Дисертації з теми "Nanocatalysts for Hydrogenation reactions"
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He, Tianwei. "Computational discovery and design of nanocatalysts for high efficiency electrochemical reactions." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/203969/1/Tianwei_He_Thesis.pdf.
Повний текст джерелаEsmaeili, E., A. M. Rashidi, Y. Mortazavi, A. A. Khodadadi, and M. Rashidzadeh. "The Role of Pore Structure of SMFs-based Pd Nanocatalysts in Deactivation Behavioral Pattern Upon Acetylene Hydrogenation Reaction." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35216.
Повний текст джерелаWeiner, Jonathan. "Colloidal Cu/ZnO nanocatalysts for CO2 hydrogenation to methanol." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/57498.
Повний текст джерелаKonnerth, Hannelore [Verfasser]. "Towards Selective Hydrogenation using Metal Nanocatalysts in Ionic Liquids / Hannelore Konnerth." München : Verlag Dr. Hut, 2018. http://d-nb.info/1155057562/34.
Повний текст джерелаQuan, Xu. "Hydrogenation, Transfer Hydrogenation and Hydrogen Transfer Reactions Catalyzed by Iridium Complexes." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-119701.
Повний текст джерелаAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 5: Submitted. Paper 6: Manuscript.
Chen, H. Y. "Hydrogenation reactions catalysed by organometallic complexes." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1338140/.
Повний текст джерелаMacNair, Alistair James. "Iron-catalysed hydrogenation and hydroboration reactions." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28863.
Повний текст джерелаBryan, Aiden. "Electrochemical reactions." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318926.
Повний текст джерелаCao, X. M. "Insight into hydrogenation reactions in heterogeneous catalysis." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546020.
Повний текст джерелаShermer, Duncan J. "Sequential reactions involving catalytic transfer hydrogenation technology." Thesis, University of Bath, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432384.
Повний текст джерелаHall, Matthew Scott. "Gold catalysts for oxidation and hydrogenation reactions." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55942/.
Повний текст джерелаYap, Aaron J. "Hydrogenolysis, hydrogenation and nanoencapsulation in cascade reactions." Thesis, The University of Sydney, 2012. https://hdl.handle.net/2123/29153.
Повний текст джерелаChen, Dianjun [Verfasser]. "Novel strategies for asymmetric hydrogenation reactions / Dianjun Chen." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1018219838/34.
Повний текст джерелаWelther, Alice [Verfasser]. "Iron and Cobalt Catalyzed Hydrogenation Reactions / Alice Welther." München : Verlag Dr. Hut, 2013. http://d-nb.info/1047035820/34.
Повний текст джерелаCross, David J. "Asymmetric transfer hydrogenation reactions using Rh(III) catalysts." Thesis, University of Warwick, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403114.
Повний текст джерелаEllis, Ieuan. "Interstitial modification of palladium for partial hydrogenation reactions." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:7c8c294c-0583-4a61-98e5-4c32d76cbf89.
Повний текст джерелаMcLean, William Neil. "Metal catalysed reactions in organic chemistry." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257123.
Повний текст джерелаChan, Chun Wong Aaron. "Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:866296af-5296-4d2e-8e52-6499dacaef0f.
Повний текст джерелаMc, Geehin Peter Kevin Mark. "Hydrogenation, hydrogenolysis and reductive fission reactions of cis dihydrodiols." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252284.
Повний текст джерелаFu, Qi Jia. "A novel class of hydride catalysts for hydrogenation reactions." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252202.
Повний текст джерелаKolpin, Amy Louise. "A fundamental perspective on the effects of sulfur modification for transition metal nanocatalysts." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:41d587f5-9704-4a3a-bb34-71bd0e91862b.
Повний текст джерелаSchmidt, Andrea. "A pore flow through membrane reactor for selective hydrogenation reactions." [S.l.] : [s.n.], 2007. http://opus.kobv.de/tuberlin/volltexte/2007/1609.
Повний текст джерелаWei, Duo. "Iron, manganese and rhenium-catalyzed (de)hydrogenation and hydroelementation reactions." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S105.
Повний текст джерелаThis research work is aimed at developing advanced eco-friendly methodologies in the area of iron, manganese and rhenium-catalyzed (de)hydrogenation and hydroelementation reactions. Initially, we reported the first examples of highly selective catalytic direct C-H borylation of styrene derivatives and terminal alkynes with pinacolborane using Fe(PMe3)4 and Fe(OTf)2/DABCO as catalyst systems, respectively. Afterwards, N-heterocyclic carbene (NHC) based iron complexes Fe(CO)4(IMes) and [CpFe(CO)2(IMes)][I] were efficiently employed in the catalytic reductive amination reactions with hydrosilanes to access a large variety of cyclic amines (pyrrolidines, piperidines and azepanes). Interestingly, with the commercially available Mn2(CO)10 or Re2(CO)10 as catalyst and Et3SiH as an inexpensive hydrosilane source, carboxylic esters, acids and amides can be chemospecifically reduced to the corresponding acetals, alcohols and amines. Besides hydrosilylation, we also explored the application of a series of well-defined manganese pre-catalysts featuring readily available bidendate pyridinyl-phosphine and 2-picolylamine ligands in hydrogenation reactions of aldehydes, ketones and aldimines. In line with our interest in developing group 7 metals based catalysts, we have also demonstrated that a series of amino-bisphosphino ligands coordinated rhenium catalysts can efficiently promote the hydrogenation of carbonyl derivatives, the mono N-methylation of anilines with methanol and the dehydrogenative synthesis of substituted quinolines. Lastly we also developed the Mn-catalysed ligand- and additive-free aerobic oxidation of amines to prepare aldimines, N-heteroaromatics and benzoimidazole derivatives
Zhou, Xiwen. "Study of shape effect of Pd promoted Ga2O3 nanocatalysts for methanol synthesis and utilization." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:ed45a832-d0d5-4f1d-8c14-aa54df10e8cb.
