Search for: heterogeneous-catalyst
Total 54 records
Copper immobilized onto polymer-coated magnetic nanoparticles as recoverable catalyst for ‘click’ reaction, Article Applied Organometallic Chemistry ; Volume 31, Issue 5 , 2017 ; 02682605 (ISSN) ; Bayat, A ; Valizadeh, H ; Sharif University of Technology
Copper supported on polymer-coated magnetic nanoparticles was designed and synthesized as a separable heterogeneous catalyst. The catalyst was fully characterized using several techniques such as Fourier transform infrared and energy-dispersive X-ray spectroscopies, scanning and transmission electron microscopies, X-ray diffraction, vibrating sample magnetometry, thermogravimetric analysis and inductively coupled plasma atomic emission spectrometry. All results showed that copper was successfully supported on the polymer-coated magnetic nanoparticles. Also, results showed that the synthesized material can be used as an efficient catalyst for the preparation of a series of 1,4-disubstituted...
Palladium nanoparticle-decorated magnetic pomegranate peel-derived porous carbon nanocomposite as an excellent catalyst for suzuki–miyaura and sonogashira cross-coupling reactions, Article Applied Organometallic Chemistry ; Volume 32, Issue 10 , 2018 ; 02682605 (ISSN) ; Habibi, Z ; Sharif University of Technology
Porous carbon (PC) material was prepared from the carbonization of pomegranate peel waste. Subsequently, magnetically separable Fe3O4@PC was synthesized from Fe3O4 nanoparticles decorated on PC by the co-precipitation method of iron ions. Finally, Fe3O4@PC was successfully decorated with palladium nanoparticles in a simple route by reducing H2PdCl4 in the presence of sodium dodecylsulfate, which was used as both surfactant and reducing agent. Additionally, the effect of temperature on the carbonization process was studied. The Pd/Fe3O4@PC nanocomposite was used as an efficient and heterogeneous catalyst for Suzuki–Miyaura and Sonogashira cross-coupling reactions in an environmentally...
Gold-Decorated 3D 2,6-diaminopyridine network: a robust catalyst for the bromination of aromatic compounds, Article Industrial and Engineering Chemistry Research ; Volume 57, Issue 37 , 2018 , Pages 12314-12322 ; 08885885 (ISSN) ; Keshavarzi, N ; Hosseini, S. H ; Matloubi Moghaddam, F ; Sharif University of Technology
American Chemical Society 2018
This article reports the synthesis of a magnetic heterogeneous catalyst through the decoration of gold ions onto the cross-linked polymeric nanocomposite from 2,6-diaminopyridine. The activity of the resulting catalyst was then evaluated in the bromination of aromatic compounds. The nitrogen rich support showed a high affinity to gold ions, and the measured content of Au was 0.76 mmol g-1. The structure of the catalyst was fully characterized by using Fourier-transform infrared spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, transmission electron microscopy, scanning electron microscope, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller surface area...
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) ; 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...
SBA-15-supported copper (II) complex: an efficient heterogeneous catalyst for azide-alkyne cycloaddition in water, Article Scientia Iranica ; Volume 25, Issue 3C , 2018 , Pages 1335-1343 ; 10263098 (ISSN) ; Mahmoudi, H ; Amini, M ; Gautam, S ; Chae, K. H ; Sharif University of Technology
Sharif University of Technology 2018
The reaction of the functionalized mesoporous SBA-15 in absolute ethanol with copper (II) acetate afforded a novel CuII-Schiff base/SBA-15 catalyst. The compound CuII-Schiff base/SBA-15 was characterized by IR spectroscopy, small-angle X-ray diffraction (SAX), Energy Dispersive X-ray Spectroscopy (EDXS), X-ray Absorption Near Edge Structure (XANES), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), and N2 adsorption/desorption studies. Further, the catalytic activity of this well-defined material was tested in three-component Copper-catalyzed Azide-Alkyne Cycloaddition (CuAAC) reactions to obtain 1,4-disubstituted-1,2,3-triazoles in good to excellent yields from an...
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) ; 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...
Phosphomolybdic acid/graphene oxide as novel green catalyst using for biodiesel production from waste cooking oil via electrolysis method: optimization using with response surface methodology (RSM), Article Fuel ; Volume 287 , March , 2021 ; Tahvildari, K ; Hemmati, A ; Aberoomand azar, P ; Safekordi, A ; Sharif University of Technology
Elsevier Ltd 2020
In this study, biodiesel (FAME) was prepared using a novel heterogeneous catalyst of phosphomolybdic acid (H3PMo12O40, HPMo)/support graphene oxide (GO). The characterization of the catalyst was evaluated by SEM, EDX, Map analysis, TEM, FT-IR, and Raman analyses. The production of biodiesel from waste cooking oil (WCO) was carried out by the electrolysis method. The process of the trans-esterification reaction was optimized by applying the response surface methodology (RSM) based on the central composite design (CCD) approach. The effects of four independent variables of methanol to oil molar ratio (6–12 mol:mol), catalyst weight (0.5–1.5 wt%), time (8–24 h), and voltage (30–70 V) were...
