothermal route. The as-prepared catalyst was characterized using different techniques such as FT-IR, XRD, TEM, EDX, VSM, TGA, BET, and ICP. This nanocomposite exhibited an excellent catalytic performance in selective oxidation of cyclohexene to 2-cyclohexene-1-one by using molecular oxygen as green oxidant. The influence of reaction conditions including, pressure of molecular oxygen, temperature, time, solvent, and amount of catalyst on conversion and selectivity of products were evaluated. The activation energy (Ea) of the reaction was... 

    Fabrication of novel ternary Au/CeO2@g-C3N4 nanocomposite: kinetics and mechanism investigation of 4-nitrophenol reduction, and benzyl alcohol oxidation

    , Article Applied Physics A: Materials Science and Processing ; Volume 124, Issue 6 , 2018 ; 09478396 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Springer Verlag  2018
    Abstract: Au nanoparticles supported on cerium oxide/graphitic carbon nitride (CeO2@g-C3N4) was synthesized and used as heterogeneous catalyst in redox reaction. The catalyst was characterized by different techniques such as FT-IR, XRD, FE-SEM, EDS, TEM, BET, TGA, and ICP. The as-prepared ternary nanocomposite was used as an effective catalyst for the reduction of toxic 4-nitrophenol to useful 4-aminophenol by NaBH4. The rate constant value of reduction reaction reached up to 0.106 s−1 by Au/CeO2@g-C3N4, which was 3.8, and 8.8 times higher than that of Au@CeO2 (0.028 s−1), and Au@g-C3N4 (0.012 s−1) nanocomposites, respectively. The superior catalytic performance of as-prepared catalyst in... 

    Supported PtxPd1-x bimetallic nanoparticles on ionic liquid-functionalized SiO2@graphene oxide nanocomposite and its application as an effective multiphasic catalyst

    , Article Applied Catalysis A: General ; Volume 579 , 2019 , Pages 30-43 ; 0926860X (ISSN) Kohantorabi, M ; Giannakis, S ; Gholami, M. R ; Sharif University of Technology
    Elsevier B.V  2019
    In this work, PtxPd1-x (x = 0, 0.5, and 1)nanoparticles (NPs)were synthesized on the surface of SiO2@graphene oxide which covered by 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6)ionic liquid (IL)layer. FT-IR spectroscopy, zeta potential, CHN elemental analysis, XRD, XPS, SEM, EDX, TEM, TGA, BET, and ICP-AES techniques were applied for the characterization of the multiphasic catalyst. The as-prepared nanocomposite was used as an effective heterogeneous catalyst for the oxidation of cyclohexene by molecular oxygen, as a green oxidant. Different experimental conditions such as oxygen pressure, reaction time, reaction temperature and amount of catalyst were investigated in this... 

    A systematic investigation on the bactericidal transient species generated by photo-sensitization of natural organic matter (NOM) during solar and photo-Fenton disinfection of surface waters

    , Article Applied Catalysis B: Environmental ; Volume 244 , 2019 , Pages 983-995 ; 09263373 (ISSN) Kohantorabi, M ; Giannakis, S ; Gholami, M. R ; Feng, L ; Pulgarin, C ; Sharif University of Technology
    Elsevier B.V  2019
    In this work, the role of dissolved oxygen in the solar and the photo-Fenton-mediated E. coli inactivation process was put under scrutiny. The effect of transient species that were produced in the presence of various natural organic matter isolates (NOM), namely Suwannee River (SR) NOM, Nordic Reservoir (NR) NOM, SR Humic acid (SRHA), and SR Fulvic acid (SRFA) was studied in detail. The role of 1 O2 in this reaction was systematically evaluated by modifying the O2 concentration (N2/O2 purging) and the matrix composition (10, 50, and 100% deuterium oxide (D2O) v/v). In the presence of NOM, 1 O2 was generated and the enhancement of E. coli inactivation rate due to charge transfer from triplet... 

    A comparative kinetic study on the oxidative coupling of methane over LSCF perovskite-type catalyst

    , Article Applied Catalysis A: General ; Volume 354, Issue 1-2 , 2009 , Pages 143-152 ; 0926860X (ISSN) Taheri, Z ; Seyed Matin, N ; Safekordi, A. A ; Nazari, K ; Pashne, S. Z ; Sharif University of Technology
    A gas-phase heterogeneous kinetics is described over perovskite with formula La0.6Sr0.4Co0.8Fe0.2O3-δ (LSCF) for the oxidative coupling of methane under differential conversion conditions in a microcatalytic fixed-bed reactor. The ethane (C2H6) and carbon oxides (COX) formation and methane conversion rates were obtained as a function of methane and oxygen partial pressure under experimental conditions of: 0.20 < PC H4 < 0.82 atm, 0.04 < PO2 < 0.15 atm, and 1073 < T < 1173 K. The different kinetic models were examined and two Eley-Rideal mechanisms (a and b) were successfully performed to fit the experimental data into the theoretical relations from which two mechanisms having a first step of...