Dissertations / Theses: 'Carbon monoxide Catalysts'

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Blank, Jan Hendrik. "Carbon monoxide hydrogenation using ruthenium catalysts." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3470.

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Kennedy, Sinead A. "Infrared studies of adsorption on model catalysts." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250661.

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Mirzaei, Ali Akbar. "Low temperature carbon monoxide oxidation using copper containing catalysts." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266493.

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Kureppadathu, Raman Sumesh. "Carbon monoxide/heterocycle copolymerisation : new catalysts and new biodegradable polymers." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066575.

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Certains polymères synthétiques biodégradables ont montré des propriétés physico-chimiques aussi intéressantes que celles des plastiques issus du pétrole. Cependant, leur coût élevé dû au prix des matières premières ainsi qu’au faible nombre de voies de synthèse efficaces empêchent leur rentabilité. Une des alternatives serait le développement de méthodes de production viables économiquement par l’utilisation de catalyseurs productifs et de voies de synthèses à économie d’atomes. Ce manuscrit rassemble les travaux effectués durant la thèse sur une série de catalyseurs organométalliques hautement actifs pour la synthèse du poly(lactide), de nouvelles stratégies catalytiques pour la production du poly(3-hydroxybutyrate) et la polymérisation à économie d’atomes d’α-aminoacide-N-carboxyanhydrides pour la production de poly(α-peptides)
Many synthetic biodegradable polymers show competitive physical properties compared to petrochemically derived plastics. However, due to the low availability and high cost of renewable feed stocks or lack of efficient synthetic routes, their industrial production and successful commercial execution lacks economical feasibility. One way to improve the current situation is the implementation of cost efficient methods either by using productive catalysts or by atom-efficient synthetic methods. Here we report the discovery of a series of highly active organometallic catalysts for the synthesis of poly(lactide), new catalytic methodologies for the production of poly(3-hydroxybutyrate), and an atom-efficient polymerization of α-aminoacid-N-carboxyanhydrides to poly(α-peptides)

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Chan, Sze Chi. "Novel photodeposited catalysts for carbon monoxide oxidation and preferential oxidation of carbon monoxide in the presence of hydrogen (PROX)." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 332 p, 2008. http://proquest.umi.com/pqdweb?did=1654493521&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Lloyd, Nicholas Charles. "Tin(IV) oxide based emission control catalysts." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338436.

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Ying, Fang. "Au/CeO₂ based catalysts for catalytic oxidation of volatile organic compounds and carbon monoxide." HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1185.

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Ho, Ka Yee. "Nanostructured environmental catalysts for carbon monoxide and volatile organic compounds removal /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202006%20HO.

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Kikukawa, Shingo. "Development of late transition metal catalysts for olefin polymerization." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325839.

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Yetisemiyen, Pelin. "Low Temperature Photocatalytic Oxidation Of Carbon Monoxide Over Palladium Doped Titania Catalysts." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612466/index.pdf.

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The room temperature photocatalytic oxidation of carbon monoxide in excess air was examined over silica/titania and 0.1%palladium/silica/titania catalysts under UV irradiation. The experiments were conducted in batch re-circulated reactor with the initial 1000 ppm carbon monoxide in air and 0.5 g catalyst charge and the conversion of carbon monoxide to carbon dioxide was followed by FT-IR spectro-photometer. The change in gas composition in dark and under 36 Watts of UV irradiation exposed to a catalyst area of 12.4 centimeter square indicated both adsorption of carbon monoxide and conversion of carbon monoxide to carbon dioxide over the catalyst samples. The effect of catalyst composition (silica/titania) ratio and the presence of palladium oxide were investigated. The catalyst samples were synthesized by sol-gel technique and all samples were hydrothermally treated before calcination in air. The catalyst samples were characterized by XRD and nitrogen adsorption techniques. XRD results indicated that titania is comprised of pure anatase phase and palladium oxide preferantially dispersed over titania. BET surface area of the samples were observed to increase with silica loading and the BJH results showed isotherms of Type V v with H2 hysteresis loops. The highest carbon monoxide adsorption rate constant was achieved with pure silica with the highest surface area. Photocatalytic activity measurements indicated that carbon monoxide in excess air can be successfully oxidized at room temperature over the titania photocatalyts. Higher physisorption was observed over higher silica containing samples and higher oxidation activity was observed with increasing titania/silica ratio. The optimum titania/silica ratio was determined by the titania content and surface area of catalyst. The activity tests were also indicated that the addition of palladium oxide phase synergistically increased the adsorption and oxidation activity of the catalysts.

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Jones, Christopher D. "Ambient temperature oxidation of carbon monoxide by copper-manganese oxide based catalysts." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56078/.

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The catalytic oxidation of carbon monoxide is an important reaction both commercially and scientifically. Copper-manganese oxides in the form of hopcalite have formed a cheap and accessible carbon monoxide abatement catalyst for the last 80 years. This thesis outlines the robust and reproducible preparation methods necessary for the formation of highly active species, with the heat treatment applied during the catalyst drying steps being identified as crucial for the formation of active species. The addition of metal cations (Co3+, Ni2+, Fe3+, Ag+) to the standard hopcalite formulation has given rise to many interesting properties including increased intrinsic activity, increased surface area and greater stability of catalytic activity with increased usage. The results of doping with a small quantity of cobalt produced materials that were amorphous to X-Ray Diffraction studies and with increased surface areas over the standard hopcalite. The dual positive effects of increased activity and prolonged catalyst stability were also brought about by the addition of cobalt (1-5% with respect to the quantity of copper present). The joint effect of precipitate ageing time and level of cobalt doping is also probed. The poisoning effect of water on the hopcalite and cobalt-doped hopcalite is reported, with the effect being identified as temporary and reversible in many cases. The mechanisms of oxidation and deactivation over hopcalite are probed using the Temporal Analysis of Products technique with the important relationship between lattice oxygen and catalytic activity being identified. The presence of cobalt is also shown to be important to the re-oxidation of a reduced hopcalite surface. Catalysts were produced that rivalled and often improved on the activity and stability of a presently available commercial catalyst.

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Qiu, Yongfu. "Preparation and characterization of nano-gold catalysts supported on ceria-based materials for carbon monoxide and benzene complete oxidation." HKBU Institutional Repository, 2005. http://repository.hkbu.edu.hk/etd_ra/626.

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Aldridge, James K. W. "Heterogeneous CuMn2O4, Pt, Pd and SnO2 catalysts for ambient temperature oxidation of carbon monoxide." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/33320/.

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Ambient temperature oxidation of carbon monoxide is a vital reaction for life support in enclosed atmospheres such as submarines and spacecraft. This reaction is usually achieved through the use of two classes of catalyst. Firstly, mixed copper and manganese oxides designated ‘Hopcalite’ or CuMn2O4. Secondly, high surface area noble metal catalysts deposited on durable metal oxide supports. Both of these classes of catalyst are investigated in this thesis, with the aim of producing novel, reproducible, robust and active ambient temperature carbon monoxide oxidation catalysts. In this thesis, CuMn2O4 is sequentially doped and/or impregnated with low weightings (1-10%) of the transition metals V and Ce, noble metals Pd and Pt and metalloid Si in an attempt to improve activity and moisture resistance. It was observed that doped V, Ce, Pd and Si are catalytic poisons toward CuMn2O4. This is likely due to their interference in the Cu ↔ Mn redox mechanism. XRD investigations infer doped Pd is a structural promoter toward CuMn2O4, increasing surface area and decreasing catalyst crystalinity. Impregnation of noble metals Pt and Pd onto CuMn2O4 surface causes deactivation of the noble metals, most likely due to the oxidation of Pt and Pd by Mn. No novel catalyst tested in this thesis displayed increased resistance to moisture deactivation. Noble metals Pt and Pd were impregnated upon 3 mm diameter Al2O3 spheres and tested for ambient temperature CO oxidation activity. The positive synergy between the two metals is measured, and the most efficient Pt:Pd ratio is discovered to be ~ 1:4. A novel, atom efficient method, for synthesising Pt/Pd/SnO2/Al2O3 catalysts using tin oxalate was conceived of and investigated. Compared to existing reference catalysts, oxalate derived catalysts preformed favourably and can be described as equivalently active.