Повний текст джерелаGeorgiades, G. C. "A study of cyclohexene reactions on supported characterised metal catalysts." Thesis, Brunel University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233346.
Повний текст джерелаHudson, Reuben. "Simple magnetic nanoparticles as catalysts for hydrogenation, condensation and coupling reactions." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121450.
Повний текст джерелаLes procédés chimiques impliquent souvent des catalyseurs de l'un des deux types suivants. Les catalyseurs hétérogènes (matériaux) constituent un système simple, qui peut généralement être aisément retiré du mélange réactionnel après usage. D'autre part, les catalyseurs homogènes (espèces solubles) sont souvent beaucoup plus difficiles à séparer ; en revanche, ils offrent en general une excellente performance catalytique étant donnée leur répartition homogène dans le milieu réactionnel. De plus, ces derniers peuvent être facilement modifiés par l'usage de divers ligands pour ainsi améliorer leur performance. L'utilisation croissante de nanoparticules en catalyse offre une alternative entre la catalyse homogène et hétérogène. De façon générale, plus leur taille est petite, plus les particules possèdent des propriétés catalytiques similaires à celles des systèmes homogènes. Malheureusement, la réduction de leur taille rend d'autant plus difficile leur séparation, comme dans le cas des systèmes homogènes. Pour résourdre ce problème de séparation, le domaine de la catalyse à base de nanoparticules magnétiques a vu le jour. Grâce à l'utilisation d'un aimant externe, les catalyseurs de nanoparticules magnétiques peuvent être récupérés et réutilisés facilement. Dans la plupart des exemples de catalyse faisant usage de nanoparticules magnétiques, les particules sont uniquement utilisées comme ancre pour la récupération magnétique, et non comme catalyseurs. Les stratégies complexes de ce type comprennent l'enrobage des nanoparticules avec un polymère ou bien avec de la silice, auquel un ligand de coordination peut être ancré. Par un tel système, on peut envisager l'ancrage de presque n'importe quel métal pseudo-homogène, ce qui permet un large éventail catalytique. L'objectif de ce travail est plutôt axé sur l'utilisation de nanoparticules magnétiques simples où les particules agissent non seulement comme moyen de récupération magnétique, mais également en tant que catalyseurs. Cette thèse porte sur trois types généraux de catalyseurs simples de nanoparticules magnétiques. Tout d'abord, il est démontré que des nanoparticules de fer réduit, dotés d'une coquille d'oxyde de fer, peuvent catalyser efficacement l'hydrogénation d'hydrocarbures insaturés. Cette réaction peut également être adaptée à un système "in flow", en préparant les nanoparticules en présence de polymères amphiphiles. Deuxièmement, considérant le potentiel catalytique limité du fer, la portée de ces réactions peut être étendue par la décoration de ces mêmes nanoparticules de fer / oxyde de fer à l'aide d'un second métal possédant un potentiel catalytique plus élevé. Des nanoparticules décorées de cuivre et de ruthénium ont été synthétisées et utilisées pour effectuer des réactions de couplage azoture-alcyne (click) et d'hydrogénation de transfert, respectivement. Troisièmement, il est démontré que d'autres métaux peuvent également directement être incorporés dans un réseau de nanoparticules magnétiques. Par exemple, des nanoparticules de CuFe2O4 peuvent être utilisées pour catalyser des réactions de condensation de Biginilli ainsi que des réactions de couplage inter-déshydrogénation. Par l'utilisation de ces trois types généraux de particules nues, nous avons élargi la portée des réactions catalysées par des nanoparticules magnétiques simples.
Cheng, Xiaohui. "Transition metal catalysed homogeneous hydroamination, allylic substitution and transfer hydrogenation reactions." Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410013.
Повний текст джерелаVono, Lucas Lucchiari Ribeiro. "Design of nanocatalysts supported on magnetic nanocomposites containing silica, ceria and titania." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-17082016-082602/.
