Relevant bibliographies by topics / Copper catalysi

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Academic literature on the topic 'Copper catalysi'

Author: Grafiati
Published: 9 March 2023

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Journal articles on the topic "Copper catalysi"

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Dadashi-Silab, Sajjad, and Krzysztof Matyjaszewski. "Iron Catalysts in Atom Transfer Radical Polymerization." Molecules 25, no. 7 (April 3, 2020): 1648. http://dx.doi.org/10.3390/molecules25071648.

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Catalysts are essential for mediating a controlled polymerization in atom transfer radical polymerization (ATRP). Copper-based catalysts are widely explored in ATRP and are highly efficient, leading to well-controlled polymerization of a variety of functional monomers. In addition to copper, iron-based complexes offer new opportunities in ATRP catalysis to develop environmentally friendly, less toxic, inexpensive, and abundant catalytic systems. Despite the high efficiency of iron catalysts in controlling polymerization of various monomers including methacrylates and styrene, ATRP of acrylate-based monomers by iron catalysts still remains a challenge. In this paper, we review the fundamentals and recent advances of iron-catalyzed ATRP focusing on development of ligands, catalyst design, and techniques used for iron catalysis in ATRP.
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Trigoura, Leslie, Yalan Xing, and Bhanu P. S. Chauhan. "Recyclable Catalysts for Alkyne Functionalization." Molecules 26, no. 12 (June 9, 2021): 3525. http://dx.doi.org/10.3390/molecules26123525.

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In this review, we present an assessment of recent advances in alkyne functionalization reactions, classified according to different classes of recyclable catalysts. In this work, we have incorporated and reviewed the activity and selectivity of recyclable catalytic systems such as polysiloxane-encapsulated novel metal nanoparticle-based catalysts, silica–copper-supported nanocatalysts, graphitic carbon-supported nanocatalysts, metal organic framework (MOF) catalysts, porous organic framework (POP) catalysts, bio-material-supported catalysts, and metal/solvent free recyclable catalysts. In addition, several alkyne functionalization reactions have been elucidated to demonstrate the success and efficiency of recyclable catalysts. In addition, this review also provides the fundamental knowledge required for utilization of green catalysts, which can combine the advantageous features of both homogeneous (catalyst modulation) and heterogeneous (catalyst recycling) catalysis.
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Querard, Pierre, Inna Perepichka, Eli Zysman-Colman, and Chao-Jun Li. "Copper-catalyzed asymmetric sp3 C–H arylation of tetrahydroisoquinoline mediated by a visible light photoredox catalyst." Beilstein Journal of Organic Chemistry 12 (December 6, 2016): 2636–43. http://dx.doi.org/10.3762/bjoc.12.260.

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This report describes a highly enantioselective oxidative sp3 C–H arylation of N-aryltetrahydroisoquinolines (THIQs) through a dual catalysis platform. The combination of the photoredox catalyst, [Ir(ppy)2(dtbbpy)]PF6, and chiral copper catalysts provide a mild and highly effective sp3 C–H asymmetric arylation of THIQs.
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Newman, R. A., J. A. Blazy, T. G. Fawcett, L. F. Whiting, and R. A. Stowe. "Use of the Dow-Developed DSC/XRD/MS in the Study of Several Model Copper-Based Catalyst Systems." Advances in X-ray Analysis 30 (1986): 493–502. http://dx.doi.org/10.1154/s0376030800021650.

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Due to the difficulty of analyzing materials at high temperatures and in reactive atmospheres, solid-state catalysts have often been developed with little knowledge of the true chemical behavior of the catalyst, except on a bulk scale. In the field of solid-state catalysis research, a great deal of time and effort is presently being spent to better characterize the chemical and physical properties which determine a particular catalyst‘s efficiency, lifetime, and selectivity. Recently, we have undertaken a study of model copper catalysts at The Dow Chemical Company in an effort to better understand the chemical and physical properties which determine the efficiency, regenerability, and lifetime of this type of solid state catalyst.
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Batool, Kiran, Rubia Shafique, Naseem Akhtar, Tahira Yaqoob, Muqaddas Jabeen, Arshad Mehmood, and Raheela Jabeen. "Synthesis and characterization of Zinc-Doped Copper Chromites by sol gel method." JOURNAL OF NANOSCOPE (JN) 2, no. 1 (June 30, 2021): 15–28. http://dx.doi.org/10.52700/jn.v2i1.23.

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Various preparation and application methods of copper chromites catalyst have recently been extensively discussed. According to all discussions, copper chromites is a versatile catalyst that not only catalyses many processes of national programmed and commercial importance, all of which are related to defense and space research, but also finds a lot of application in the most concerned worldwide, such as environmental pollution control. Copper chromites catalysts have many useful applications in the production of drugs, clean energy, and agro chemicals. Different synthesis methods are presented to prepare doped Zinc Copper chromites, demonstrating a clear understanding of the dependence of catalytic activity. This sample was created using a simple, eco-friendly sol gel method and characterized using various techniques such as EDS, SEM, UV, Raman spectroscopy, and Photoluminescence. Several parameters influence sample techniques. This sample was sintered in a furnace at 750°C for 4 hours. Zinc was successfully doped in copper chromites and emerged completely, according to EDS.
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Yun, Hafizah Abdul Halim, Ramli Mat, Tuan Amran Tuan Abdullah, Mahadhir Mohamed, and Anwar Johariand Asmadi Ali. "Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen." Applied Mechanics and Materials 699 (November 2014): 504–9. http://dx.doi.org/10.4028/www.scientific.net/amm.699.504.

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The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.
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Santa Cruz-Navarro, Dalia, Miguel Torres-Rodríguez, Mirella Gutiérrez-Arzaluz, Violeta Mugica-Álvarez, and Sibele Berenice Pergher. "Comparative Study of Cu/ZSM-5 Catalysts Synthesized by Two Ion-Exchange Methods." Crystals 12, no. 4 (April 13, 2022): 545. http://dx.doi.org/10.3390/cryst12040545.

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As catalysis is one of the pillars of green chemistry, this work aimed at continuing the development of synthesized catalysts under controlled conditions that allow the attainment of materials with the best physicochemical properties for the process for which they were designed. Based on this, the synthesis, characterization, and comparison of copper-based catalysts supported on ammonium and acidic ZSM-5-type zeolite by two ion exchange methods, liquid phase and solid state, are presented. The catalysts obtained were characterized by SEM/EDS, FTIR, XRD, and TPR to study the effect of the synthesis method on the physicochemical properties of each catalyst. The SEM/EDS results showed a homogeneous distribution of copper in the zeolite and the TPR led to determining the temperature ranges for the reduction of Cu2+ → Cu+ → Cu0. Furthermore, the X-ray results showed no modification of the structure of the zeolite after ion exchange, heat treatment, and TPR analysis.
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Thongboon, Surached, Pacharaporn Rittiron, Danusorn Kiatsaengthong, Thanaphat Chukeaw, and Anusorn Seubsai. "Propylene Epoxidation to Propylene Oxide Over RuO2, CuO, TeO2, and TiO2 Supported on Modified Mesoporous Silicas." Journal of Nanoscience and Nanotechnology 20, no. 6 (June 1, 2020): 3466–77. http://dx.doi.org/10.1166/jnn.2020.17408.