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Gu, Bang. "Design of metal catalysts for carbon monoxide hydrogenation with high activity, selectivity and stability." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R020/document.

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La synthèse de Fischer-Tropsch (FT) est l’un des moyens les plus pratiques de convertir les ressources carbonées alternatives, telles que le charbon, la biomasse, le gaz naturel et le gaz de schiste, en carburants et en produits chimiques à haute valeur ajoutée via le gaz de synthèse. Les hydrocarbures issus de la synthèse FT suivent une distribution large Anderson-Schulz-Flory (ASF). C’est donc un grand défi d’améliorer la sélectivité en hydrocarbures spécifiques. En plus de la sélectivité, la stabilité insuffisante des catalyseurs restreint une large implémentation de la synthèse FT dans l’industrie.Les effets dus à la promotion des catalyseurs au fer supporté par des nanotubes de carbone au bismuth et au plomb sur la synthèse directe d’oléfines légères à partir de gaz de synthèse ont été étudiés dans le chapitre 3. Par rapport aux catalyseurs au fer non promus, une vitesse de réaction de Fischer-Tropsch deux fois plus importante et une sélectivité considérablement plus élevée ont été observées. Une migration remarquable des promoteurs lors de l’activation du catalyseur et une décoration des nanoparticules de carbure de fer par les promoteurs ont été mis en évidence.Dans le chapitre 4, en utilisant un large éventail de techniques ex situ et in situ, nous avons découvert, plusieurs effets synergiques majeurs issus du nanoconfinement du fer dans les nanotubes de carbone et de sa promotion au bismuth et au plomb sur la structure et les performances catalytiques. Le nanoconfinement du fer dans les nanotubes de carbone, associé à la promotion au Bi ou au Pb, permet d'obtenir un rendement en oléfines légères dix fois plus élevé. Le nanoconfinement conduit principalement à des meilleures dispersion et stabilité, tandis que l’activité intrinsèque du fer (TOF) reste inchangée. La promotion au Bi et au Pb entraîne une augmentation majeure du TOF dans les catalyseurs confinés et non confinés. Apres l’optimisation, la synthèse Fischer-Tropsch se produit sous pression atmosphérique avec une conversion élevée et une sélectivité accrue en oléfines légères sur les catalyseurs promus et confinés.Dans le chapitre 5, nous avons examiné l’effet de la taille des particules de fer dans les catalyseurs confinés sur la conversion du gaz de synthèse en oléfines Nous avons démontré d’un part, que le TOF augmente lors que la taille des nanoparticules de fer confinés promues ou non-promues augmente de 2.5 à 12 nm. D’autre part, la sélectivité en olefines légères dépend fortement de la promotion. Dans les catalyseurs non-promus, la taille des particules de fer encapsulées dans les nanotubes de carbone ne produit aucun effet notable sur la sélectivité en oléfines légères, tandis que dans les catalyseurs promus au Bi et au Pb, la sélectivité en oléfines légères était supérieure sur les petites nanoparticules de fer et diminuait avec l’augmentation de la taille de nanoparticules.Dans le chapitre 6, nous avons élaboré une nouvelle approche pour la synthèse d’oléfines alpha linéaires lors de la synthèse de FT à basse température sur les catalyseurs à base de Co. Nous avons constaté que la co-alimentation du syngas en acides carboxyliques induisait une modification de la sélectivité et son déplacement vers les oléfines alpha. La sélectivité en olefines alpha atteint 39 % en présence des acides.En fin, nous avons proposé une nouvelle stratégie pour améliorer considérablement la stabilité des catalyseurs Co et Ni pour l'hydrogénation du CO via leur promotion au bismuth. Les catalyseurs promus ont démontré une stabilité exceptionnelle lors de la réaction. Les expériences menées ont révélé l'auto-régénération continue du catalyseur au cours de la réaction via l’oxydation du carbone déposé par l'oxygène généré lors de la dissociation du CO à l'interface de nanoparticules métalliques et du promoteur de bismuth. La formation d’une couche de bismuth protégeait également les nanoparticules métalliques du frittage
Fischer-Tropsch (FT) synthesis is one of the most practicable routes to convert non-petroleum carbon resources, such as coal, biomass, natural gas and shale gas, via syngas into valuable fuels and chemicals. This reaction follows surface polymerization mechanism and the primary products follows the Ander-Schulz-Flory (ASF) distribution. It’s a big challenge to improve the target products selectivity. Apart from the selectivity, catalyst deactivation also restricts the wide application in FT synthesis. The effect of the promotion with bismuth and lead on direct synthesis of light olefins from syngas over carbon nanotube supported iron catalysts was investigated in Chapter 3. Compared to the un-promoted iron catalysts, a twice higher Fischer-Tropsch reaction rate and higher selectivity to light olefins were obtained. This promotion effect is more significant under atmospheric pressure with 2-4 times higher activity while the selectivity of light olefins reaches as high as ~60 %. Remarkable migration of promoters during the catalyst activation and decoration of the iron carbide nanoparticles were uncovered by characterization. Moreover, in Chapter 4 we uncovered using a wide range of ex-situ and in-situ techniques several major synergetic effects arising from the iron nanoconfinement and promotion with bismuth and lead on catalytic performance of FT synthesis resulting in light olefins. Iron nanoconfinement inside carbon nanotubes combined with the promotion with Bi or Pb result in a 10-fold higher yield of light olefins. Nanoconfinement in carbon nanotubes mostly leads to better iron dispersion and stability, while intrinsic activity is only slightly affected. Promotion with Bi and Pb results in a major increase in the site intrinsic activity (TOF) in both confined and non-confined catalysts. Over the optimized promoted and confined catalysts, Fischer-Tropsch synthesis occurs under atmospheric pressure with high conversion and enhanced selectivity to light olefins with lower degree of sintering.Apart from the confinement effect, we also study the particle size effect in the confined system for syngas conversion to light olefins over both promoted and unpromoted iron catalysts in Chapter 5. The TOF increases with increasing in the iron nanoparticles sizes from 2.5 to 12 nm over the carbon nanotubes containing encapsulated monometallic or Bi- or Pb-promoted iron nanoparticles. The iron particles size of unpromoted catalysts encapsulated in carbon nanotubes does not show any noticeable effect on the light olefin selectivity, while in the Bi- and Pb-promoted catalysts, the light olefin selectivity was higher over smaller encapsulated iron nanoparticles and decreased with the increase in the nanoparticle size.In Chapter 6, we introduced a new approach for the synthesis of linear α-olefins during low temperature FT synthesis over the Co based catalysts. We found that the co-feeding carboxylic acids leads to a shift of selectivity from paraffins to α-olefins which has been assigned to stabilization of olefins by intermediate formation of esters. The α-olefins selectivity is as high as 39 % in the presence of acids.In the end, we propose a new strategy, which substantially improves the stability of Co and Ni catalysts for CO hydrogenation via their promotion with bismuth. The promoted catalysts demonstrated exceptionally stable performance. The conducted experiments uncovered continuous catalyst self-regeneration during the reaction via oxidation of deposed carbon by oxygen scavenged after CO dissociation at the interface of metal nanoparticles and bismuth promoter. Formation of the bismuth-protecting layer over metal nanoparticles protects them against sintering

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Ahmed, Zaheera. "The use of ruthenium Y zeolite catalysts for the selective methanation of carbon monoxide." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/20032.