Повний текст джерелаA separação magnética tem recebido muita atenção como uma tecnologia robusta, altamente eficiente e rápida para recuperar catalisadores sólidos após uso em reações em fase líquida. Muitos estudos têm focado nas metodologias para a imobilização de espécies cataliticamente ativas, mas o desenvolvimento de suportes magnéticos tem se limitado a nanopartículas magnéticas revestidas com sílica, polímeros ou carbono. O desenvolvimento de nanocompósitos magnéticos com a incorporação de outros óxidos é muito desejável para ampliar a aplicação dessa tecnologia de separação em catálise. Nesse contexto, estudos da estabilidade térmica de magnetita revestida com sílica (Fe3O4@SiO2) foram realizados para avaliar a possibilidade de calcina-la sem perder as propriedades magnéticas do suporte. Uma etapa de calcinação é necessária para a deposição de diferentes óxidos na superfície da sílica, tais como céria e titânia. O Fe3O4@SiO2 calcinado preservou a morfologia \"core-shell\" e as propriedades magnéticas, porém apresentou um aumentou de seis vezes na área superficial. Novos suportes magnéticos foram desenvolvidos pela deposição de céria e titânia sobre magnetita previamente revestida com sílica. Nanocatalisadores magneticamente recuperáveis de Rh, Pd e Ru foram preparados. Os catalisadores foram utilizados na hidrogenação de ciclo-hexano, benzeno ou fenol e o principal objetivo dessa tese foi o estudo da influência de cada suporte na atividade catalítica. Os catalisadores foram preparados de duas formas diferentes: impregnação-redução e imobilização de nanopartículas (NPs) metálicas pré-formadas. As NPs coloidais foram preparadas pela redução de sais metálicos e, também, pela decomposição de complexos organometálicos. Catalisadores de ródio preparados pela impregnação de cloreto de ródio(III) e redução com H2 mostraram alguns problemas de reprodutibilidade, que foram superados utilizando NaBH4 ou hidrazina como agentes redutores. A preparação de catalisadores pela imobilização de NPs coloidais é uma alternativa interessante para obter catalisadores reprodutíveis e muito ativos. Nanopartículas de Pd, Rh e Ru foram preparadas a partir de organometálicos e imobilizadas em Fe3O4@SiO2 calcinada, Fe3O4@SiO2CeO2 e Fe3O4@SiO2TiO2. A eliminação do agente estabilizante torna os catalisadores mais ativos durante os reusos. O catalisador de Rh sobre o suporte de céria foi o catalisador mais ativo na hidrogenação de ciclohexeno (TOF 125000 h-1). O catalisador de Pd foi o catalisador mais seletivo para a hidrogenação de fenol em ciclo-hexanona, independente do suporte usado. A formação de ciclo-hexanol é favorecida pelo suporte de titânia e a hidrodesoxigenação para produzir ciclo-hexano ocorreu principalmente no suporte de sílica.
Hanover, Karl Frederic. "The hydrogenation of glucose with Raney-nickel : an examination of the side reactions /." Thesis, Connect to this title online; UW restricted, 1987. http://hdl.handle.net/1773/5514.
Повний текст джерелаVaitsis, Evangelos. "Hydrogenation reactions under slug flow operation in the presence of catalyst rods." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/7993.
Повний текст джерелаLopez, Martinez Marco Antonio. "Studies of tartaric acid modified nickel supported catalysts for enantioselective hydrogenation reactions." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1491/.
Повний текст джерелаKotze, Hendrik de Vries. "Immobilized Ru(II) catalysts for transfer hydrogenation and oxidative alkene cleavage reactions." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96593.
Повний текст джерелаENGLISH ABSTRACT: The synthesis of a range of siloxane functionalized Ru(arene)Cl(N,N) complexes allowing for the synthesis of novel MCM-41 and SBA-15 immobilized ruthenium(II) catalysts, is described in this thesis. Two distinctly different approaches were envisaged to achieve successful heterogenization of these siloxane functionalized complexes. Condensation of the siloxane functionalized complexes, C2.4-C2.6 (siloxane tether attached to imine nitrogen) and C3.5-C3.7 (siloxane tether via the arene ring), with the surface silanols of the synthesized silica support materials MCM-41 and SBA-15, afforded immobilized catalysts IC4.1-IC4.6 (siloxane tether attached to imine nitrogen) and IC4.7-IC4.12 (siloxane tether via the arene ring). Model and siloxane functionalized complexes C2.1-C2.6 were prepared by the reaction of diimine Schiff base ligands L2.1-L2.6 with the [Ru(p-cymene)2Cl2]2 dimer. A second, novel, approach involved the introduction of the siloxane tether on the arene ligand of the complex. Cationic arene functionalized Ru(arene)Cl(N,N) complexes, C3.1-C3.4, were prepared with varying N,N ligands including bipyridine and a range of diimine ligands, with either propyl or diisopropyl(phenyl) substituents at the imine nitrogen (greater