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Direct gas phase epoxidation of propylene to propylene oxide (PO) using O2 is a challenging problem in catalysis research. Silica-supported ruthenium-copper-based catalysts have been recently reported to be promising for propylene epoxidation. In this work, mesoporous silica supports modified with RuO2, CuO, and TeO2 with and without TiO2 were investigated for propylene epoxidation to PO. The prepared catalysts were divided into two groups. The first group consisted of mesoporous silica supports modified with RuO2, CuO, and TeO2, and the second group consisted of the same components as the first group but adding TiO2. The prepared supports and catalysts were characterized using BET surface area analysis and other advanced instrument techniques. It was found that the catalyst made with RuO2 and TeO2 impregnated onto porous silica modified with CuO and TiO2 (denoted as RuTe/CuTiSi) exhibited an excellent PO formation of 344 gPO h−1 kg−1cat, which was superior to that of the other prepared catalysts. Moreover, the addition of TiO2 into the catalyst greatly improved the PO formation rate and the arrangement of active components in the catalyst and strongly influenced catalytic performance.
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Din, Israf Ud, Maizatul Shima Shaharun, Duvvuri Subbarao, and A. Naeem. "Synthesis, Characterization and Activity Pattern of Carbon Nanofibres Based Cu-ZrO2 Catalyst in the Hydrogenation of Carbon Dioxide to Methanol." Advanced Materials Research 925 (April 2014): 349–53. http://dx.doi.org/10.4028/www.scientific.net/amr.925.349.

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Carbon nanofibers based Cu-ZrO2 catalysts (Cu-ZrO2/CNF) were synthesized by deposition precipitation method. Carbon nanofibers of herringbone type were used as a catalyst support. Before using as catalyst support, carbon nanofibers were oxidized to (CNF-O) with 10 % (v/v) nitric acid solution. A series of catalyst with various copper loadings of 10, 15 and 20 wt% were synthesized. X-ray diffraction (XRD) study revealed that degree of crystallization of catalyst increase with increasing the concentration of copper content in the catalyst. BET studies showed higher surface area for low loading of copper. Temperature-Programmed Reduction (TPR) analyses concluded good interaction of catalyst particles with higher loading of copper. The performance of Cu-ZrO2/CNF catalysts in hydrogenation of CO2 reaction was studied in slurry-typed reactor at 443 K, 30 bar and H2: CO2 ratio of 3:1. The highest yield of methanol was achieved using the 20 wt% copper loading.
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Nesterova, Oksana V., Armando J. L. Pombeiro, and Dmytro S. Nesterov. "Tetranuclear Copper Complexes with Bulky Aminoalcohol Ligands as Catalysts for Oxidative Phenoxazinone Synthase-like Coupling of Aminophenol: A Combined Experimental and Theoretical Study." Catalysts 12, no. 11 (November 10, 2022): 1408. http://dx.doi.org/10.3390/catal12111408.

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The new copper(II) complexes [Cu4(pa)4(Bae)4]·H2O (1) and [Cu4(eba)4(Buae)4]·H2O (2) (Hpa = propionic acid, HBae = 2-benzylaminoethanol, Heba = 2-ethylbutyric acid and HBuae = 2-butylaminoethanol) were synthesizsed by the interaction of a copper salt with a methanol solution of the respective ligands. The single-crystal X-ray diffraction analysis reveals that both compounds have a {Cu4(μ3-O)4} cubane-like core. Both compounds show pronounced phenoxazinone synthase-like activity towards the aerobic oxidation of o-aminophenol to phenoxazinone chromophore, with the maximum initial rates W0 up to 3.5 × 10−7 M s−1, and exhibit complex non-linear W0 vs. [catalyst]0 dependences. DFT//CCSD theoretical calculations (B3LYP/ma-def2-TZVP//DLPNO-CCSD(T)/ma-def2-TZVPP) were employed to investigate the most challenging steps of catalyst-free and copper-catalysed o-aminophenol oxidation (formation of o-aminophenoxyl radical). QTAIM analysis was used to study the key intermediates and weak interactions. Geometries and energies of intermediates and transition states were benchmarked against a series of popular DFT functionals. The results of the calculations demonstrate that a CuII–OO• copper-superoxo model catalyst decreases the calculated activation barrier from 28.7 to 19.9 kcal mol−1 for the catalyst-free and copper-catalysed abstraction of the H atom from the hydroxyl group of o-aminophenol, respectively. Finally, both complexes 1 and 2 were studied as catalysts in the amidation of cyclohexane with benzamide to give N-cyclohexyl benzamide and N-methyl benzamide employing di-tert-butyl peroxide (DTBP) as the oxidant, with a conversion of 16%, and in the oxidation of cyclohexane to cyclohexanol with aq. H2O2, with a conversion of 12%.
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Dissertations / Theses on the topic "Copper catalysi"

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Sherborne, Grant John. "Catalyst deactivation in copper-catalysed C-N cross-coupling reactions." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/17595/.

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This thesis details research into the mechanism of the copper-catalysed cross-coupling reaction, with a focus on the N-arylation of secondary amines and amides (Ullmann-Goldberg reaction). Issues limiting the application of the Ullmann-Goldberg reaction on industrial scale are uncovered and understood from a mechanistic point of view, to provide a platform for more efficient copper catalysts. In situ kinetic monitoring using 1H NMR spectroscopy is used to understand the role of each key component in the N-arylation of piperidine using a copper catalyst in a fully homogeneous system. Key roles of the amine and catalyst are observed, whilst product inhibition was found to significantly inhibit the reaction. Solvent effects are evaluated by repeating the in situ kinetic investigation in d7-DMF and d3-MeCN. The kinetic findings indicate deviation of the mechanism from the accepted literature mechanism, with a rate-limiting amine coordination proposed. Kinetic studies are also used to show the key role that the solubility of inorganic bases such as Cs2CO3 and K3PO4 play in rate-determining equilibria between copper species. Slow catalyst turnover was observed for up to 14 hours at lowered catalyst loadings, before a dramatic increase in the rate of reaction. A link between particle size, solubility and the deprotonation of the cyclic amide substrate are made, with the results having important implications on the use of inorganic bases in cross-coupling reactions. Inhibition of the reaction from inorganic side products and precipitation of copper from solution is combined with findings of a novel interaction between copper and cesium cation to give evidence for a non-innocent role of the cesium cation in copper-catalysed N-arylation. Heterogeneous catalysis is explored, where it is shown that copper precipitated from the reaction is capable of catalysis, introducing a question of a pseudo-heterogeneous mechanism and phase equilibria. A multi-edge XAFS (X-ray absorption fine structure) study is combined with laboratory experiments to uncover the activation, deactivation and reactivation pathways of an immobilised iridium transfer hydrogenation catalyst. The key role of an Ir-Cl bond is shown, where initial ligand exchange activates the catalyst, followed by further, slow ligand exchange, leading to deactivation of the catalyst.
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Boreux, Arnaud. "Development of new dual catalysis systems with gold and copper." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX053/document.