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Fuel processing is the conversion of hydrocarbons to produce a mixture of H2 and CO, whereby the H2 will be used in a PEMFC. CO needs to be removed as the tolerance level of the Pt based electro catalyst is only 10 ppm of CO. In order to lower the concentration from 1% post-WGS, to 10 ppm, CO can be converted to CH4 via selective methanation. A selective catalyst primarily methanates CO and inhibits the methanation of CO2 which results in the over consumption of H2. Common catalysts for SMET include Ru/Al2O3 and Ru/Y zeolites. This study involved the use of Ru/Y zeolite catalysts with loadings between 1 wt.%-5.4 wt.% Ru prepared via ion exchange, and a commercial 5 wt.% Ru/Al₂O3. These catalysts were tested in a fixed bed reactor at temperatures between 160°C and 210°C at various space velocities with a feed composition of 1% CO, 20% CO2, 10% H2O, 59% H2 and 10% Ar. The effects of loading, space velocity and reaction temperature on the CO conversion and CO selectivity were investigated. The 2.2 wt.% was found to be the optimum loading by displaying the highest selectivity of 72%, and 100% CO conversion at 170°C. The higher loadings produced large amounts of CH4 displaying lower selectivity, coupled with a high undesirable consumption of H2. The 1 wt.% Ru/Y zeolite showed low activity for SMET but was active for the WGS reaction. The 5 wt.% Ru/Al2O3 displayed the highest selectivity of 60%, and 100% CO conversion at 180°C.

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Nyathi, Thulani Mvelo. "Preferential oxidation of carbon monoxide in hydrogen-rich gases over supported cobalt oxide catalysts." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20547.

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The preferential oxidation of CO (CO-PROX) has been identified as one route of further reducing the trace amounts of CO (approx. 0.5 - 1 vol%) in the H2-rich reformate gas after the high- and low-temperature water-gas shift reactions. CO-PROX makes use of air to preferentially oxidise CO to CO₂, reducing the CO content to below 10 ppm while minimising the loss of H₂ to H₂O. In this study, a Co₃O₄/γ-Al₂O₃ model catalyst was investigated as a cheaper alternative to the widely used noble metal-based ones. The CO oxidation reaction in the absence of hydrogen has been reported to be crystallite size-dependent when using Co₃O₄ as the catalyst. However, studies looking at the effect of crystallite size during the CO-PROX reaction are very few. Metal-support interactions also play a significant role on the catalyst's performance. Strong metal-support interactions (SMSI) in Co₃O₄/Al2o₃ catalysts give rise to irreducible cobalt aluminate-like species. Under CO oxidation and CO-PROX reaction conditions, such strong interactions in a similar catalyst can have a negative effect on the performance of Co₃O₄ but can keep its chemical phase intact i.e., help prevent the reduction of the Co₃O₄ phase. The catalysts used to investigate these two effects (i.e., crystallite size and metal-support interactions) were synthesised using the reverse micelle technique from which nanoparticles with a narrow size distribution were obtained. Certain properties of the microemulsions prepared were altered to obtain five catalysts with varying Co₃O₄ crystallite sizes averaging between 3.0 and 15.0 nm. Four other catalysts with different metal-support interactions were also synthesised by altering the method for contacting the support with the cobalt precursor. The crystallite size of Co₃O₄ in these four catalysts was kept in the 3.0 - 5.0 nm size range.

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Dogbevia, Moses K. "Gas phase transition metal-cluster catalysis /." abstract and full text PDF (free order & download UNR users only), 2005. http://0-wwwlib.umi.com.innopac.library.unr.edu/dissertations/fullcit/3209128.

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Thesis (Ph. D.)--University of Nevada, Reno, 2005.
"August, 2005." Includes bibliographical references. Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm.

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18

Karanjikar, Mukund R. Tatarchuk Bruce J. "Low temperature oxidation of carbon monoxide using microfibrous entrapped catalysts for fire escape mask application." Auburn, Ala., 2005. http://hdl.handle.net/10415/1276.

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19

Gilbank, Alexander. "Ceramic nanostructured catalysts." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648952.

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Catalysis has an effect on almost every aspect of our lives. They are used to help grow the food we eat, clean the water we drink and produce the fuels our civilisation is so dependent upon. Homogeneous catalysts, those in the same phase as the reaction medium, are highly selective as a result of their tuneable nature, for example through changes to ligands in a metal complex. However, their separation from the reaction medium can become a problematic, costly, non-green issue, overcome through the use of heterogeneous catalysts which can be removed and recycled by simple separation techniques such as filtering and sedimentation. A major limitation on understanding the behaviour of heterogeneous catalysts is the presence of different active sites due to different exposed crystal surface, concentration of defects and morphological variations. With such considerations, the first section of this thesis focuses on the synthesis of discrete and well-defined nanostructured materials (ceria and titanate) using a single-step hydrothermal method. Nanostructured ceria with different morphologies (particles, rods and cubes), present a high oxygen storage capacity and thermal stability. Their oxidation catalytic activity was assessed using CO oxidation as a model reaction as a function of their physical and chemical properties, tuned by morphological control at the nanoscale. An inverse relationship is observed between crystallite size and rates of reaction normalised per surface area. Smaller crystallites present a constrained geometry resulting in a higher concentration of defects, highly active catalytically due to their unsatisfied coordination and high surface energy. The surface to bulk oxygen ratio generally increased as the surface area increased, however, ceria nanorods present a higher surface oxygen content than that which would be predicted according to their surface area, likely due to the selective exposure of the (110) and (100) dominating crystal surfaces presenting more facile oxygen atoms in their surface. Additionally a relationship between surface to bulk oxygen ratios and activation energies was also ascribed to the more facile nature of oxygen atoms on these surfaces and their more readily formed oxygen vacancies as a result. This activity is as a result of the formation of oxygen vacancies being the rate-controlling step. The thermal stability of nanostructured ceria (particles, rods and cubes) was also studied to investigate their performance under cyclic high temperature applications. For this, the materials were pre-treated at 1000 °C under different atmospheres (inert, oxidative and reducing). In all cases, the materials sinter, consequently resulting in a dramatic decrease in surface area. Interestingly, their catalytic activity per surface area towards CO oxidation, seems to be maintained, although those materials pre-treated under inert and oxidising atmospheres became inactive in consecutive catalytic runs. However, nanostructured ceria pre-treated at 1000 °C under hydrogen appeared to maintain its activity per surface area. The presence of hydrogen during thermal treatment does not only facilitate the removal of surface oxygen, but also the bulk oxygen, resulting in a rearrangement of the structure that facilitates its catalytic stability. Titanate nanotubes were shown to be inactive for CO oxidation and thus were used in the second part of this thesis as a support for platinum nanoparticles to study the effect of the structure and metal-support interaction on the resulting catalytic activity. The study focuses on the effect of different loading methods (ion exchange and incipient wetness impregnation) of platinum nanoparticles on the resulting metal particle size, dispersion, metal-support interaction and consequently their resulting catalytic activity. Ion exchange consistently resulted in smaller nanoparticles with a lower dispersion of sizes and more active catalyst, both in terms of turnover frequency values and activation energy, compared with incipient wetness impregnation. The catalytic activity of the platinum supported on titanate nanotubes increases as the metal particle size decreases to a size value (between 1 and 2.5 nm) below which a dramatic decrease in activity is observed. Despite initial differences in catalytic activity between the different catalysts, it was observed that after initial reactions to 400 °C, the activation energy was independent of metal loading weight and was instead inherent of the loading method, suggesting the presence of similar active sites.

