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    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... 

    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.... 

    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... 

    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... 

    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... 

    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... 

    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 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... 

    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... 

    Controlled optical near-field growth of individual free-standing well-oriented carbon nanotubes, application for scattering SNOM/AFM probes

    , Article Nanophotonics ; Volume 11, Issue 21 , 2022 , Pages 4671-4686 ; 21928614 (ISSN) Yazdanfar, P ; Heydarian, H ; Rashidian, B ; Sharif University of Technology
    De Gruyter Open Ltd  2022
    Abstract
    Exploiting localized heat-generation density and the resulting enhanced temperature-rise for controlled growth of carbon nanotubes (CNTs) is reported, and its potentials for batch-production of high-quality CNT probes are demonstrated. Optical near field chemical vapor deposition (ONF-CVD) benchtop fabrication schemes are developed for the localized integration of individual well-aligned carbon nanotubes without bending/buckling exactly at desired nanoscale sites. It is demonstrated that generating self-aligned catalyst nanoparticles superimposed on top of silicon nanotips, along with near-field induced absorption confinement, provide the ability to localize the generated heat at the... 

    NiSe2Nanoparticles supported on halloysite sheets as an efficient electrocatalyst toward alkaline oxygen evolution reaction

    , Article Energy and Fuels ; Volume 36, Issue 23 , 2022 , Pages 14331-14340 ; 08870624 (ISSN) Taherinia, D ; Hatami, H ; Mirzaee Valadi, F ; Akbarzadeh, E ; Sharif University of Technology
    American Chemical Society  2022
    Abstract
    The oxygen evolution reaction (OER) with its sluggish kinetics has imposed a significant barrier to the sustainable and green generation of hydrogen fuel (via electrolysis of water) and the development of metal-air batteries. In this study, we report an efficient and novel OER electrocatalyst based on NiSe2nanoparticles (NPs) and the naturally abundant halloysite clay mineral. The NiSe2/halloysite nanocomposite (NiSe2/H) was prepared by a simple one-step hydrothermal route. The electrocatalytic performance of the as-synthesized nanocomposite and its components (pristine NiSe2and halloysite) toward OER in 1.0 KOH solution was examined. The NiSe2/H nanocomposite exhibited a significantly... 

    Facile synthesis of N-doped hollow carbon nanospheres wrapped with transition metal oxides nanostructures as non-precious catalysts for the electro-oxidation of hydrazine

    , Article Journal of Electroanalytical Chemistry ; Volume 873 , 2020 Taghaddosi, S ; Rezaee, S ; Shahrokhian, S ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In the present work, N-doped hollow carbon nanospheres (N-HCNSs) is prepared by direct carbonization of polyaniline-co-polypyrrole (PACP) hollow spheres without template needing. Two different NiO nanostructures (nanosheets and nanowires) are prepared by forming a shell around the N-HCNSs via simple hydrothermal/calcination processes (NiO-NSs@N-HCNSs and NiO-NWs@N-HCNSs). The morphology and structure of the nanostructures are characterized using field emission scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The prepared nanocomposites are used as catalysts for the electrocatalytic... 

    Stereoselective synthesis ofβ-Amino ketones via direct mannich-type reaction catalyzed with SO 2- 4/TiO 2 and SO 2- 4/nano TiO 2

    , Article Synthetic Communications ; Volume 39, Issue 24 , 2009 , Pages 4441-4453 ; 00397911 (ISSN) Samet, M ; Eftekhari Sis, B ; Mahmodi Hashemi, M ; Farmad, F ; Sharif University of Technology
    2009
    Abstract
    At room temperature, SO 2- 4/nano-TiO 2 efficiently catalyze the direct Mannich-type reaction of varieties of in situ-generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the correspondingβ-amino ketones in good to high yields with good to excellent stereoselectivity. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency  

    Deep oxidative desulfurization via rGO-immobilized tin oxide nanocatalyst: Experimental and theoretical perspectives

    , Article Advanced Powder Technology ; Volume 33, Issue 3 , 2022 ; 09218831 (ISSN) Salmanzadeh Otaghsaraei, S ; Kazemeini, M ; Hasannia, S ; Ekramipooya, A ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    In this contribution, reduced grapheme oxides (rGO) with immobilized tin oxide (SnO2) nanocatalysts were synthesized via the Incipient Wetness Impregnation (IWI) method. To characterize the SnO2/rGO composites, several analyses including the; XRD, Raman, FTIR, ICP-OES, BET-BJH, XPS, TEM, and TPD were utilized. Then the effects of parameters including reaction time, total metal loading, and the initial sulfur concentration of model fuel in the dibenzothiophene (DBT) oxidation desulfurization process were evaluated. After determining the optimal conditions for the aforementioned parameters, the influences of 3 effective factors of the molar ratio of oxidant/substrate (O/S), the molar ratio of... 