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Depuis plusieurs décennies, la catalyse par les métaux de transition est devenue un outil incontournable pour la synthèse organique. Chaque année, des milliers de publications décrivent le développement de nouvelles réactions effectuées en présence de complexes organométalliques. Le premier chapitre de ce manuscrit présente une comparaison générale de la réactivité des métaux du groupe 11 (Cu, Ag, Au), avec une attention particulière sur leur capacité à réaliser des réactions d’activation électrophile (Au) ou des transferts de nucléophiles (Cu). Des exemples représentatifs sont donnés pour illustrer ces concepts. Dans la seconde partie, la synthèse d’allènes et d’énones trifluorométhylés par catalyse à l’or(I) est détaillée. Une méthode générale de préparation d’allènes-CF3 a été développée par un transfert d’hydrure-1,5 induit par un complexe d’or(I). Les limites de la méthode ainsi que certaines applications des produits sont décrites. Dans la même idée, un réarrangement-[3,3] d’acétates propargylique catalysé par l’or(I) a été appliqué à la synthèse d’énones-CF3. L’incorporation de cette méthode dans un processus monotope avec une réaction de Diels-Alder est également présentée. La troisième partie est centrée sur les réactions de borofonctionnalisation d’allènes catalysées par le cuivre(I). Les récents développements de ce domaine sont passés en revue, et notre contribution à ce sujet est détaillée. Enfin, un travail préliminaire sur l’élaboration d’un processus monotope impliquant une catalyse coopérative cuivre(I)/or(I) est présenté
During the last decades, transition metal catalysis has become an essential tool in organic synthesis. Each year, thousands of publications report the development of new reactions mediated by metal complexes. This manuscript depicts our contribution to this field. The first chapter presents a general comparison of the reactivity of coinage metals (Cu, Ag, Au) complexes in catalysis, with a special focus on their ability to perform electrophilic activation (Au) or nucleophilic transfer (Cu) reactions. Representative examples are given to illustrate these concepts. In the second part of the manuscript, the synthesis of trifluoromethylated allenes and enones by gold(I) catalysis is reported. A general method for the preparation of CF3-allenes has been developed based on a gold(I)-mediated 1,5-hydride shift. The scope and limitations of the method, as well as some subsequent transformations of the products are described. Using similar substrates, a gold(I)-catalyzed [3,3]-acetate rearrangement was applied to the preparation of CF3-enones. The employment of this method into a one-pot procedure involving a subsequent Diels-Alder reaction is also reported. The third part focuses on the copper(I)-catalyzed borofunctionalization of allenes. The recent reports from the literature are reviewed, and our contributions to this area of research are described through the study of a new copper(I)-catalyzed allene boroacylation method. Finally, preliminary results on the elaboration of a copper(I)/gold(I) catalytic one-pot process are presented
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Emera, Flory. "Method development for copper dispersion evaluation and copper-based catalysts characterization." Thesis, Uppsala universitet, Strukturkemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-206922.

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N2O chemisorption technique for copper dispersion determination was developed and optimized for accurate and reproducible results. With this technique, the bulk oxidation of pre-reduced catalyst can be prevented by N2O decomposition at low temperature (30oC). Only surface copper atoms are oxidized. The amount of freshly oxidized surface coppers is determined from H2-back-titration of fixed oxygen.The impact of temperature and time of exposure during oxidation was studied. Measurements made at higher temperature (60oC) resulted in overestimation of copper dispersion due to oxygen diffusion into the bulk and sub-layers. Much longer exposure time may also have an impact on copper dispersion estimation.For accurate results and good precision, it is recommended to work under mild conditions (isothermal oxidation at 30oC for 45 min.The developed method was successfully applied to fresh and spent catalyst. As expected, the copper dispersion for fresh catalyst was significantly higher than copper dispersion for spent catalyst.
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Lonca, Geoffroy. "Development of new reactions of organic synthesis catalyzed by gold and copper." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX057/document.

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Cette thèse décrit le développement de nouvelles méthodes de catalyse à l’or et au cuivre pour la synthèse de composés hétérocycliques et de produits trifluorométhylés.Dans un premier temps, une synthèse d’allènes trifluorométhylés par catalyse à l’or a été développée, dont l’étape clé est un transfert d’hydrure 1,5. Cette méthode donne accès de manière efficace et sélective à une large gamme d’allène perfluoroalkylés dont le potentiel synthétique a également été démontré.Le pouvoir catalytique de l’or a alors été utilisé dans une synthèse de 2H-1,3-oxazines reposant sur une cyclisation de type 6-endo d’azido alcynes. Cette méthode donne accès dans des conditions très douces à une gamme sans précédent d’oxazines polysubstituées avec d’excellents rendements.Dans un dernier temps, une méthode d’hydrofonctionnalisation radicalaire d’alcènols catalysée au cuivre. La stratégie impliquée repose sur une abstraction d’hydrogène 1,5, dans laquelle un groupement benzyloxy joue le rôle de donneur d’hydrogène
This manuscript presents the development of gold- and copper-catalyzed methods for the synthesis of heterocyclic compounds and trifluoromethylated products.Firstly, a gold-catalyzed synthesis of trifluoromethyl allenes was developed, relying on a 1,5 hydride shift. This method allows to access, in a very efficient and selective way, a large range of perfluoroalkylated allenes, of which the synthetic potential was also demonstrated.Afterwards, the catalytic power of gold was then used in a synthesis of 2H-1,3-oxazines, relying on a 6-endo type cyclization of azide-yne substrates. This methods allows to access, in very mild condition, an unprecedently large range of polysubstituted oxazines in excellent yields.Finally, a method for the copper-catalyzed radical hydrofunctionalization of alkenols was developed. The strategy involved relies on a 1,5 hydrogen abstraction, in which a benzyloxy moiety plays the role of the hydrogen donor
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Mikus, Malte Sebastian. "Mechanistic Studies, Catalyst Development, and Reaction Design in Olefin Metathesis:." Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108382.