Copper ferrite nanoparticles catalyzed formation of β-ketophosphonates via oxyphosphorylation of styrenes with H-phosphonates: a DFT study on UV–vis absorption spectra, Article Catalysis Communications ; Volume 141 , 15 June , 2020 ; Daneshfar, M ; Azaryan, R ; Pirat, J. L ; Sharif University of Technology
Elsevier B.V 2020
Typical copper ferrite nanoparticles (CuFe2O4) were used as a catalyst for one-pot synthesis of β-ketophosphonates via the reaction of alkenes with H-phosphonates under conventional heating conditions. The catalyst was prepared by using the coprecipitation method and was analyzed by physiochemical techniques. By using this catalyst system, several types of useful and new β-ketophosphonate products were obtained in very good to excellent yields under optimized reaction conditions in a novel way. Furthermore, the catalyst is recyclable and reusable from the reaction. © 2020 Elsevier B.V
A novel magnetic polyacrylonotrile-based palladium core−shell complex: a highly efficient catalyst for synthesis of Diaryl ethers, Article Journal of Organometallic Chemistry ; Volume 916 , 14 June , 2020 ; Jarahiyan, A ; Eslami, M ; Pourjavadi, A ; Sharif University of Technology
Elsevier B.V 2020
The present article describes the synthesis of a new magnetic polyacrylonitrile-based Pd catalyst involving polyacrylonitrile modified via 2-aminopyridine as an efficient support to immobilize Pd nanoparticles. The simple reusability, easy separation and high stability of this Pd complex make it an excellent candidate to generate a C–O bond via Ph-X activation which is a really important subject in achieving biologically active compounds. It is worth to note access to good and high yields as well as broad substrate scope have resulted from superior reactivity of this catalyst complex. Furthermore, the structure of the magnetic polyacrylonitrile-based heterogeneous catalyst was characterized...
Transesterification of sunflower oil to biodiesel fuel utilizing a novel K2CO3/Talc catalyst: Process optimizations and kinetics investigations, Article Industrial Crops and Products ; Volume 156 , 2020 ; Kazemeini, M ; Sadjadi, S ; Sharif University of Technology
Elsevier B.V 2020
A novel efficient and cost-effective heterogeneous catalyst for the production of biodiesel from transesterification of sunflower oil was prepared through the impregnation of K2CO3 upon the Talc material. The physicochemical features of the catalyst were studied through several characterization analyses. The effect of the K2CO3 loading was investigated by comparing the catalytic activity of various prepared catalysts. Moreover, the effect of the calcination temperature upon the catalytic activity was examined. To maximize the yield of the produced biodiesel fuel, reaction variables such as the reaction time and temperature, catalyst concentration, and methanol: oil molar ratio were...
Article JAOCS, Journal of the American Oil Chemists' Society ; Volume 98, Issue 6 , 2021 , Pages 633-642 ; 0003021X (ISSN) ; Kazemeini, M ; Rahmani, M. H ; Zehtab Salmasi, M ; Sharif University of Technology
John Wiley and Sons Inc 2021
Kaolin clay material was loaded with potassium carbonate by impregnation method as a novel, effective, and economically heterogeneous catalyst for biodiesel production of sunflower oil via the transesterification reaction. The structural and chemical properties of the produced catalysts were characterized through several analyses including the X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer–Emmett–Teller specific surface area. These revealed the best catalyst for the investigated reaction among different ones prepared based upon various impregnation extent of the potassium carbonate. The influence of this parameter was examined through a...
A regioselective approach to synthesize indolyl diketone derivatives via magnetic polymeric copper-catalyst, Article Catalysis Letters ; 2021 ; 1011372X (ISSN) ; Jarahiyan, A ; Pourjavadi, A ; Sharif University of Technology
Abstract: In the present paper, an efficient Cu-catalyzed regioselective acylation of indoles with phenylglyoxals was developed which is the first example of indolyl diketones synthesis by a heterogeneous catalyst. The magnetic polyacrylonitrile was synthesized through anchoring acrylonitrile monomers on Fe3O4 nanoparticles surface and then modified with 2-aminopyridine. At the final step, copper nanoparticles were immobilized onto the polymeric support containing stable ligands from functionalized nitrile groups of polyacrylonitrile. The different techniques such as Fourier transmission infrared spectroscopy, X-ray diffraction, Field emission scanning electron microscopy, Transmission...
Immobilization of Au nanoparticles on poly(glycidyl methacrylate)-functionalized magnetic nanoparticles for enhanced catalytic application in the reduction of nitroarenes and Suzuki reaction, Article Applied Organometallic Chemistry ; Volume 34, Issue 10 , 2020 ; Kohestanian, M ; Keshavarzi, N ; Sharif University of Technology
John Wiley and Sons Ltd 2020
We report a novel strategy for the synthesis of magnetic nanocomposite for highly efficient catalysis. Poly(glycidyl methacrylate) (PGMA) chains were grafted to the surface of magnetic nanoparticles (MNPs) through surface-initiated reversible addition-fragmentation chain transfer polymerization. Then, the oxirane rings in the PGMA chains were opened with 2,6-diamino pyridine (DAP) molecules as ligands to prepare the solid support. Finally, this magnetic nanocomposite was used for the immobilization of gold nanoparticles. Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, gel permeation...
Synthesis of some new 1,4-distyrylbenzenes using immobilized palladium nanoparticles on silica functionalized morpholine as a recyclable catalyst, Article Synthesis ; Issue 10 , 2011 , Pages 1609-1615 ; 00397881 (ISSN) ; Gharavi, A ; Nezhad, M. R. H ; Panahi, F ; Sharbati, M. T ; Sharif University of Technology
Some new 1,4-distyrylbenzene derivatives were synthesized by using immobilized palladium nanoparticles on silica-bonded N-propyl morpholine (PNP-SBNPM) as a heterogeneous catalyst. These one-pot reactions afforded a range of stereoselective, symmetrical (E)-1,4-distyrylbenzene derivatives with high yields (78-90%). The green catalyst system is recyclable and allows facile product isolation. The recycled catalyst could be reused six times without appreciable loss of catalytic activity