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Duggan, Michael J. "The use of isotopic oxygen exchange to investigate carbon monoxide oxidation over supported gold catalysts." Thesis, Nottingham Trent University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271214.

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Nyathi, Thulani Mvelo. "Supported Cobalt Oxide Catalysts for the Preferential Oxidation of Carbon Monoxide: An in situ Investigation." Doctoral thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33946.

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The study presented in this thesis has placed great focus on Co3O4-based catalysts for producing CO-free H2-rich gas streams for power generation using proton-exchange or polymer electrolyte membrane fuel cells (PEMFCs). The removal of CO (0.5 – 2%) is essential as it negatively affects the performance of the Pt-based anode catalyst of PEMFCs. Among the various CO removal processes reported, the preferential oxidation of CO (CO-PrOx) to CO2 is a very attractive catalytic process for decreasing the CO content to acceptable levels (i.e.,< 10 ppm) for operating the PEMFC. Co3O4-based catalysts have shown very good catalytic activity for the total oxidation of CO in the absence of H2, H2O and CO2. More specifically, the performance of Co3O4 is known to be influenced by numerous factors such as particle size, particle shape, and the preparation method. As a result, there has also been growing interest in Co3O4 as a cheaper alternative to noble metals for the CO-PrOx reaction. However, the H2 (40 – 75%) in the CO-PrOx feed can also react with O2 (0.5 – 4%) to produce H2O, which consequently decreases the selectivity towards CO2 (based on the total O2 conversion). Aside from H2, the CO-PrOx feed also contains H2O and CO2 which may affect the CO oxidation process as well. The use of Co3O4 as the active catalyst for CO-PrOx can have shortcomings – the main one being its relatively high susceptibility to reduction by H2, forming less active and selective Co-based phases (viz., CoO and metallic Co). Particularly over metallic Co, the conversion pathway of CO can change from oxidation to hydrogenation, forming CH4 instead of CO2. Therefore, the first objective of the work carried out was to investigate the effect of the gas feed components (viz., H2, H2O and CO2; co-fed individually and simultaneously) on the progress of the CO oxidation reaction and the phase stability of Co3O4 over a wide temperature range (50 – 450 °C). It should be noted that the presence of these three gases can also introduce more side reactions, viz., the forward and reverse water-gas shift, respectively, as well as CO and CO2 methanation, respectively. In the supported state, the choice of support, as well as the nature and/or strength of the interaction between the Co3O4 nanoparticles and the support can influence catalytic performance and phase stability. CO oxidation over metal oxides such as Co3O4, is believed to proceed via the Mars-van Krevelen mechanism, which depends on the surface of the catalyst being reducible in order to release lattice oxygen species. Generally, strong metal-support interactions (MSIs) or nanoparticlesupport interactions (NPSIs) can hinder the removal of surface (and bulk) oxygen species, which can negatively affect the catalytic performance. Strong interactions can also promote the solidstate reaction between the species from the nanoparticle with those from the support, leading to the formation of metal-support compounds (MSCs). The supports SiO2, TiO2 and Al2O3 are well known for this phenomenon, and consequently, allow for the formation of silicates, titanates and aluminates, respectively. Support materials such as CeO2, ZrO2 and SiC, are not known for interacting strongly with nanoparticles and often do not react to form MSCs. Therefore, the second objective of this Ph.D. study was to investigate the effect of different support materials (viz., CeO2, ZrO2, SiC, SiO2, TiO2 and Al2O3) on the catalytic performance and phase stability of Co3O4 under different CO-PrOx reaction gas environments. Before carrying out the lab-based experiments, theoretical evaluations were performed by means of thermodynamic calculations based on the Gibbs-Helmholtz Equation. The calculations helped determine the equilibrium conversions of each gas-phase reaction, revealing the extent to which a certain reaction can be expected to take place between 0 and 500 °C. Thermodynamic calculations were also performed to predict the stability of Co3O4, CoO and metallic Co at different temperatures and partial pressure ratios of H2-to-H2O. In the case of supported nanoparticles, the formation of the Co-support compounds - Co2SiO4, CoTiO3 and CoAl2O4 from SiO2, TiO2 and Al2O3, respectively - was shown to be thermodynamically feasible in H2-H2O mixtures. Unsupported Co3O4 nanoparticles were synthesised using the reverse microemulsion technique, while supported Co3O4 nanoparticles were prepared using incipient wetness impregnation. In situ PXRD- and magnetometry-based CO-PrOx catalytic testing was performed in different gas environments as depicted in Figure S.1. The different conditions chosen allowed for the effect of H2, H2O and CO2 on the progress of the CO oxidation reaction and on the reducibility of Co3O4 to be studied. For the first time, this work has identified all the possible gas-phase side reactions (in addition to CO oxidation) that can take place under CO-PrOx conditions. Each reaction could be linked to a specific Co-based phase which is responsible for its occurrence. Furthermore, the temperatures and the extent to which these reactions take place were in-line with the predictions from the thermodynamic calculations. The presence of a support does stabilise the Co3O4 (and CoO) phase over a wide temperature range. Over the weakly-interacting supports (i.e., ZrO2 and SiC), high CO conversions (91.5% and 80.8%, respectively) and O2 selectivities (55.2% and 55.9%, respectively) to CO2 could be obtained, in addition to the improved phase stability of Co3O4. In agreement with the thermodynamic predictions, the presence of Co2SiO4 (7.7%), CoTiO3 (13.8% (from TiO2- anatase) and 8.9% (from TiO2-rutile)), and CoAl2O4 (26.6%) was confirmed using ex situ X-Ray Absorption Spectroscopy in the spent samples of Co3O4/SiO2, Co3O4/TiO2-anatase, Co3O4/TiO2- rutile and Co3O4/Al2O3, respectively, after CO-PrOx. These three samples also exhibited relatively low CO oxidation activities and selectivities, as well as low Co3O4 reducibility.

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Agrell, Johan. "Development of Methanol-Reforming Catalysts for Fuel Cell Vehicles." Doctoral thesis, KTH, Chemical Engineering and Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3669.

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Vehicles powered by proton exchange membrane (PEM) fuelcells are approaching commercialisation. Being inherently cleanand efficient sources of power, fuel cells constitute asustainable alternative to internal combustion engines to meetfuture low-emission legislation. The PEM fuel cell may befuelled directly by hydrogen, but other alternatives appearmore attractive at present, due to problems related to theproduction, transportation and handling of hydrogen.

Fuelling with an alcohol fuel, such as methanol, which isoxidised directly at the anode, offers certain advantages.However, the efficiency of the direct-methanol fuel cell (DMFC)is still significantly lower than that of the conventionalhydrogen-fuelled PEM fuel cell, due to some technical problemsremaining unsolved. Hence, indirect fuelling by a reformedliquid fuel may be the most feasible option in the early stagesof the introduction of fuel cell vehicles.

The work presented in this thesis concerns the developmentof catalysts for production of hydrogen from methanol bypartial oxidation, steam reforming or a combination thereof.The work contributes to the understanding of how thepreparation route affects catalyst morphology and howphysicochemical properties determine catalytic behaviour andreaction pathways.

The thesis is a summary of seven papers published inscientific periodicals. The first paper (Paper I) reviews thecurrent status of catalytic hydrogen generation from methanol,focusing on the fuel cell application. Paper II investigatesthe partial oxidation of methanol over Cu/ZnO catalystsprepared in microemulsion and by a conventionalco-precipitation technique. The activity for methanolconversion in the low-temperature regime is found to besignificantly higher over the former materials and the workcontinues by determining the nature of possible Cu-ZnOinteractions in the catalysts by studying their physicochemicalproperties more thoroughly (Paper III). In Paper IV, thepathways for methanol conversion via both partial oxidation andsteam reforming are elucidated.