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Thesis advisor: Amir H. Hoveyda
Chapter 1. Exploring Ligand Effects in Ruthenium Dithiolate Carbene Complexes. Ruthenium dithiolate metathesis catalysts discovered in the Hoveyda group have been a valuable addition to the field of olefin metathesis. While the catalyst shows unique selectivity and reactivity, quantifying and mapping key interactions in the catalyst framework to elucidate and explain causes is difficult. We, therefore, decided to use the neutral chelating or monodentate ligand, controlling initiation, as a structural probe. By altering its properties and observing changes in the catalyst, we sought to deepen our understanding of these complexes. We established a trans influence series with over 20 catalysts and correlated the impact on catalyst initiation. Further, we show that in the case of strongly σ-donating and π-accepting ligands such as phosphites and isonitriles, the complex exhibits fluxional behavior. The catalysts ground state is elevated to such a degree that thiolate Ruthenium bonds become labile and rapidly exchange. While Ruthenium dithiolate catalysts were readily applied to metathesis polymerization, their use in the synthesis of small molecules was initially less forthcoming. Specifically, reactions involving terminal olefins lead to rapid catalyst deactivation and only low conversion. We were able to determine that the potential energy stored in the trans-influence between the thiolate ligand and the NHC can be released in a sulfur shift to reactive Ruthenium methylidene species. Since methylidenes are formed by reaction with terminal olefins, use of an excess of internal olefins can prevent their formation. Chapter 2. Harnessing Catalyst Fluxionality in Olefin Metathesis. Depending on its use, material requirements can vary significantly. Materials that can easily be adapted to a given application, for example by varying tensile strength, melting point or solubility, are desirable. Controlling the polymers tacticity (the adjacent stereocenters in a polymer chain) is a straight forward way to achieve just that. Ru dithiolate catalysts should give highly syndiotactic polymers due to their single stereocenter undergoing inversion during every metathesis step. The fluxional nature of the catalyst allows for control of polymer tacticity from 50% (atactic) to ≥95% syndiotacticity by changing monomer concentration. We determined the factors which are responsible for fluxionality and synthesized complexes that give either high or low levels of tacticity over a broader range of monomer concentration. Chapter 3. Harnessing Catalyst Fluxionality in Olefin Metathesis. The importance of fluorine-containing molecules is hard to understate, keeping in mind the surge of new methodologies for their synthesis and the medical breakthroughs they enable. However, efficient and practical syntheses of stereodefined alkenyl fluorides are rare. In this context, we have developed enantioselective boryl allylic substitution of allylic fluorides, which yield enantioenriched γ-alkenyl fluoride substituted allyl boronate esters. The reaction is catalyzed by Cu-based catalysts that are prepared in-situ and delivered as products with high yield and enantioselectivity. Mechanistic inquiry shows the reaction is not a concerted allylic substitution. An intermediate Cu alkyl complex is formed after the Cu boron addition is made to the double bond, which only slowly undergoes β-fluorine elimination in the presence of a Lewis acid
Thesis (PhD) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Kydd, Richard Berwick Chemical Sciences &amp Engineering Faculty of Engineering UNSW. "Synthesis and characterisation of gold and copper oxidation catalysts." Awarded by:University of New South Wales. Chemical Sciences & Engineering, 2009. http://handle.unsw.edu.au/1959.4/44549.

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In this work, Gold and Copper oxidation catalysts supported on a range of metal oxides were synthesised via 2 previously uninvestigated preparation methods. In the first chapter, Gold nanoparticle catalysts were deposited onto TiO2, CeO2 and ZrO2 nanoparticles via the non-aqueous Modified Photodeposition procedure. This method was found to produce smaller Gold particle sizes following intrinsic excitation of the support than the conventional aqueous phase method, with surface physisorbed water apparently acting as the sacrificial reductant. The as prepared catalysts were drastically more active than those prepared by the conventional method and under standardised tests were directly comparable to those prepared by the Deposition Precipitation Method. The second part of the work, explored the preparation of metal oxide supported Copper catalysts via the Flame Spray Pyrolysis process. CO Oxidation tests established the following order of activity for 4wt% Cu loaded on the various supports: Cu-CeO2 > Cu-TiO2 > Cu-ZrO2 > Cu-Al2O3 > Cu-SiO2. CO-TPD studies found that more active materials tended to adsorbed more CO and reacted higher proportions of this with lattice oxygen to form CO2 at lower temperatures. The addition of Cu to each metal oxide surface was found to induce lengthening of the average Metal-Oxygen bond length, with higher electron density on surface O. This phenomenum is proposed as being responsible for the widely reported ???synergistic effect??? reported for similar Cu catalysts. Cu-CeO2 (0-12wt%) catalysts were tested in the Preferential CO Oxidation (COPROX) reaction. Increasing Cu content, varied the Cu morphology from monomers, through to dimers and ultimately CuO crystallites. DFT simulations of the Cu dimer structure revealed higher levels of bonding ionicity in this morphology, relative to the monomeric structure. This coincided with higher levels of activity, reinforcing the earlier finding that highly ionic bonds are conducive to higher levels of activity. High levels of activity and selectivity were maintained until approximately 423 K. Surface redox properties of the 4wt% Cu-CeO2 catalyst were assessed using temperature-programmed reduction (CO, H2) and desorption (CO) experiments, as well as in situ and phase-resolved infrared spectroscopy to study the transition to nonselective conditions. For the first time, it was demonstrated that CO and H2 react at identical surface sites, with CO2 formation proceeding simultaneously via three distinct Cux+-CO carbonyl species. Under non-selective conditions, a gradual red-shift and loss of intensity in the carbonyl peak was observed, indicating reduction of Cu+ to Cu0 and the onset of an alternate non-selective redox-type oxidation mechanism. These results for Cu-CeO2 suggest that improved low temperature catalytic activity will only be achieved at the expense of reduced high temperature selectivity and vice versa. The final section of work explored the use of Cu-based catalysts for the low temperature oxidation of Acetaldehyde (ACA). Based on this work, it is concluded that the ACA oxidation activity of these materials is determined by two main factors: the basicity of the metal oxide support (and its subsequent ability to convert ACA to carboxylates) and the availability of surface oxygen during acetate decomposition. It is proposed that a high concentration of reducible sites (either by Cu addition or naturally occurring on CeO2) accelerates the activation and provision of oxygen and also potentially provides sites for the stabilization of methoxy intermediates resulting from the acetate decomposition.
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Goodby, Brian Edward. "Characterization of copper/zinc-oxide catalysts for methanol reformation." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184479.