steric bulk around the metal center). The reaction of these propanol functionalized complexes with 3-(triethoxysilyl)propyl isocyanate, afforded urethane linked siloxane functionalized complexes C3.5-C3.8, where the siloxane tether is attached to the arene ring of the complex. The complexes were fully characterized by FT-IR spectroscopy, NMR (1H and 13C) spectroscopy, ESI-MS analysis and microanalysis. Suitable crystals for the alcohol functionalized complex C3.1 were obtained and the resultant orange crystals were analyzed by single crystal XRD. The heterogenized catalysts, IC4.1-IC4.12, were characterized by smallangle powder X-ray diffraction, scanning and transmission electron microscopy (SEM and TEM), thermal gravimetric analysis (TGA), inductively coupled plasma optical emission spectroscopy (ICP-OES) and nitrogen adsorption/desorption (BET) surface analysis to name but a few. ICP-OES allowed for direct comparison of the model and immobilized systems during catalysis ensuring that the ruthenium loadings were kept constant. The application of the model complexes C2.1-C2.3 and C3.1-C3.3, as well as their immobilized counterparts, IC4.1-IC4.12, as catalyst precursors in the oxidative cleavage of alkenes (1-octene and styrene), were investigated. The proposed active species for the cleavage reactions was confirmed to be RuO4 (UV-Vis spectroscopy). In general it was observed that at lower conversions, aldehyde was formed as the major product. Increased reaction times resulted in the conversion of the formed aldehyde to the corresponding carboxylic acid. For the oxidative cleavage of 1-octene using the systems with the siloxane tether attached to the imine nitrogen, the immobilized systems outperformed the model systems in all regards. Higher conversions and selectivities of 1-octene towards heptaldehyde were obtained when using immobilized catalysts IC4.1-IC4.6, as compared to their non-immobilized model counterparts (C2.1-C2.3) at similar times. It was found that the immobilized catalysts could be used at ruthenium loadings as low as 0.05 mol %, compared to the model systems where 0.5 mol % ruthenium was required to give favorable results. Complete conversion of 1-octene could be achieved at almost half the time needed when using the model systems as catalyst precursors. The activity of the model systems seems to increase with the increase in steric bulk around the metal center. These model and immobilized systems were also found to cleave styrene affording benzaldehyde in almost quantitative yield in some case (shorter reaction times). The systems, with the siloxane tether via the arene ring, were found to be less active for the cleavage of 1-octene when compared to the above mentioned systems (siloxane tether attached to the imine nitrogen). The immobilized systems IC4.7-IC4.12 performed well compared to their model counterparts, but could not achieve the same conversions at the shorter reaction times as were the case for IC4.1-IC4.6. This lower activity was ascribed to the decreased stability of these systems in solution compared to the above mentioned systems with the tether attached to the imine nitrogen. This was confirmed by monitoring the conversion of the complex (catalyst precursor) to the active species in the absence of substrate (monitored by UV-Vis spectroscopy). It was observed that model complex C3.1 could not be detected in solution after 1 hour, compared to complex C2.2 which was detected in solution even after 24 hours. Experiments were carried out where MCM-41 was added to a solution of model complex C2.2 under typical cleavage reaction conditions. A dramatic increase in the conversion was achieved when compared to a reaction in the absence of MCM-41. An investigation into the effect of the support material on the formation of the expected active species was carried out using UV-Vis spectroscopy. The presence of the active species, RuO4, could be observed at shorter reaction times in the presence of MCM-41. This suggested that the silica support facilitates the formation of the active species from the complex during the reaction, therefore resulting in an increased activity. It was also observed that RuO4 is present in solution in reactions where the immobilized catalyst systems are used after very short reaction times, compared to the prolonged times required for this to occur as is the case for the model systems. Model and immobilized catalysts, C2.1-C2.3 and IC4.1-IC4.6, were also applied as catalysts for the transfer hydrogenation of various ketones. The immobilized systems could be recovered and reused for three consecutive runs before the catalysts became inactive (transfer hydrogenation of acetophenone). Moderate to good conversion were obtained using the immobilized systems, but were found to be less active their model counterparts C2.1-C2.3.