In Paper V, partial oxidation of methanol is studied overPd/ZnO catalysts prepared by microemulsion technique and againcompared to conventional materials. This investigationdemonstrates that although possessing high methanol conversionactivity, palladium-based catalysts are not suitable forreforming in fuel cell applications due to the considerableamounts of carbon monoxide formed.

In Paper VI, methanol reforming is investigated over acommercial Cu/ZnO/Al2O3 catalyst. The mechanisms for carbonmonoxide formation and strategies for its suppression arediscussed, as well as reactor design aspects. The study alsoincludes some simple kinetic modelling. Finally, Paper VIIdescribes the optimisation of catalyst composition and processconditions to reach high hydrogen production efficiency at lowoperating temperatures and with minimum carbon monoxideformation.

Keywords:PEM fuel cells, hydrogen, methanol, reforming,(partial) oxidation, reaction pathways, carbon monoxide,catalyst, microemulsion, Cu/ZnO, Pd/ZnO, copper, redoxproperties, oxidation state

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Bouyssy, Pierre X. J. "'1H NMR studies of hydrogen and carbon monoxide chemisorption on the EUROPt-1 catalyst." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367319.

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Ferrandon, Magali. "Mixed metal oxide - noble metal catalysts for total oxidation of volatile organic compounds and carbon monoxide." Doctoral thesis, Stockholm, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3156.

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Kern, Andreas Michael [Verfasser], Bastian J. M. [Akademischer Betreuer] Etzold, and Bastian J. M. [Gutachter] Etzold. "Structured carbon-supported catalysts for methanation of carbon monoxide and dioxide / Andreas Michael Kern ; Gutachter: Bastian J.M. Etzold ; Betreuer: Bastian J.M. Etzold." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2019. http://d-nb.info/1194236391/34.

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Malatji, Peter. "Studies towards degradable polymers new zinc (II) and palladium (II) complexes as catalysts for lactide polymerization and carbon monoxide." Doctoral thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/11137.

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Includes abstract.
Includes bibliographical references.
In this study a range of new zinc and palladium complexes were synthesized, characterized and used in the production of degradable polymers. Zinc complexes were used for the production of polylactides (PLAs) functionalized with a drug candidate on a polymer tail. These functionalized polymers displayed slow drug release properties under physiological conditions. Palladium complexes were utilized for the production of a photodegradable CO/styrene copolymer (CP) which was subsequently reacted with lactide to form a new poly(lactide-co-CO/styrene) block copolymer.

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Saoud, Khaled Mohammad Eqab. "Carbon Monoxide Oxidation on Nanoparticle Catalysts and Gas Phase Reactions of Small Molecules and Volatile Organics with Metal Cations." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/1372.

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This dissertation demonstrates the application of a vapor phase method to synthesize supported and unsupported nanoparticle catalysts for CO oxidation. The method is based on the Laser Vaporization/Controlled Condensation (LVCC) technique. The first part of this dissertation presents the vapor phase synthesis and characterization of gold nanoparticles supported on a variety of oxide supports such as CeO2, TiO2, CuO and MgO.The results indicate that Au nanoparticles supported on CeO2 exhibit higher catalytic activity than Au supported on other oxides. The high activity of the Au/CeO2 catalyst is attributed to the strong interaction of Au with CeO2. The results also indicate that 5% Au loading on CeO2 has higher activity than 2% Au or 10% Au. When comparing the catalytic activity of Au/CeO2 prepared by physical (LVCC) and chemical (deposition-precipitation)methods, it was found that the catalytic activity is higher for Au/CeO2 prepared by the deposition-precipitation method.The effect of alloying Au and Cu nanoparticles on the catalytic activity for low temperature CO oxidation was also investigated. The unsupported Au-Cu alloy nanoparticle catalyst exhibits higher catalytic activity than the activities of the individualcomponents and their physical mixtures. The XRD data of Au-Cu alloy taken after the catalysis test indicates the formation of CuO within the bimetallic nanoparticles, whichimproves the catalytic activity of Au-Cu alloy nanoparticle.The second part of this dissertation investigates the gas phase reactions of Au+ and Cu+ with CO, O2 and H2O molecules using the Laser Vaporization ionization, High-Pressure Mass Spectrometry (LVI-HPMS) technique. The gas phase reactions resulting from the interactions of Au+ with CO and O2 molecules are investigated. Although multiple additions of CO and O2 molecules on Au+ have been observed at room temperature, no evidence was found of the production of CO2. This is attributed to the presence of water molecules which effectively replace the oxygen molecules on Au+ at room temperature.Finally, the role of the metal cations Au+ and Cu+ in initiating the gas phase polymerization of butadiene and isoprene vapors was investigated.

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Yung, Matthew Maurice. "Oxidation catalysis in environmental applications nitric oxide and carbon monoxide oxidation for the reduction of combustion emissions and purification of hydrogen streams /." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1187128442.

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Zhu, Xing. "Development of alkali hexatitanate photocatalysts and co-catalysts for photocatalytic reduction of carbon dioxide by water." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/253386.

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京都大学
0048
新制・課程博士
博士(人間・環境学)
甲第22550号
人博第953号
新制||人||226(附属図書館)
2019||人博||953(吉田南総合図書館)
京都大学大学院人間・環境学研究科相関環境学専攻
(主査)教授吉田寿雄, 教授内本喜晴, 教授田部勢津久
学位規則第4条第1項該当
Doctor of Human and Environmental Studies
Kyoto University
DFAM

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Doughty, P. W. "A study into the performance of catalysts for the hydrocracking of coal extracts under hydrogen and hydrogen/carbon monoxide atmospheres." Thesis, Staffordshire University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382747.

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Iablokov, Viacheslav. "Manganese and cobalt oxides as highly active catalysts for CO oxidation." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209847.

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Durant ce travail de thèse, d’importants paramètres concernant la synthèse de matériaux catalytiques nanostructurés à base de manganèse et d’oxydes de cobalt ont été établis. La corrélation entre les propriétés structurales du catalyseur et l’activité catalytique, ainsi que le mécanisme d’oxydation du CO ont été analysé au moyen d’une grande variété de méthodes expérimentales physico-chimiques.

De l’oxyde de manganèse non-stœchiométrique (MnOx) a été préparé par décomposition spinodale d’oxalate de manganèse trihydraté en ayant recours à la technique d’oxydation programmée en température (TPO). Tant l’analyse quantitative relatives à ces données TPO que les résultats obtenus par spectroscopie de structure au front d’absorption des rayons X (XANES), ainsi que par spectroscopie des photoélectrons X (XPS) ont permis d’estimer la stœchiométrie de l’oxyde avec un x situé entre 1.61 et 1.67. En accord avec à la fois la surface spécifique élevée et la combinaison d’isothermes d’adsorption/désorption de type I et IV, la microscopie électronique à transmission à haute résolution (HRTEM) démontre la présence de micro-bâtonnets caractéristiques et « imbriqués » les uns dans les autres, accompagné de particules nanocristalline à l’extrémité de ces bâtonnets.