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The research presented in this dissertation involved characterization of the Cu/ZnO solid catalyst system as applied to methanol/steam reformation. Thermogravimetry was used to investigate in-lab synthesized samples and a commercial product G66B (Cu/ZnO 33/67 wt. %). The 33% Cu sample contained Cu ions in the ZnO matrix. This phase required the highest temperatures (400°C) for H₂ reduction. The 50% Cu sample reduced at a lower temperature (220°C) but its complete reduction required the same maximum temperature. The higher temperature process was similar to the 33% case, while the lower one was due to the reduction of a amorphous CuO phase. The 66% Cu sample reduced in a fairly narrow low temperature (270°C) range. Therefore, its CuO phase has a amorphous structure. G55B reduced at lower temperatures than the in-lab samples. This difference is possibly due to different synthetic procedures used in the production of G66B and the in-lab samples. The CuO phase of G66B appears to be amorphous and well dispersed. Raman spectroscopy was used to identify the crystal phases of these solids. The complexity of the initial precipitate was monitored versus the Cu/Zn ratio of the system. The nature of the phases present under reduction conditions was determined. This information has provided insight into the active phases involved in methanol reformation. The role of the solids lattice oxygen was determined. The reaction was carried out on labelled ¹⁸O-containing Cu/ZnO. Incorporation of ¹⁸O into both CO₂ and H₂O clearly indicates the involvement of these oxygens in the reaction. Observation of C¹⁸O¹⁸O indicates that the C-O bond in methanol does not remain intact. XPS was used to determine the effects of oxidation, reduction, and reaction on the Cu component of G66B. Upon oxidation all Cu exists as Cu⁺². The catalyst always contains Cu⁺¹ and Cuᵒ after H₂ reduction. After methanol/steam reformation with a 50/50 vol% mxiture, all Cu is reduced to Cuᵒ. Changes in the Cu/Zn ratio of the surface are interpreted in terms of changes in surface morphology.
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Hautier, Alexandre. "Synthesis and characterization of copper-peptide systems for oxidation catalysis." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0758.

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La catalyse permet de réaliser des transformations efficaces à un coût énergétique plus faible qu'avec des réactions non catalysées. Le développement d’un catalyseur peut souvent être inspiré par la Nature qui parvient à réaliser des transformations chimiques difficiles avec de hauts rendements et une grande sélectivité et ce en milieu aqueux dans des conditions douces. Par exemple, les protéines dépendantes du cuivre peuvent oxyder une large gamme de substrats. Inspirés par les systèmes biologiques, les metallopeptides ont récemment émergés en tant que plate-forme fiable pour développer de nouveaux catalyseurs grâce à leur facilité d’accès, de maniement et d’affinage de leurs propriétés. Dans cette thèse, nous décrivons la synthèse d’une famille de décapeptides bio-inspirés, qui contiennent des résidus His et Asp permettant de coordiner des ions métalliques. Les données indiquent que tous les peptides se lient au cuivre et qu’ils forment, à un pH proche de la neutralité, une espèce cuivre (II) majoritaire, similaire entre tous les peptides. Dans ces complexes, les peptides lient le cuivre (II) par les chaines latérales des résidus His et Asp. Pour finir, la capacité de ces systèmes ainsi que des complexes cuivre (II)-amyloid-β à catalyser des transformations oxydantes en solution aqueuse en utilisant H2O2 comme oxydants a été évaluée. Cette étude révèle que i) la structure des peptides à un impact sur les rendements catalytiques et sur l’obtention d’excès énantiomérique, et que ii) les complexes cuivre (II)-amyloid-β sont moins performants que nos systèmes cuivre (II)-peptide
Catalysis gives access to efficient transformations at a lower cost in energy and generally offers possibilities to reduce or eliminate the need for and the generation of hazardous compounds . The development of a catalyst is often inspired by Nature that performs challenging chemical transformations with high rates and high selectivity under mild conditions and aqueous media. For example, copper dependent proteins can react to oxidize a broad range of substrates. Inspired by biological systems, metallopeptides have recently emerged as reliable platforms to evolve new catalysts because they are chemically accessible, easy to handle and fine-tune.In this work we synthetized a family of bioinspired decapeptides containing His and Asp residues as metal ion coordinating amino acids. Their copper coordination properties were studied using pH potentiometry, and different spectroscopic techniques (UV-Vis, CD, EPR, NMR). The data indicates that all the peptides bind copper and form similar major copper(II) species at a pH close to neutrality where copper (II) is coordinated by the side-chains of His and Asp residues. Finally, the capabilities of these metallopeptides to perform a variety of oxidative transformations in aqueous solution at room temperature, using H2O2 as the oxidant were evaluated in parallel with that of amyloid-β peptides copper (II) complexes. This study revealed that i) the scaffold of the designed peptides had an impact on the catalytic efficiencies and enantiomeric excess and ii) the amyloid-β peptides copper (II) complexes are less active than our designed copper(II) peptide systems
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9

Calogero, F. "NEW SYNTHETIC PROCESSES FOR THE APIS INDUSTRIAL PRODUCTION: THE CASE OF SILODOSIN." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/243613.

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This thesis is focused on the development of new synthetic processes for the production of already known Active Pharmaceutical Ingredients (APIs). The research work was performed in the laboratories of Dipharma Francis srl, a company which operates in the generic drug market. The launch of the generic version of a drug in the market often leads to lowering of product prices for both the branded product and the generic ones. For this reason, the process adopted to produce an API has to be innovative, efficient, safe and, of course, cheaper than the existing ones, in order to be competitive in the market. During my Ph.D. I worked on the synthesis of some APIs, in particular here I report the feasibility and development studies of an alternative process to produce silodosin. Silodosin is an API used as a treatment for the symptoms of Benign Prostatic Hyperplasia (BPH). In order to establish the synthetic strategy and to outline our freedom to operate, an accurate survey of the whole patent literature about silodosin has been done. During the feasibility study several synthetic approaches have been tried in order to functionalise indoline at positions 5 and 7. A copper(I) catalysed C-arylation reaction and a regioselective electrophilic aromatic substitution revealed to be the best choices to introduce respectively substituents in position 5 and 7 of indoline. The synthesis continued with a diastereoselective reductive amination which after crystallisation yielded optically pure amine intermediate that is the key intermediate for the synthesis of silodosin and ended converting amine intermediate into Silodosin using already reported procedures. Our new process to prepare silodosin starting from commercially available and cheap indoline consists of 11 steps. The whole synthetic route has been performed in gram scale using only 4 purifications of key intermediates. Silodosin has been finally obtained in a 10% overall yield, with a purity greater than 99% measured by HPLC and an optical purity greater than 99% measured by HPLC on chiral stationary phase.
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Ali, H. Saad Moh'd. "Selective catalytic oxidation of ammonia using copper and iron supported on ZSM-5 catalysts." Thesis, University of Manchester, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525661.

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Books on the topic "Copper catalysi"

1

Bagri, R. Structure sensitivity in supported copper catalyst. Manchester: UMIST, 1995.

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Rajaie, R. Torbati. Structure sensitivity in supported copper catalysts. Manchester: UMIST, 1996.

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Gould, L. J. Structure sensitivity in supported copper catalysts. Manchester: UMIST, 1994.