AFRIKAANSE OPSOMMING: Die sintese van `n reeks siloksaan gefunksioneerde Ru(areen)Cl(N,N) komplekse, wat die sintese van nuwe MCM-41 en SBA-15 geimmobiliseerede rutenium(II) katalisatore toelaat, word in hierdie tesis beskryf. Twee ooglopend verskillende metodes is voorgestel om die suksesvolle immobilisering van die siloksaan gefunksioneerde komplekse te bereik. Die kondensasie van die siloksaan gefunksioneerde komplekse, C2.4-C2.6 (siloksaan ketting geheg aan die imien stikstof) en C3.5-C3.7 (siloksaan ketting geheg aan die areen ligand), met die oppervlak silanol groepe van die silika materiale MCM-41 en SBA-15, laat die sintese van geimmobiliseerde katalisatore IC4.1-IC4.6 (siloksaan ketting geheg aan die imien stikstof) en IC4.7-IC4.12 (siloksaan ketting geheg aan die areen ligand) toe. Model en siloksaan gefunksioneerde komplekse C2.6-C2.6 is berei deur die reaksie tussen Schiff basis ligande, L2.1-L2.6, en die [Ru(p-simeen)2Cl2]2 dimeer. `n Tweede, nuwe benadering wat die sintese van komplekse met die siloksaan ketting geheg aan die areen ligand behels, is ook gevolg. Kationiese areen gefunksioneerde Ru(areen)Cl(N,N) komplekse, C3.1-C3.4, is berei deur die N,N ligande rondom die metaal sentrum te wissel vanaf bipiridien tot `n reeks diimien ligande met propiel of diisopropielfeniel substituente by die imien stikstof. Hierdie propanol gefunksioneerde komplekse is met 3-(triëtoksiesiliel)propiel-isosianaat gereageer om sodoende die uretaan gekoppelde siloksaan gefunksioneerde komplekse C3.5-C3.8 op te lewer. Al die komplekse is ten volle gekaraktariseer deur van FT-IR spektroskopie, KMR (1H and 13C) spektroskopie, ESI-MS analise en mikroanalise gebruik te maak. In die geval van model kompleks C3.1, is `n kristalstruktuurbepaling ook uitgevoer. Die heterogene katalisatore, IC4.1- IC4.12, is gekaraktariseer deur poeier X-straaldiffraksie, skandeer- en transmissieelektronmikroskopie, termogravimetriese analise (TGA), induktief gekoppelde plasma optiese emissie spektroskopie (IKP-OES) en BET oppervlak analises, om net `n paar te noem. IKP-OES het ons toegelaat om `n direkte vergelyking te tref tussen die model en geimmobiliseerde sisteme tydens die katalise reaksies. Model komplekse C2.1-C2.3 en C3.1-C3.3, sowel as hul geimmobiliseerde eweknieë IC4.1- IC4.12, is vir die oksidatiewe splyting van alkene (1-okteen en stireen) getoets. Die voorgestelde aktiewe spesie wat tydens hierdie reaksie gevorm word, RuO4, is bevestig deur van UV-Vis spektroskopie gebruik te maak. Oor die algemeen is dit gevind dat aldehied oorheersend gevorm word by laer omsetting. Wanneer die reaksietyd verleng is, is daar gevind dat die aldehied na die ooreenstemmende karboksielsuur omgeskakel is. Wanneer die geimmobiliseerde katalisatore gebruik is tydens die oksidatiewe splitsing van 1-okteen, het die sisteme, met die ketting geheg aan die imien stikstof, deurgangs beter as die model sisteme gevaar. Hoër omskakelings van 1-okteen en hoë selektiwiteite vir heptaldehied is behaal wanneer die geimobiliseerded katalisatore IC4.1-IC4.6 met die nie-geimmobiliseerde model sisteme (C2.1- C2.3) vergelyk is by dieselfde reaksietye. Die geimobiliseerde sisteme kon by rutenium beladings van so laag as 0.05 mol % gebruik word. Dit is in teenstelling met die model sisteme waar 0.5 mol % rutenium nodig was om die reaksie suksesvol te laat plaasvind. Die totale omskakeling van 1-okteen is bereik in die helfte van die tyd wat nodig was wanneer die model sisteme gebruik is. Dit is gevind dat die aktiwiteit van die model sisteme toeneem met `n toename in die steriese grootte van die ligand rondom die metaal. Beide die model en geimmobilseerde sisteme kon ook gebruik word vir die oksidatiewe splyting van stireen. Bensaldehied kon in kwantitiewe opbrengs gevorm word in sommige gevalle. `n Laer aktiwiteit vir die oksidatiewe splyting van 1-okteen is vir die sisteme waar die siloksaan ketting aan die areen ligand geheg is, waargeneem. Hoewel die geimmobiliseerde sisteme IC4.7-IC4.12 beter as hul model eweknieë gevaar het, kon die aktiwiteite wat met IC4.1-IC4.6 bereik is nie geewenaar word nie. Hierdie laer aktiwiteit is toegeskryf aan die verlaagde stabiliteit van dié sisteme in oplossing in vergelyking met IC4.1-IC4.6 (ketting geheg aan die imine stikstof). Die stabiliteit van beide sisteme is getoets deur die omskakeling van die model komplekse (C2.2 en C3.1; katalise voorgangers) na die aktiewe spesie te monitor (UV-Vis spektroskopie). Na 1 uur kon die model kompleks C3.1 nie meer in die oplossing waargeneem word nie. In teenstelling kon model kompleks C2.2 nog selfs na 24 uur in die oplossing bespeur word. Om die rol van die silika materiale tydens die reaksie te ondersoek, is `n eksperiment uitgevoer waar MCM-41 by `n oplossing van kompleks C2.2 gevoeg is. `n Toename in die omskakeling van 1-okteen is waargeneem in vergelyking met `n reaksie waar geen silika teenwoordig was nie. UV-Vis spektroskopie is gebruik om die invloed van die silika op die vorming van die aktiewe spesie te ondersoek. In eksperimente waar MCM-41 teenwoordig was, kon die aktiewe spesie, RuO4, by baie korter reaksietye waargeneem word. Dit wil blyk of die silika materiaal die vorming van die aktiewe spesie vanaf die kompleks aanhelp en sodoende `n toename in die spoed van die reaksie bewerkstellig. RuO4 kon ook by baie korter reaksietye waargeneem word wanneer die geimmobiliseerde sisteme gebruik is. Beide model en geimmobiliseerde sisteme, C2.1-C2.3 en IC4.1-IC4.6, is getoets vir die oordrag hidrogenering van verskilende ketone. Dit was moontlik om die geimmobiliseerde sisteme drie keer te herwin en vir daaropvolgende reaksies te gebruik. Vir die geimmobiliseerde sisteme kon egter slegs gemiddelde omskakelings verkryg word en het swakker gevaar as hul model ekwivalente sisteme, C2.1-C2.3.