Les découvertes faites par spectroscopie infra-rouge de réflexion diffuse par transformée de Fourier (DRIFTS), par études isotopiques et cinétiques suggère que l’adsorption des deux molécules, CO et O2, est suivie par leur réaction en surface via des intermédiaires de type carbonate/formate, pour finalement produire du CO2. Nous supposons un mécanisme de type Mars-van Krevelen où l’oxygène appartenant à la structure de type MnOx prend part dans l’oxydation catalytique du CO à basse température. Cependant, ces espèces mobiles d’oxygènes ne faisaient pas partie du cœur de phase du réseau d’oxyde, et de ce fait, ont été capables de « sauter » sur la surface et approvisionner les espèces oxygénées nécessaires à l’oxydation du CO déjà adsorbé.

Une structure spinelle d’oxyde de cobalt Co3O4 dans lequel le cobalt présente deux états de valence (+2 et +3) a été choisie pour élucider l’effet de la taille des particules sur l’activité lors de la réaction d’oxydation du CO. Tout d’abord, des nanoparticules monodispersées de cobalt métallique présentant une déviation standard en taille inférieure à 8% ont été synthétisées à partir de carbonyle de cobalt (Co2(CO)8) par une méthode optimisée «d’injection chaude». Un contrôle de la taille des nanoparticules dans la gamme 3 à 11 nm a pu être obtenu en variant la température d’injection du carbonyle de cobalt dans une solution de dichlorobenzène et d’acide oléique. La microscopie électronique à transmission (TEM) nous montre que ces particules de cobalt sont quasiment hémisphériques. Ensuite, de la silice poreuse (de type MCF-17) a été imprégnée par des nanoparticules de cobalt, et ensuite activée par TPO menant à des nanoparticules d’oxyde de cobalt. Des études par diffraction des rayons X (XRD) et spectroscopie des photoélectrons X (XPS) ont démontré la structure spinelle Co3O4. Finalement, l’activité des catalyseurs obtenus vis-à-vis de l’oxydation du monoxyde de carbone fut mesurée à 423 K et ce en fonction de la taille des particules. Les particules de Co3O4 présentant une taille allant de 5 à 8 nm se sont révélées les plus actives. Ceci peut s’expliquer par une plus grande mobilité des atomes d’oxygène en surface des nanoparticules d’oxyde de cobalt.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Naumann, d'Alnoncourt Raoul. "The coverage dependent adsorption of carbon monoxide on copper catalysts studied by a combination of adsorption microcalorimetry, temperature programmed desorption and Fourier transform infrared spectroscopy." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975763873.

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Ponsard, Louise. "Conversion catalytique du CO pour la synthèse de monomères oxygénés." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASF002.

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Les produits de l’industrie chimique sont aujourd’hui principalement issus de ressources fossiles non renouvelables. Leur exploitation entraine l’émission de gaz à effet de serre, ayant pour conséquence directe une crise climatique sans précédent. Les petites molécules carbonées (CO et CO₂), aujourd’hui considérées comme des déchets, apparaissent comme des sources attractives de carbone pour assurer la transition de notre économie vers une économie circulaire. Le CO est une petite molécule réactive émise comme déchet par l’industrie chimique, ou pouvant être produite par réduction de CO₂. Une approche visant à utiliser ces deux sources de CO, comme source de carbone pour la synthèse de monomères oxygénés sont envisagées dans ce manuscrit. Au cours de cette thèse, de nouveaux systèmes catalytiques ont été développés pour la formation de nouveaux monomères par carbonylation d’hétérocycles oxygénés. La carbonylation d’époxydes pour la formation de béta-lactones à partir de CO₂ a ensuite été mise au point, grâce à la formation intermédiaire de CO produit par électroréduction du CO₂. La formation d’acide acrylique par isomérisation de la β-propiolactone a ensuite été décrite en conditions douces. Le mécanisme de cette réaction a été élucidé par DFT. Enfin, l’étude d’une réaction de carbonylation de l’acide acrylique a conduit au développement d’une nouvelle méthode pour la synthèse de monomères oxygénés
The production and exploitation of fossil-based chemicals leads to increased emissions of greenhouse gases, responsible for unprecedented climate change. Small molecules (CO and CO₂), currently seen as waste products, could be considered as appealing carbon sources for the transition of our linear economy to a circular economy. Carbon monoxide (CO) is a small molecule released by the chemical industry as gaseous waste, and is accessible through the electroreduction of CO₂. In this manuscript, the utilization of CO from both industrial and electrochemical sources is disclosed, constituting here a carbon source for the synthesis of oxygenated monomers. During this PhD thesis, new catalytic systems were developed for the synthesis of new monomers through the carbonylation of oxygenated heterocycles. The utilisation of CO produced by CO₂-electroreduction in a carbonylation reaction for the synthesis of beta-lactone from epoxides was also shown feasible. The formation of acrylic acid by β-propiolactone isomerisation is reported herein, in mild conditions. The mechanism of this reaction was elucidated by DFT calculations. Finally, the study of the reaction of carbonylation of acrylic acid was proved to be an efficient strategy for the synthesis of oxygenated monomers

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Munakata, Mihou. "Catalytic removal of carbon monoxide in the presence of hydrogen." Thesis, Nottingham Trent University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272668.

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Brown, Steven M. (Steven Michael). "Catalysis and reactor engineering for the electrochemical conversion of carbon dioxide to carbon monoxide." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/124584.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2019
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 163-176).
Carbon dioxide (CO₂) utilization processes have garnered significant interest to both mitigate anthropogenic greenhouse gas emissions and increase the revenue of many chemical and fuel production processes. Low-cost renewable electricity provides impetus for exploring electrochemical methods to recycle CO₂ in cost-competitive and sustainable ways. Researchers have experimentally demonstrated CO₂ transformations into a variety of industrially relevant materials. Techno-economic assessments inform that the simplest transformations, such as generation of carbon monoxide (CO), appear to be the most feasible in the near future. Yet, widespread commercialization of this nascent technology has not occurred due to a number of challenges that include synthesizing stable and active catalyst materials, understanding activity-Ưdriving force relationships, identifying appropriate reactor configurations, and developing comprehensive process models.
This thesis advances both the experiment and theory of CO₂ conversion to CO through electrocatalysis and reactor engineering. A flow reactor was designed and manufactured to understand CO2 reduction in ways that traditional, batch, electroanalytical devices cannot. A key advantage is that, through the use of porous carbon electrodes, the reactor converts gaseous CO₂ to CO at the catalyst-electrolyte interface in a continuous fashion, alleviating the mass transport limitations common to liquid-phase CO₂ delivery systems. To facilitate this transformation, a carbon-supported gold nanoparticle catalyst was synthesized and deposited onto gas diffusion electrodes. These nanoparticles achieved high selectivity (>90%) to CO formation over the competing hydrogen evolution side reaction.
Traditional electrokinetic analyses (e.g., Tafel) were largely unsuccessful at describing the observed current-potential relationship, prompting a rigorous follow-up study on electrokinetics wherein Marcus theory and mass transport convolution, amongst other considerations, were explored. Bayesian statistics concluded that, despite the ubiquitous implementation of Butler-Volmer kinetics in literature, in actuality, a Marcus-Hush-Chidsey model provides the most accurate description of the electrochemical reduction of CO₂ to CO. The implications of this result are significant, potentially resulting in order of magnitude differences in current density projections at high overpotentials.
Overall, this thesis experimentally measured catalysis rates in a specialized electrochemical flow cell, unimpeded by mass transport, and leveraging these results, as well as those from prior literature, advanced electrokinetic descriptions of CO₂ conversion all towards furthering the commercial prospects of this electrochemical technology.
by Steven M. Brown.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Chemical Engineering

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Cox, Alison Sarah Jane. "Development of a nickel-cobalt oxide catalyst for carbon monoxide oxidation." Thesis, University of Essex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392691.

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Idriss, Hicham. "Etude des especes de surface sur catalyseurs cu-zn dans la synthese du methanol." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13071.