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Zemicael, F. W. Structure sensitivity of model copper catalysts and Cu/ZnO/Al2O3 methanol synthesis and low temperature shift catalysis. Manchester: UMIST, 1996.

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Kubota, Koji. Synthesis of Functionalized Organoboron Compounds Through Copper(I) Catalysis. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-4935-4.

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1945-, Floris Giovanni, and Mondovì Bruno, eds. Copper amine oxidases: Structures, catalytic mechanisms, and role in pathophysiology. Boca Raton: Taylor & Francis, 2009.

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Shahani, C. J. Effect of some deacidificaiton agents on copper-catalyzed degradation of paper. Washington, D.C: Preservation Directorate, Library of Congress, 1995.

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Shahani, Chandru J. Effect of some deacidification agents on copper-catalyzed degradation of paper. Washington, D.C: Preservation Directorate, Library of Congress, 1995.

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Anilkumar, Gopinathan, and Salim Saranya. Copper Catalysis in Organic Synthesis. Wiley & Sons, Limited, John, 2020.

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Anilkumar, Gopinathan, and Salim Saranya, eds. Copper Catalysis in Organic Synthesis. Wiley, 2020. http://dx.doi.org/10.1002/9783527826445.

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Book chapters on the topic "Copper catalysi"

1

Feringa, Ben L. "Oxidation Catalysis; A Dinuclear Approach." In Bioinorganic Chemistry of Copper, 306–24. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-6875-5_24.

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Cant, N. W., B. Sexton, D. L. Trimm, and M. S. Wainwright. "Supported Copper Catalysts: Surface Studies and Catalytic Performance." In Springer Proceedings in Physics, 290–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-84933-6_23.

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Gorzka, Zbigniew, Marek Kaźmierczak, and Andrzej Żarczyński. "Catalytic Oxidation of 1,2-Dichloropropane on Copper-Zinc Catalyst." In Chemistry for the Protection of the Environment 3, 143–47. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4757-9664-3_17.

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Brown, E. S., and B. D. Dombek. "By Copper Catalysts." In Inorganic Reactions and Methods, 266–67. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145319.ch88.

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Kunz, Klaus, and Norbert Lui. "Process Chemistry and Copper Catalysis." In Copper-Mediated Cross-Coupling Reactions, 725–43. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118690659.ch19.

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Stibrany, Robert T. "Copper-Based Olefin Polymerization Catalysts: High-Pressure19F NMR Catalyst Probe." In ACS Symposium Series, 210–21. Washington, DC: American Chemical Society, 2003. http://dx.doi.org/10.1021/bk-2003-0857.ch015.

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Likhtenshtein, Gertz I. "Copper-Containing Enzymes." In Chemical Physics of Redox Metalloenzyme Catalysis, 187–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73100-6_8.

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Maria, Anna, and Raspolli Galletti. "Copper Catalysts for Olefin Polymerization." In Handbook of Transition Metal Polymerization Catalysts, 497–511. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2010. http://dx.doi.org/10.1002/9780470504437.ch14.

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Stibrany, Robert T., Abhimanyu O. Patil, and Stephen Zushma. "Copper-Based Olefin Polymerization Catalysts." In ACS Symposium Series, 194–209. Washington, DC: American Chemical Society, 2003. http://dx.doi.org/10.1021/bk-2003-0857.ch014.

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Finn, M. G., and Valery V. Fokin. "Copper-Catalyzed Azide-Alkyne Cycloaddition (CuAAC)." In Catalysis without Precious Metals, 235–60. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527631582.ch10.

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Conference papers on the topic "Copper catalysi"

1

Patel, Sanjay, and K. K. Pant. "Hydrogen Production for PEM Fuel Cells via Oxidative Steam Reforming of Methanol Using Cu-Al Catalysts Modified With Ce and Cr." In ASME 2006 4th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2006. http://dx.doi.org/10.1115/fuelcell2006-97209.

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The performance of Cu-Ce-Al-oxide and Cu-Cr-Al-oxide catalysts of varying compositions prepared by co-precipitation method was evaluated for the PEM fuel cell grade hydrogen production via oxidative steam reforming of methanol (OSRM). The limitations of partial oxidation and steam reforming of methanol for the hydrogen production for PEM fuel cell could be overcome using OSRM and can be performed auto-thermally with idealized reaction stoichiomatry. Catalysts surface area and pore volume were determined using N2 adsorption-desorption method. The final elemental compositions were determined using atomic absorption spectroscopy. Crystalline phases of catalyst samples were determined by X-ray diffraction (XRD) technique. Temperature programmed reduction (TPR) demonstrated that the incorporation of Ce improved the copper reducibility significantly compared to Cr promoter. The OSRM was carried out in a fixed bed catalytic reactor. Reaction temperature, contact-time (W/F) and oxygen to methanol (O/M) molar ratio varied from 200–300°C, 3–21 kgcat s mol−1 and 0–0.5 respectively. The steam to methanol (S/M) molar ratio = 1.4 and pressure = 1 atm were kept constant. Catalyst Cu-Ce-Al:30-10-60 exhibited 100% methanol conversion and 152 mmol s−1 kgcat−1 hydrogen production rate at 300°C with carbon monoxide formation as low as 1300 ppm, which reduces the load on preferential oxidation of CO to CO2 (PROX) significantly before feeding the hydrogen rich stream to the PEM fuel cell as a feed. The higher catalytic performance of Ce containing catalysts was attributed to the improved Cu reducibility, higher surface area, and better copper dispersion. Reaction parameters were optimized in order to maximize the hydrogen production and to keep the CO formation as low as possible. The time-on-stream stability test showed that the Cu-Ce-Al-oxide catalysts subjected to a moderate deactivation compared to Cu-Cr-Al-oxide catalysts. The amount of carbon deposited onto the catalysts was determined using TG/DTA thermogravimetric analyzer. C1s spectra were obtained by surface analysis of post reaction catalysts using X-ray photoelectron spectroscopy (XPS) to investigate the nature of coke deposited.
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PARK, S. J., B. J. KIM, and Y. S. JANG. "CATALYTIC REDUCTION MECHANISM OF NITRIC OXIDE OVER ACFs/COPPER CATALYST." In Proceedings of the Third Pacific Basin Conference. WORLD SCIENTIFIC, 2003. http://dx.doi.org/10.1142/9789812704320_0088.

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Das, Randip K., B. B. Ghosh, Souvik Bhattacharyya, and Maya DuttaGupta. "Catalytic Control of SI Engine Emissions Over Ion-Exchanged X-Zeolites." In ASME 1997 Turbo Asia Conference. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-aa-077.