Goda, Amit. "Correlating electronic and catalytic properties of bimetallic surfaces for model hydrogenation reactions." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 184 p, 2009. http://proquest.umi.com/pqdweb?did=1654493511&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Повний текст джерелаSopaci, Saziye Betul. "Microorganism Mediated Stereoselective Bio-oxidation And Bio-hydrogenation Reactions And Thiamine Pyrophosphate Dependent Enzyme Catalyzed Enantioselective Acyloin Reactions." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610516/index.pdf.
Повний текст джерела90% yield) confirming the suggested mechanism of oxidation-reduction sequence of hydrobenzoin. Wieland-Miescher ketone (3,4,8,8a-tetrahydro-8a-methylnaphthalene-1,6(2H,7H)-dione) is an important starting material for bioactive compounds like steroids and terpenoids. Many synthetic approaches include enantioselective reduction of this compound. In this study Aspergillus niger (MAM 200909) mediated reduction of Wieland-Miescher ketone was achieved with a high yield (80%), de (79%) and ee (94%) value and these results were found much more superior than previously reported studies. Carboligating enzymes benzaldehyde lyase (BAL) (EC 4.1.2.38) and benzoiyl formate decarboxilase (BFD) (E.C. 4.1.1.7) are used for biocatalytic acyloin synthesis. These enzymes are immobilized to surface modified superparamagnetic silica coated nanoparticles by using metal ion affinity technique. With this system recombinant histidine tagged BAL and BFD purified and immobilized to magnetic particles by one-pot purification-immobilization procedure. SDS page analysis showed that our surface modified magnetic particles were eligible for specific binding of histidine tagged proteins. Conventional BAL and BFD catalyzed benzoin condenzation reactions and some representative acyloin reactions were performed with this system with a high enantioselectivity (99-92%) and yield. Results obtained with magnetic particle-enzyme system were also found comparable with that of free enzyme catalyzed reactions.
Nagendiran, Anuja. "Catalytic reactions with palladium supported on mesocellular foam : Applications in hydrogenation, isomerization, and C-C bond forming reactions." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-122061.
Повний текст джерелаAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Submitted. Paper 5: Submitted.
Liu, Hang. "In situ investigations of chemical reactions on ZnO-Pt model nanocatalysts for environmentally friendly energy generation sources." Electronic Thesis or Diss., Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2019SORUS201.pdf.
Повний текст джерелаThe ZnO/Pt(111) catalyst has been shown to exhibit remarkable catalytic performances in the low temperature CO oxidation. The identification of the active sites in CO oxidation is important for a mechanistic understanding of the structure-reactivity relationship. We first established a recipe to fabricate ZnO thin films on Pt(111) using e-beam evaporation, characterized by STM and LEED. The film grows in layer-by-layer mode, starting from a graphene-like monolayer tothe ZnO(0001)-Zn terminated surface. The role of the ZnO/Pt boundaries was revealed by STM ex situ after exposure to the O2: CO mixture. To shedlight on the role of the boundaries, a systematic comparative study of the ZnO/Pt(111) catalyst with the Pt(111) surface was under taken. The mass spectroscopy and gas phase NAP-XPS analysis were relevant, to determine the regimes where mass transfer limitation starts to occur, allowing a discussion on the relation between steady-state molar fractions of reactants/product and surface reactivity, and to calibrate the surface density of the adsorbates.Solid phase XPS spectra gave us access to the dynamics of the ZnO monolayer film covering only partially the Pt(111) surface. The role of ZnO-bound hydroxyls was highlighted by the observation of the chemical signature of the CO+OH associative reaction products. The carboxyl formed at the low temperature can be the intermediate species that leads to the evolution of CO2, the OHs at the Pt/ZnO boundary being the co-catalyst, which explains the synergistic effect of ZnO and Pt
Hwang, Sang Youp. "Synthesis of Platinum Based Nanocatalysts with Controlled Particle Parameters and Study for Their Properties in Oxidation Reactions." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1478705075812659.
Повний текст джерелаAzhari, C. H. "Characterisation and activity of polymer supported platinum and gold in catalytic hydrogenation reactions." Thesis, Brunel University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.351570.
Повний текст джерелаSeashore-Ludlow, Brinton. "New Methods for the Synthesis of Vicinal Stereocenters : Palladium-Catalyzed Domino Reactions and Asymmetric Transfer Hydrogenation." Doctoral thesis, KTH, Organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-95327.