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Sun, James T. "Catalysed methanol synthesis from carbon dioxide, carbon monoxide and hydrogen over Cu/ZnO/Al2O3." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/11470.

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Moore, Nichola Sian. "Studies of nickel (II) diphosphine complexes directed towards carbon monoxide/ethene catalysis." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4832/.

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The thesis is concerned with the synthesis, characterisation and reactivity of a variety of nickel(II) diphosphine complexes considered possible catalyst precursors for the copolymerisation of CO and ethene. [Ni(diphos)(o-tolyl)(py)]Y (1), [Ni(diphos)(_2)](Y)(_2) (2), and [Ni(diphos)(S)(_2)](Y)(_2) (3) {Y = OTs, OTf} are found to be catalyst precursors for the CO/ethene reaction (115 C, 1200psi, 1:1 CO: ethene) with high selectivity to polyketone formation, the activity depending on the phosphine ligand employed. However, the activity is low and attributed in part to the formation of the [Ni(diphos)(CO)(_2)] (4) complexes which are stable under the reaction conditions. The diphosphine hgand employed, particularly the nature of the backbone, is found to influence the synthesis and reaction chemistry of the complexes (1), (2) and (3).A series of complexes of the type [Ni(R(_2)P(CH(_2))(_a)PR(_2))(o-tolyl)Br] (5) {n = 2; R = Ph, Cy, 'Bu) have been synthesised and the complex [Ni(dppe)(o-tolyl)Cl] has been characterised by X-ray crystaliography. The influence of the chelating diphosphine on the structural characteristics and NMR parameters of these compounds has been investigated. When n > 2 the complexes of the type [Ni(diphos)(o-tolyl)X] were not isolated. The reaction of type (5) complexes with TIY (Y = OTs, BF(_4)) in pyridine led to the formation of complexes of the type [Ni(diphos)(o-tolyl)(py)]Y (1).A series of complexes of the type [Ni(diphos)Cl(_2)] (6) {diphos = dope, dBpe, dcpn} have been synthesised and characterised by X-ray crystallography. The influence of the chelating phosphine ligand on structural characteristics of these compounds has been investigated. Complexes of the type (2) and (3) can be synthesised from type (6) complexes. Detailed studies on the behaviour of a series of complexes of the type [Ni(diphos)(_2)](Y)(_2) (2) and [Ni(diphos)(Y)(_2)] (3) {Y = OTs and OTf), and the equilibrium between them in solution have been undertaken. The complex [Ni(dppe)(-2)](OTs)(_2) has been characterised by X-ray crystallography.

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Zacchini, Stefano. "Spectroscopic studies of palladium catalysed reactions between carbon monoxide and ethene." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343704.

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Jayasree, Baby. "Low temperature catalytic liquid phase water gas shift reaction for carbon monoxide free hydrogen generation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/198834.

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Cornilleau, Thomas. "Développement de nouvelles molécules plateformes pour le marquage par du monoxyde de carbone : applications en imagerie par Tomographie d'Emission de Positions (TEP) et imagerie bimodale TEP/optique." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0146/document.

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La Tomographie par Emission de Positrons (TEP) constitue l’une des techniques d’imagerie moléculaire les plus novatrices pour la visualisation in vivo des processus biologiques. Elle intervient comme technique de choix pour le diagnostic dans de nombreux domaines. La conception et l’élaboration de nouveaux radiotraceurs sont en perpétuel développement. Dans ce contexte une méthode d’introduction du radioisotope 11C a été développée pour le marquage de composés bioconjugées. Les conditions particulièrement douces de l’alcoxycarbonylation intramoléculaire mise au point ont permis un marquage en dernière étape de synthèse. La diversification des structures des précurseurs a également été envisagée grâce à un nouveau couplage biarylique catalysé à l’or sous conditions photorédox. Enfin la fonctionnalisation de motifs BODIPY a conduit à de premières avancées pour l’obtention de sondes bimodales innovantes
Positron Emission Tomography (PET) is a powerful molecular-imaging technique for physiological andbiological investigations in various areas. Due to the increasing need of this technique for in vivoapplications, there is always a demand for the development of new tracers and radiolabelingstrategies. In this context an original method was developed to introduce the 11C-radioisotope for thelabeling of bioconjugated compounds. The extremely mild conditions of this intramolecular Pdcatalyzedalcoxycarbonylation allowed to label these structures in the last step of the synthesis.Diversification of the available precursors was investigated by a novel biaryl cross coupling using goldcatalisis under photoredox conditions. Finally, preliminary studies for the functionalization of BODIPYcores were realized to obtain innovative bimodal probes

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Payne, Martin William. "Investigation of the reactivity of [HM?(CO)??]? (M = Ru, Os) clusters : kinetics of ¹³CO exchange, effects of ion pairing, and the relationship between the ¹³CO exchange and the catalysis of the water-gas shift reaction /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487332636477575.

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Tabey, Alexis. "Synthèse de nouveaux complexes aryl-palladium et aryl-or pour le marquage par du monoxyde de carbone de composés bioconjugués supportés et pour des réactions de couplages." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0025/document.

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L’essor de la chimie organométallique a permis de développer de nouvelles possibilités dans le domaine du diagnostic médical, en particulier pour la tomographie à émission de positrons (TEP). Ainsi, de nouvelles méthodologies ont été développées pour permettre la synthèse de bio-traceurs avec le marquage au 11C comme étape finale. Dans ce contexte, notre équipe a récemment développé une nouvelle méthodologie pour marquer une large variété de substrats dans des conditions standards de carbonylation et ces travaux de thèse présentent une nouvelle stratégie de synthèse impliquant la préformation de complexes palladiés supportées. Ainsi, leurs ancrages préalables sur une résine facilitent la réaction de carbonylation en simplifiant leur purification. De nouveaux complexes à base de palladium ont aussi été synthétisés et étudiés pour envisager de potentielles applications en catalyse photorédox. Enfin le développement de nouvelles stratégies de couplage impliquant des intermédiaires d’or (III) étant un domaine en plein expansion, notamment lorsqu’elles combinent catalyse à l’or et photorédox, il a été envisagé de synthétiser de nouveaux complexes d’or afin d’étudier les mécanismes réactionnels impliqués dans ces couplages et d’évaluer les possibilités de synthèse de composés biaryliques atropoisomériques
The growth of organometallic chemistry has allowed numerous developments in the field of medical diagnosis, especially for Positron Emission Tomography (PET). Developing new methodologies for the synthesis of biological tracers by a last-step 11C labeling, our team has been recently able to take advantage of the great functional tolerance of palladium-catalyzed carbonylation to achieve this goal. A new synthetic strategy involving preformed palladium complexes is described in this manuscript. Their anchoring on a polystyrene resin allowed subsequently to facilitate the carbonylation process by simplifying the purification. New palladium complexes have also been investigated for their potential photoredox applications. Finally, new coupling strategies implying gold (III) intermediates and photoredox catalysis being a very attractive subject, new gold complexes have been synthetized in order to investigate the reaction mechanisms that could operate. Possibilities of asymmetric induction in the synthesis of atropoisomeric biaryl compounds were also studied

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He, Shiyu. "Synthesis of New Zwitterionic Nickel(II) Catalyst For Ethylene and Carbon Monoxide Copolymerization." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1524763348307418.

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46

Bouhatmi, Marième. "Dépollution de l'habitacle automobile par photocatalyse et catalyse d'oxydation à froid." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1036.