    Electrochemical properties of Ni3S2@MoS2-rGO ternary nanocomposite as a promising cathode for Ni–Zn batteries and catalyst towards hydrogen evolution reaction

    , Article Renewable Energy ; Volume 194 , 2022 , Pages 152-162 ; 09601481 (ISSN) Salarizadeh, P ; Rastgoo Deylami, M ; Askari, M. B ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The development of active and stable materials has great importance for the commercialization of nickel-zinc (Ni–Zn) batteries and hydrogen production. Transition metal sulfides have good theoretical properties for these applications. In this research, we present the synthesis and characterization of Ni3S2@MoS2 nanocatalyst and its hybrid with reduced graphene oxide (Ni3S2@MoS2-rGO). The capability of these materials is investigated as cathode material for Ni–Zn batteries and hydrogen evolution in alkaline media. In the case of Ni–Zn batteries, the assembled Ni3S2@MoS2-rGO//Zn battery shows a discharge capacity of 249.3 mAh g−1 with coulombic efficiency of 97.2%, showing a higher... 

    Organocopper-based magnetically recoverable and reusable nanocatalyst for efficient synthesis of novel 1,2,3-triazole-based sulfonamides in green medium

    , Article Research on Chemical Intermediates ; Volume 44, Issue 1 , 2018 , Pages 601-612 ; 09226168 (ISSN) Saeidian, H ; Sadighian, H ; Arabgari, M ; Mirjafary, Z ; Ayati, S. E ; Najafi, E ; Matloubi Moghaddam, F ; Sharif University of Technology
    Springer Netherlands  2018
    Abstract
    Abstract: We report robust green synthesis of novel 1,2,3-triazole-based sulfonamides bearing different motifs such as fluorine under click conditions in presence of a copper-based magnetically recoverable and reusable heterogeneous nanocatalyst. The organocopper catalyst at 0.5 mol.% was highly recyclable (up to five times) when recovered using an external magnet without significant loss in catalytic activity. The mild reaction conditions and excellent yields (69–95 %) make this protocol an attractive method for efficient synthesis of the title compounds. The structure of product 3a was determined by Röntgen crystal structure analysis. Graphical Abstract: [Figure not available: see... 

    Monodentate palladium(0)-[60]fullerene complexes of diphosphine ligands as efficient and sustainable nanocatalysts for the Mizoroki-Heck coupling reaction of aryl chlorides

    , Article New Journal of Chemistry ; Volume 41, Issue 18 , 2017 , Pages 9701-9709 ; 11440546 (ISSN) Sabounchei, S. J ; Hosseinzadeh, M ; Zarepour Jevinani, M ; Ghanbari, B ; Sharif University of Technology
    Royal Society of Chemistry  2017
    Abstract
    Two mononuclear coordination complexes of fullerene[60] with Pd(dba)2 (dba = dibenzylideneacetone), [(η2-C60)Pd(Ph2P(CH2)2PPh2C(H)C(O)R)2] (R = C10H7 (1), C6H4Cl (2)), have been prepared using a simple procedure to explore new directions in palladium catalysis and nanocarbon chemistry. The palladium(0)-[60]fullerene complexes incorporating unsymmetrical phosphorus ylides have been characterized by 1H, 13C and 31P NMR spectroscopic methods and other conventional techniques such as IR, TGA, SEM, ICP-OES, EDX and TEM analysis. Attributed to the enhanced dispersity and uniform size of the Pd nanoparticles with phosphine-functionalized fullerenes, the prepared catalysts exhibited comparable... 

    Ruthenium/Ruthenium oxide hybrid nanoparticles anchored on hollow spherical Copper-Cobalt Nitride/Nitrogen doped carbon nanostructures to promote alkaline water splitting: Boosting catalytic performance via synergy between morphology engineering, electron transfer tuning and electronic behavior modulation

    , Article Journal of Colloid and Interface Science ; Volume 626 , 2022 , Pages 1070-1084 ; 00219797 (ISSN) Rezaee, S ; Shahrokhian, S ; Sharif University of Technology
    Academic Press Inc  2022
    Abstract
    Exploring bi-functional electrocatalysts with excellent activity, good durability, and cost-effectiveness for electrochemical hydrogen and oxygen evolution reactions (HER and OER) in the same electrolyte is a critical step towards a sustainable hydrogen economy. Three main features such as high density of active sites, improved charge transfer, and optimized electronic configuration have positive effects on the electrocatalyst activity. In this context, understanding structure–composition–property relationships and catalyst activity is very important and highly desirable. Herein, for the first time, we present the design and fabrication of novel MOF-derived ultra-small Ru/RuO2 nanoparticles... 

    Engineered FeVO4/CeO2 nanocomposite as a two-way superior electro-Fenton catalyst for model and real wastewater treatment

    , Article Journal of Environmental Sciences (China) ; Volume 97 , 2020 , Pages 110-119 Rahman Setayesh, S ; Nazari, P ; Maghbool, R ; Sharif University of Technology
    Chinese Academy of Sciences  2020
    Abstract
    FeVO4/CeO2 was applied in the electro-Fenton (EF) degradation of Methyl Orange (MO) as a model of wastewater pollution. The results of the characterization techniques indicate that FeVO4 with triclinic structure and face-centered cubic fluorite CeO2 maintained their structures during the nanocomposite synthesis. The effect of applied current intensity, initial pollutant concentration, initial pH, and catalyst weight was investigated. The MO removal reached 96.31% and chemical oxygen demand (COD) removal 70% for 60 min of the reaction. The presence of CeO2 in the nanocomposite plays a key role in H2O2 electro-generation as a significant factor in the electro-Fenton (EF) system. The metal...