Повний текст джерелаQC 20120605
Amar, Yehia. "Accelerating process development of complex chemical reactions." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288220.
Повний текст джерелаFurst, Marc R. L. "Polymer precursors from catalytic reactions of natural oils." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3684.
Повний текст джерелаLyu, Ye. "Cobalt-catalyzed Hydroelementation Reactions." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS611.
Повний текст джерелаThis thesis was focused on well-defined low-valent cobalt complexes HCo(PMe3)4/HCoN2(PPh3)3, the bench stable family Cp*Co(III) of complexes and their applications in R–H activation (R = B, C, Si). First, we successfully used the HCo(PMe3)4 complex to catalyze regio- and stereo-selective hydroboration and diboration of alkynes. In addition, we exploited the HCo(PMe3)4 complex to catalyze silaboration of alkyne. Then, we demonstrated that the HCo(PMe3)4 complex and HCoN2(PPh3)3 complex were useful in the stereo-divergent hydrogenation of alkynes. Finally, we explored the application of the bench- stable Cp*Co(III) together with chiral additives in asymmetrical C–H bond functionalization. In addition, we conducted the elementary exploitation in synthesis of chiral Cp*Co(III) complexes
Li, Yingze. "Development of New Cobalt Pincer Complexes for Catalytic Reduction Reactions." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1554215914263187.
Повний текст джерелаAmpurdanés, Vilanova Jordi. "Novel Catalytic Materials and Strategies for Hydrogen Production and Hydrogenation Reactions based on PEM Electrolysis." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/319946.
Повний текст джерелаLa producción de hidrógeno, a gran escala, a partir de agua se ha convertido en un reto desde ya hace unos cuantos años. Así, una vía ecológica y eficiente para la generación de hidrógeno tiene que establecerse. Entre todas las posibilidades, electrólisis mediante la tecnología de membranas de intercambio de protones (PEM) es la técnica más prometedora para conseguir dicho propósito. Además, dicha aproximación también puede ser considerada para llevar a cabo otras reacciones electroquímicas con propósitos totalmente distintos a la producción de hidrógeno, como por ejemplo, la reducción de contaminantes de origen químico. A la luz de estos antecedentes, reactores electroquímicos multifuncionales basados en membranas de intercambio protónicas, integrados en un sistema en flujo, para (1) producción de hidrógeno y (2) reducción de nitratos (contaminante estudiado) a nitrógeno, fueron diseñados, construidos y evaluados, satisfactoriamente. Catalizadores heterogéneos basados en metales fueron utilizados como materiales de electrodo para realizar las reacciones electroquímicas deseadas. MoS2, así como, Co3O4 fueron descubiertos como materiales prometedores para la producción de hidrógeno en sistemas de electrólisis PEM, debido a su rendimiento, precio y abundancia en la corteza terrestre. Empleando la misma estrategia, catalizadores soportados en SnO2 fueron utilizados para la reducción en continuo de nitratos, en fase acuosa, bajo condiciones electroquímicas. Esta aproximación fue llamada reducción de nitratos asistida mediante electrolisis. Catalizador de SnO2 modificado con PdCu destacó como el material de electrodo con mejor rendimiento en términos de conversión y selectividad. Mediante la modificación de los parámetros de trabajo, así como, la configuración del reactor, la versatilidad y flexibilidad de esta estrategia fueron evaluadas para poder ajustar la formación de productos durante la reacción.
Large-scale hydrogen production from water has become a challenge since several years ago. Thus, a clean and efficient way for hydrogen generation has to be stablished; among all possibilities, electrolysis by means of proton exchange membrane (PEM) technology is the most promising technique to achieve such goal. Furthermore, this approach can be also considered as potential strategy to perform electrochemical reactions for other purposes rather than only hydrogen production, like chemical pollutants reduction. In the light of this backgrounds, a multipurpose proton exchange membrane (PEM) electrocatalytic reactors, integrated in a flow system, for (1) hydrogen production and (2) nitrate reduction (target pollutant) towards nitrogen, were successfully designed, constructed and lately evaluated. Metal-based heterogeneous catalysts were employed as electrode material to carry out desired electrochemical reactions. MoS2 as well as Co3O4 were found as promising materials for hydrogen production in PEM electrolysis system due to its performance, price and abundance on Earth’s crust. Using same strategy, SnO2 supported catalysts were employed for continuous aqueous phase nitrate reduction under electrochemical conditions. This approach was called electrolysis-assisted nitrate reduction. PdCu dopped SnO2 catalyst stood up as the best performing electrode material in terms of conversion and selectivity. By modifying working parameters as well as reactor configuration, versatility and flexibility of this strategy were evaluated in order to fine tune products formation during reaction.
Stanford, John Paul. "Development and characterization of noble metal integrated polymeric membrane reactors for three-phase hydrogenation reactions." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32512.