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Three catalysts based on X-zeolite have been developed by exchanging its Na+ ion with Copper, Iron and Nickel metal ions and tested in a SI engine exhaust for a wide range of exhaust and operating conditions. Of the three catalysts, the Cu-X catalyst exhibits the best NOx and CO conversion performance while Ni-X shows slightly better performance compared to the Fe-X catalyst at any catalyst temperature. Unlike noble metals, the doped X-zeolite catalysts, studied here, exhibit significant NOx reduction for a wide λ range and exhibit a slow rate of decrease with increase in λ ratio. Back pressure developed across the catalyst bed is found to be well-afford able and power loss due to back pressure is only 0.216% at space velocity of 52500 /h. During 30 hours of testing of each catalyst, no significant deactivation of any catalyst is observed.
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Walke, P. V., and N. V. Deshpande. "Testing of New Catalyst for Compression Ignition Engine Exhaust Treatment." In ASME 2005 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/icef2005-1277.

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Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO2) were used as the catalyst. Copper spacer is used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination of the exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas recirculation has proved to be effective in reducing NOx.
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Walke, P. V., N. V. Deshpande, and L. P. Daddamwar. "Operating Parameters of Catalysts With Catalytic Converter for Compression Ignition Engine." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82974.

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Testing of catalytic converter with exhaust gas re-circulation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx.
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Walke, P. V., N. V. Deshpande, and A. K. Mahalle. "Performance and Emission Characteristics of a Diesel Engine Using Catalysts With Exhaust Gas Ricirculation." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14484.

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Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx.
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7

Muthiya, S. Jenoris, Induja Saravanan, Gajalakshmi Balachandran, and 1Lt P. S. Raghavan. "Experimental Investigation in Diesel Oxidation Catalyst by Developing a Novel Catalytic Materials for the Control of HC, CO and Smoke Emissions." In International Conference on Advances in Design, Materials, Manufacturing and Surface Engineering for Mobility. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2020. http://dx.doi.org/10.4271/2020-28-0458.

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<div class="section abstract"><div class="htmlview paragraph">Diesel-powered engines are used worldwide for efficient transportation and stationary power generation. The significant drawback of a diesel engine is its harmful emissions. The stringent emission norms enforced by the different organization demands effective catalyst system to control the gaseous emissions. Diesel oxidation catalysts are the extensively used technique for diesel engines to control HC and CO emissions. Currently the catalyst in the diesel oxidation system employs precious metals such as Pt/Pd/Rh to reduce the emissions and makes the DOC system expensive. This paper presents a cost-effective catalyst prepared to employ non-noble mixed oxides of copper and nickel supported on non-conventional support (i.e.) ceria doped calcium borophosphates (Ce-SCaPB). Initially, ceramic beads (5mm X 5mm) were coated with (Ce-SCaPB) support material. Secondly, the copper and nickel salts were deposited on the Ce-SCaPB coated ceramic beads and subsequently reduced and calcined. The crystallinity and phase formation was studied using XRD technique and SEM image showed particle size ranging between 40 - 50 nm. These catalyst coated beads were loaded into the fabricated DOC reactor and was retrofitted into the tailpipe of the engine exhaust. The experimental emission testing was carried out in a single-cylinder diesel engine coupled with eddy current dynamometer. In engine testing, catalytic material are tested individually to evaluate his reduction percentage. The engine test was conducted under different engine loads (0-100%) and the emission readings were taken for each load. Uncertainty analysis is calculated for the results and the results showed a higher reduction in CO, HC and smoke emissions.</div></div>
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Wang, Jung-Hui, and Chuin-Tih Yeh. "Washcoating Copper Catalyst With Various Metal Oxides Sol Onto Microchannel Reactor for Steam Reforming of Methanol." In ASME 2010 8th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2010. http://dx.doi.org/10.1115/fuelcell2010-33305.

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Washcoating copper catalyst in the micro-channel reactor for steam reforming of methanol (SRM) is advantageous to get high ratio of surface area to volume. Catalyst was coated using brushing method by making slurry with different metal oxides sol as binder (ceria, zirconia and yttria). In the preparation of catalyst slurry, the solid content, ratio of catalyst to binder, pH value and solvent were investigated. The adhesion of catalyst can be compared by estimating the weight loses of washcoating layer after 130W sonication for 30 min. The crystallite, morphology, reduction temperature and chemical environment of catalysts can be characterized by XRD, SEM, TPR and OTPR. The catalyst coated with various metal oxides sol mixing water/ethanol solvent with a specific solid content and catalyst/binder ratio in the neutral solution exhibits a good adherence with the substrate. The performance of fabricated micro-reformer is investigated in the temperature range 150–300 °C. In GHSV = 60,000 h−1, the conversion reaches 80% at 210 °C, and it corresponded to the generating of hydrogen for power output of 2 W assuming a 50% fuel cell operating efficiency. Furthermore, the fabrication of microchannels reactor connecting high temperature PEMFC is investigated.
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Krishna, M. V. S. Murali, Ch Indira Priyadarsini, P. Ushasri, P. V. K. Murthy, and D. Baswaraju. "Comparative Studies on Performance and Emissions of Two Stroke and Four Stroke Copper Coated Spark Ignition Engines With Methanol Blended Gasoline." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62264.

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Investigations were carried out to evaluate the performance of two stroke and four stroke of single cylinder, spark ignition (SI) engines having copper coated engine [CCE, copper-(thickness, 300 μ)] coated on piston crown and inner side of cylinder head] provided with catalytic converter with sponge iron as catalyst with methanol blended gasoline (80% gasoline and 20% methanol by volume) and compared with conventional engine (CE) with pure gasoline operation. Performance parameters — brake thermal efficiency (BTE), exhaust gas temperature (EGT), volumetric efficiency and exhaust emissions of carbon monoxide (CO) and un-burnt hydrocarbon (UBHC) were determined with different values of brake mean effective pressure (BMEP) of the engine and compared with one over the other of two stroke and four stroke SI engine with different versions of the engine. Formaldehyde and acetaldehyde emissions were measured by 2, 4 dinitrophenyl hydrazine (2,4 DNPH) method at peak load operation of CE and CCE of two-stroke and four-stroke SI engine. The engine was provided with catalytic converter with sponge iron as catalyst. There was provision for injection of air into the catalytic converter. Brake thermal efficiency increased with methanol blended gasoline with both versions of the engine. CCE showed improvement in the performance when compared with CE with both test fuels. Four-stroke engine decreased exhaust emissions effectively in comparison with two-stroke engine with both versions of the engine. Catalytic converter with air injection significantly reduced exhaust emissions with different test fuels on both configurations of the engine.
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Krishna, Maddali V. S. Murali, Ch Indira Priyadarsini, Y. Nagini, S. Naga Sarada, P. Usha Sri, and D. Srikanth. "Effect of Spark Ignition Timing on Copper Coated Spark Ignition Engine With Alcohol Blended Gasoline With Catalytic Converter." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50159.