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L’automobile étant le premier moyen de déplacement en France, la présence de Composés Organiques Volatils (COVs) et de monoxyde de carbone à l’intérieur de l’habitacle, constitue un problème de santé publique. Plusieurs systèmes de dépollution, basés sur des méthodes d'adsorption, existent sur le marché, mais ne permettent qu'une simple rétention des COVs en surface. Parallèlement, des méthodes moins conventionnelles telle que la photocatalyse utilisant le dioxyde de titane, permettent d'oxyder les COVs sous irradiation, en présence d'humidité et à température ambiante. Cependant, la photocatalyse ne permet pas l’oxydation de certains polluants comme le monoxyde de carbone sans ajout de co-catalyseur. Pour éliminer le CO, la catalyse d’oxydation à froid sur dioxyde de manganèse a été étudiée.L’objectif de cette thèse est de développer une solution économique permettant la dépollution de l’habitacle automobile. Ce projet vise à allier à terme l’oxydation photocatalytique d’un COV modèle le n-pentane sur TiO2 P25 et l’oxydation catalytique du monoxyde de carbone à température ambiante sur des MnO2 synthétisés. En photocatalyse, les résultats mettent en évidence que la vitesse de dégradation diminue avec le taux d’humidité relative et augmente avec la puissance lumineuse et la concentration en n-pentane. Les concentrations des intermédiaires réactionnels sont de l’ordre du ppbv pour des ppmv de n-pentane injectés. L’operando DRIFTS a mis en évidence la présence de carbonates à la surface du photocatalyseur. Parallèlement, les expériences de PTR-MS-TOF-SRI et GC-MS ont permis d’identifier la présence de composés carbonylés parmi lesquels du formaldéhyde et la pentan-2-one. Ces intermédiaires ont permis de proposer un mécanisme de la dégradation du n-pentane sur TiO2 P25. Il a également été démontré que l’oxydation photocatalytique du n-pentane par TiO2 P25 permet une minéralisation pratiquement complète quelles que soient les conditions de travail. Pour le système catalytique, des oxydes de manganèse ont été synthétisés par co-précipitation puis calcinés sous oxygène à trois différentes températures : 100°C, 200°C et 300°C. Les performances catalytiques pour l’oxydation du CO ont été évaluées à température ambiante en l’absence d’humidité relative. Des méthodes en température programmée (TPD, TPO, TPR) ont permis de caractériser l’impact de la température de calcination sur la surface du dioxyde de manganèse. Les caractérisations DRX et BET ont mis en évidence la formation de la phase γ-MnO2 stable de 100°C à 300°C et de grande surface spécifique (178-197 m²/g). Les résultats montrent que les catalyseurs permettent une oxydation du monoxyde de carbone à température ambiante. Le catalyseur calciné à 100°C (MnO2-100) présente les meilleures performances avec un taux de conversion initiale de 60% à température ambiante pour 500 ppmv de CO à 10 L/h, 20%O2, (VVH = 25 000 h-1). Les catalyseurs, notamment MnO2-100, se désactivent au cours du temps à température ambiante. Cette désactivation pourrait être due à la capacité du catalyseur à renouveler ses oxygènes du réseau, impliquer dans le processus catalytique
The presence of Volatile Organic Compounds (VOCs) and carbon monoxide in indoor air is a major health issue. The vehicle cabin air is also affected by this problem, being the first mode of transportation. Most of the current depollution systems are based on trapping using adsorption methods, while photocatalytic processes offer the potential to fully degrade VOCs at room temperature in presence of relative humidity. However, carbon monoxide cannot be degraded by photocatalysis without a co-catalyst. Consequently, the room temperature oxidation catalysis of carbon monoxide has been studied. This thesis aims to develop an economical solution for cleaning the vehicle cabin air. This solution is based on crossing the photocatalytic oxidation of a target molecule the n-pentane over by TiO2 P25 and the room temperature oxidation of CO over synthesized MnO2. Results show that the n-pentane degradation rate decreases with the humidity level, and linearly increases with the irradiance power and the VOC concentration. Intermediates species are lowed concentrates (ppbv order) for ppmv of n-pentane used. Operando DRIFTS experiments highlighted the presence of formates surface species during the photocatalytic degradation of n-pentane. PTR-MS-TOF-SRI and GC-MS experiments highlighted the presence of carbonyl compounds as formaldehyde and pentan-2-one in gas phase during the degradation. Those intermediates species allowed us to propose a mechanism for the photocatalytic oxidation of n-pentane over TiO2 P25. Moreover, the efficiency of the photocatalytic degradation of n-pentane over TiO2 has been proved given that an almost complete mineralization is obtained whatever the working conditions. In catalysis, manganese oxides were synthesized by a co-precipitation method then calcined under oxygen at three different temperature: 100°C, 200°C and 300°C. The catalyst performances were evaluated for CO oxidation at room temperature in dry conditions. Temperature programmed methods were used for probing the impact of the calcination temperature on the catalyst surface. DRX and BET characterizations confirmed the formation of the phase γ-MnO2 stable between 100°C and 300°C, and a large surface area (178-197 m²/g). Results highlighted that the synthesized catalysts can oxide the CO at room temperature. The catalyst calcined at 100°C (MnO2-100) show the best performances with an initial conversion rate of 60% for 500 ppmv CO, at 10 L/h at 20% O2 (VVH = 25 000 h-1). However, a deactivation over the time of all the catalysts was observed, especially for MnO2-100. This deactivation could be related to the capacity of the catalyst to renew the oxygen bulk implied in the catalytic process

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47

Mennour, Ammar. "Caracterisation par spectroscopie infrarouge d'alumines modifiees et de catalyseurs w(mo) - ni(co) sulfures supportes sur alumine." Caen, 1987. http://www.theses.fr/1987CAEN2019.

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48

Foster, Carina Elizabeth. "Reactions of [FeFe]-hydrogenase with carbon monoxide and formaldehyde." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:a1d43c4a-861a-4bb0-88ce-2edf4c334f79.

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The use of H2 as an energy carrier has in recent years been identified as a promising future solution to the current energy crisis. Hydrogenases are metalloenzymes found in many microorganisms and are used to catalyse the reversible inter-conversion of protons and H2. These enzymes and their synthetic analogues have been recognised as a way to facilitate the use of H2 as a fuel. A major challenge to the future use of these catalysts is their reactions with small molecule inhibitors, such as oxygen and carbon monoxide. Detailed understanding of the structure and catalytic mechanism of these highly efficient catalysts is vital for the design of bio-inspired functional analogues for use in technological applications. In this thesis electrochemical studies of three [FeFe]-hydrogenases are presented, performed using the technique of protein film electrochemistry. The strong potential dependence of the reaction of these hydrogenases with carbon monoxide and formaldehyde is characterised and rationalised. These studies provide compelling evidence for the formation of a previously ambiguous super-reduced state of [FeFe]-hydrogenase at low potential. This state is shown to be active and stable, and it is proposed that this state is involved in catalytic H2 production. This super-reduced state is shown to have a high affinity for the reversible binding of formaldehyde, but a very low affinity for both carbon monoxide and oxygen. Activation of carbon monoxide inhibited [FeFe]-hydrogenase can be very rapidly induced by the application of a sufficiently reducing potential. These enzymes, considered to be oxygen sensitive, are shown to be extremely tolerant to irreversible oxygen damage at very reducing potentials where the super-reduced state is formed.

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49

Li, Maohua. "Synthesis of Polyketones from Zwitterionic Nickel Compound Catalyzed Copolymerization of Carbon Monoxide And Olefins." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1461772542.

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50

Luke, Ronald John Campbell. "The reversible electrochemical promotion of the catalytic oxidation of carbon monoxide over platinum supported yttria-stabilised zirconia." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243861.

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Dissertations / Theses on the topic 'Carbon monoxide Catalysts'

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