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Promoted Co-CNT nano-catalyst for green diesel production using Fischer-Tropsch synthesis in a fixed bed reactorTrepanier, Mariane 20 September 2010 (has links)
This research project is part of a larger Canadian endeavour to evaluate feasibility of using new nanocatalyst formulations for Fischer-Tropsch synthesis (FTS) to convert fossil-derived or renewable gaseous fuels into green diesel. The green diesel is a clean fuel (with no aromatics and sulfur compounds) suitable for the commonly used transportation system. The catalyst investigated is cobalt metal supported on carbon nanotubes (CNTs). The physical properties of CNTs have improved the common cobalt catalyst currently used in industry. Carbon nanotubes have high surface area, a very stable for FTS activity and, contrary to other common supports, do not interact with the catalyst active phase to produce undesirable compounds. Moreover, CNTs differ from graphite in their purity and by their cylindrical form, which increases the metal dispersion and allows confinement of the particles inside the tubes. Thus, carbon nanotubes as a new type of carbon material have shown interesting properties, favoring catalytic activity for FTS cobalt catalyst. Their surface area can be modified from 170 to 214 m^2/g through acid treatment. The CNT support lowers the amount of Ru promoter needed to increase the catalyst activity up to 80 % CO conversion and potassium promoter increases the selectivity for á-olefins. The olefin to paraffin (O/P) ratio for Co/CNT and CoK/CNT are 0.76 and 0.90, respectively. Moreover, the Co-Fe bimetallic catalysts supported on CNT have proved to be much more attractive in terms of alcohol formation, up to 26.3 % for the Co10Fe4/CNT. The structural characteristics of CNTs have shown to be suitable for use as catalytic support materials for FTS using microemulsion preparation method as applied to produce nanoparticle catalysts. Microemulsion technique results show uniform nanoparticle that are easy to reduce. In addition, the confinement of the particles inside the CNT has improved the lifetime of the catalyst by decreasing the rate of sintering. The deactivation rate at high FTS activity is linear (XCO = -0.13 t(hr) + 75) and at low FTS activity is related to a power law expression of order 11.4 for the cobalt particles outside the tubes and 30.2 for the cobalt particles inside the tube. The optimized catalyst studied was the CoRuK/CNT catalyst. The best kinetic model to describe the CoRuK/CNT catalyst is: 18.5 x 10 ^-5 PH2^0.39/ (1 + 7.2 10 ^-2 PCO^0.72 PH2^0.1)^2.
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Synthesis, Characterization and Crystal Structures of Organometallic Compounds Containing Cyclotetradeca-1,8-diyne and Bis(diphenylphosphino)nonadiyne LigandsShiue, Tsun-Wei 03 September 2005 (has links)
none
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Synthesis of Triosmium Clusters Containing 1,8-Cyclotetradecadiyne LigandXue, Guang-Cheng 13 August 2002 (has links)
none
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Synthèse de liaisons carbone-carbone via l'utilisation d'une catalyse par des complexes du cobaltAmatore, Muriel Gosmini, Corinne. January 2006 (has links) (PDF)
Thèse de doctorat : Chimie organique : Paris 12 : 2006. / Version électronique uniquement consultable au sein de l'Université Paris 12 (Intranet). Titre provenant de l'écran-titre. Pagination : 231 p. Bibliogr. : 328 réf.
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Complexes de cuivre, nickel et cobalt avec des ligands polyazotés pentadentés linéaires et heptadentés tripodes amido-pyridiniques et pyraziniques: synthèses, études thermodynamiques et structuralesHubert, Sandrine Gérard, Christian Mohamadou, Aminou. January 2007 (has links) (PDF)
Reproduction de : Thèse doctorat : Chimie : Reims : 2007. / Titre provenant de l'écran titre. Bibliogr. f. 131-134.
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Mode de fonctionnement du cobalt dans l'hydroformylation des alcènes catalysée par le système {[Co2(CO)8]/Pyridine/Liquide Ionique}Hébrard, Frédéric Kalck, Philippe. Olivier, Hélène January 2006 (has links)
Reproduction de : Thèse de doctorat : Chimie organometallique et de coordination : Toulouse, INPT : 2006. / Titre provenant de l'écran-titre. Bibliogr. dans le corps du texte.
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Spin-dependent tunneling into single cobalt-phthalocyanine moleculesIacovita, Cristian Bucher, Jean-Pierre. January 2009 (has links) (PDF)
Thèse de doctorat : Physique de la matière condensée : Strasbourg : 2009. / Titre provenant de l'écran-titre. Notes bibliogr.
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Réseaux bidimensionnels d'agrégats magnétiques préformés en phase gazeuseHannour, Abdelkrim Prével, Brigitte Bardotti, Laurent January 2007 (has links) (PDF)
Reproductin de : Thèse de doctorat : Physique de la matière condensée : Lyon 1 : 2007. / Titre provenant de l'écran titre. 190 réf. bibliogr.
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Lithium-ion battery cathodes : structural and chemical stabilities of layered cobalt and nickel oxides /Chebiam, Ramanan Venkata, January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 161-171). Available also in a digital version from Dissertation Abstracts.
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Ligand substitution kinetics and mechanisms of some cobalt (III) complexes containing macrocyclic Schiff-base amines.Liao, Sau-tung, Sarah, January 1977 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1977.
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