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This paper reports performance evaluation of four–stroke, single–cylinder, water cooled, variable compression ratio (3–9), variable speed (2200–3000 rpm) spark ignition engine with brake power of 2.2 kW at a speed of 3000 rpm with copper coated combustion chamber (CCE) [copper-(thickness, 300 μ) was coated on piston crown, inner side of liner and cylinder head] with alcohol blended gasoline [20% methanol with 80% gasoline; 20% of ethanol with 80% of gasoline by volume) with varied spark ignition timing provided with catalytic converter with sponge iron as catalyst along with air injection and compared with engine with conventional combustion chamber (CE) with gasoline operation. Performance parameters and exhaust emissions (CO and UBHC) were evaluated at full load operation of the engine. Aldehydes (formaldehyde and acetaldehyde) were measured by wet method of 2,4, dinitrophenyle method at full load operation of the engine. Alcohol blended gasoline operation improved performance and reduced CO and UBHC emissions when compared with gasoline operation with both versions of the combustion chamber. At recommended and injection timing, CCE with test fuels improved performance and reduced pollution levels, when compared with CE. Catalytic converter with sponge iron as catalyst along with air injection significantly reduced pollutants with test fuels.
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Reports on the topic "Copper catalysi"

1

Owens, L., T. M. Tillotson, and L. M. Hair. Characterization of vanadium/silica and copper/silica aerogel catalysts. Office of Scientific and Technical Information (OSTI), September 1995. http://dx.doi.org/10.2172/212472.

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Choi, A. S. DWPF coupled feed flowsheet material balance with batch one sludge and copper nitrate catalyst. Office of Scientific and Technical Information (OSTI), September 1993. http://dx.doi.org/10.2172/10124416.

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Spassova, Ivanka, Nataliya Stoeva, Petya Georgieva, Mariana Khristova, and Dimitar Mehandjiev. Copper Catalysts Supported on Alumina-Carbon Composites in NO Reduction with CO. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, August 2020. http://dx.doi.org/10.7546/crabs.2020.08.04.

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Jernigan, Glenn Geoffrey. Carbon monoxide oxidation over three different states of copper: Development of a model metal oxide catalyst. Office of Scientific and Technical Information (OSTI), October 1994. http://dx.doi.org/10.2172/10107712.

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T. Brent Gunnoe. Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems. Office of Scientific and Technical Information (OSTI), February 2011. http://dx.doi.org/10.2172/1005126.

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Chefetz, Benny, Baoshan Xing, Leor Eshed-Williams, Tamara Polubesova, and Jason Unrine. DOM affected behavior of manufactured nanoparticles in soil-plant system. United States Department of Agriculture, January 2016. http://dx.doi.org/10.32747/2016.7604286.bard.

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The overall goal of this project was to elucidate the role of dissolved organic matter (DOM) in soil retention, bioavailability and plant uptake of silver and cerium oxide NPs. The environmental risks of manufactured nanoparticles (NPs) are attracting increasing attention from both industrial and scientific communities. These NPs have shown to be taken-up, translocated and bio- accumulated in plant edible parts. However, very little is known about the behavior of NPs in soil-plant system as affected by dissolved organic matter (DOM). Thus DOM effect on NPs behavior is critical to assessing the environmental fate and risks related to NP exposure. Carbon-based nanomaterials embedded with metal NPs demonstrate a great potential to serve as catalyst and disinfectors. Hence, synthesis of novel carbon-based nanocomposites and testing them in the environmentally relevant conditions (particularly in the DOM presence) is important for their implementation in water purification. Sorption of DOM on Ag-Ag₂S NPs, CeO₂ NPs and synthesized Ag-Fe₃O₄-carbon nanotubebifunctional composite has been studied. High DOM concentration (50mg/L) decreased the adsorptive and catalytic efficiencies of all synthesized NPs. Recyclable Ag-Fe₃O₄-carbon nanotube composite exhibited excellent catalytic and anti-bacterial action, providing complete reduction of common pollutants and inactivating gram-negative and gram-positive bacteria at environmentally relevant DOM concentrations (5-10 mg/L). Our composite material may be suitable for water purification ranging from natural to the industrial waste effluents. We also examined the role of maize (Zeamays L.)-derived root exudates (a form of DOM) and their components on the aggregation and dissolution of CuONPs in the rhizosphere. Root exudates (RE) significantly inhibited the aggregation of CuONPs regardless of ionic strength and electrolyte type. With RE, the critical coagulation concentration of CuONPs in NaCl shifted from 30 to 125 mM and the value in CaCl₂ shifted from 4 to 20 mM. This inhibition was correlated with molecular weight (MW) of RE fractions. Higher MW fraction (> 10 kDa) reduced the aggregation most. RE also significantly promoted the dissolution of CuONPs and lower MW fraction (< 3 kDa) RE mainly contributed to this process. Also, Cu accumulation in plant root tissues was significantly enhanced by RE. This study provides useful insights into the interactions between RE and CuONPs, which is of significance for the safe use of CuONPs-based antimicrobial products in agricultural production. Wheat root exudates (RE) had high reducing ability to convert Ag+ to nAg under light exposure. Photo-induced reduction of Ag+ to nAg in pristine RE was mainly attributed to the 0-3 kDa fraction. Quantification of the silver species change over time suggested that Cl⁻ played an important role in photoconversion of Ag+ to nAg through the formation and redox cycling of photoreactiveAgCl. Potential electron donors for the photoreduction of Ag+ were identified to be reducing sugars and organic acids of low MW. Meanwhile, the stabilization of the formed particles was controlled by both low (0-3 kDa) and high (>3 kDa) MW molecules. This work provides new information for the formation mechanism of metal nanoparticles mediated by RE, which may further our understanding of the biogeochemical cycling and toxicity of heavy metal ions in agricultural and environmental systems. Copper sulfide nanoparticles (CuSNPs) at 1:1 and 1:4 ratios of Cu and S were synthesized, and their respective antifungal efficacy was evaluated against the pathogenic activity of Gibberellafujikuroi(Bakanae disease) in rice (Oryza sativa). In a 2-d in vitro study, CuS decreased G. fujikuroiColony- Forming Units (CFU) compared to controls. In a greenhouse study, treating with CuSNPs at 50 mg/L at the seed stage significantly decreased disease incidence on rice while the commercial Cu-based pesticide Kocide 3000 had no impact on disease. Foliar-applied CuONPs and CuS (1:1) NPs decreased disease incidence by 30.0 and 32.5%, respectively, which outperformed CuS (1:4) NPs (15%) and Kocide 3000 (12.5%). CuS (1:4) NPs also modulated the shoot salicylic acid (SA) and Jasmonic acid (JA) production to enhance the plant defense mechanisms against G. fujikuroiinfection. These results are useful for improving the delivery efficiency of agrichemicals via nano-enabled strategies while minimizing their environmental impact, and advance our understanding of the defense mechanisms triggered by the NPs presence in plants.
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