Повний текст джерелаDepartment of Chemical Engineering
Mary E. Rezac
Catalytic membrane reactors are a class of reactors that utilize a membrane to selectively deliver reactants to catalysts integrated in the membrane. The focus of this research has been on developing and characterizing polymeric catalytic membranes for three-phase hydrogenation reactions, where the membrane functions as a gas/liquid phase contactor allowing selective delivery of hydrogen through the membrane to reach catalytic sites located on the liquid side of the membrane. The benefit of conducting three-phase reactions in this manner is that delivering hydrogen through the membrane to reach catalytic sites avoids the necessity of hydrogen dissolution and diffusion in the liquid phase, which are both inherently low and often described as causing mass-transfer and reaction rate limitations for the reactive system. This work examines two types of membrane reactor systems, porous polytetrafluoroethylene and asymmetric Matrimid membranes, respectively, for the ruthenium catalyzed aqueous phase hydrogenation of levulinic acid. The highly hydrophobic PTFE material provides an almost impermeable barrier to the liquid phase while allowing hydrogen gas to freely transport through the pores to reach catalytic sites located at the liquid/membrane interface. Catalytic rates as a function of hydrogen pressure over the range 0.07 to 5.6 bar are presented and shown to be higher than those of a packed bed reactor under similar reaction conditions. An increasing catalytic benefit was obtained operating at temperatures up to 90 °C, which is attributed to increased hydrogen permeability and avoidance of the decreasing solubility of hydrogen in water with increasing temperature. The membrane reactor was shown to be stable with no decrease in catalytic activity over 200 hours of operation. The Matrimid membrane reactor work demonstrates the feasibility of applying an integrally-skinned asymmetric membrane for an aqueous phase hydrogenation reaction and focuses on the impact that membrane hydrogen permeance and catalyst loading have on catalytic activity. The non-porous nature of the separating layer in the Matrimid membrane allowed successful operation up to 150 °C. The overall catalytic rates were approximately an order of magnitude lower than those achieved in the PTFE membrane reactor system due primarily to significantly lower hydrogen permeances, nevertheless rates were still higher than control experiments. This work also focuses on characterizing Matrimid/solvent thermodynamic relationships for a variety of organic solvents, looking at sorption, diffusion, and polymer relaxation behavior in thin films ranging from 0.1 to 2.0 µm in thickness using quartz crystal microbalance techniques. Diffusion coefficients at infinite dilution for water and C1-C6 alcohols are given as a function of van der Waals molar volume and a clear dependency is shown ranging from 2E-11 to 6.5E-13 cm²/s for water and hexanol, respectively, for 0.26 µm thick films. Diffusion coefficients for all studied vapor penetrants displayed a marked dependence on thickness spanning approximately two orders of magnitude for each respective vapor penetrant over the range 0.1 to 1.0 µm. Chemically cross-linking Matrimid is a method to mitigate some of the relatively high sorption and swelling behavior exhibited in the presence of sorbing species. An in-depth analysis on the vapor phase ethylenediamine cross-linking of Matrimid films and its impact on diffusion, sorption, and relaxation is also described.
Bonnafoux, Laurence. "Modular synthesis of new C1-biaryl ligands and application in catalyric hydrogenation and coupling reactions." Université Louis Pasteur (Strasbourg) (1971-2008), 2008. http://www.theses.fr/2008STR13237.
Повний текст джерелаTransition metal enantioselective catalysis is certainly among the most challenging and widely investigated area in modern organometallic chemistry. Chiral compounds qualifying as ligands for asymmetric catalysis continue to be designed and synthesized at a frenetic pace and competitors keep on emerging. In the field of atropisomeric biaryl diphosphine ligands, BINAP and MeO-BIPHEP are one of the most efficient one. On the other hand, the literature only shows very few C1-symmetric examples in this ligand class, none of them having a high structural or electronic diversity. In this context, we disclosed the access to the following C1-symmetric mono- and diphosphine ligands and we studied the influence of their steric and electronic properties. Most of them were obtained via aryne coupling, regioselective halogen/lithium exchange, phosphination sequence. Their electronic profile i. E. Their s-donor properties and their p-acidic character were determined according to the classical methods. Finally, we used them in catalytic hydrogenations of C-C and C-O double bonds and C-C Suzuki-Miyaura coupling reactions and we proved that whatever the reaction, at least one of our ligands was as efficient as the classical ones
ALIJANI, SHAHRAM. "EFFECT OF THE PREPARATION OF THE CATALYST AND PROTECTIVE AGENT IN LIQUID PHASE HYDROGENATION REACTIONS." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/816935.
Повний текст джерелаReynders, Frederik Jakobus Wilhelm. "Gas-limited hydrogenation of 1-octene in a packed bed reactor." Diss., University of Pretoria, 2011. http://hdl.handle.net/2263/26555.
Повний текст джерелаTrifonova, Anna. "Synthesis of Novel Chiral Bicyclic Ligands and their Application in Iridium-Catalyzed Reactions." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5783.
Повний текст джерелаVom, Stein Thorsten [Verfasser]. "Catalytic multistep hydrogenation and hydrogenolysis reactions for the utilization of renewable carbon resources / Thorsten Vom Stein." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1065848684/34.
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