Dissertations / Theses: 'Oxidation coupling of methane'

1

Zhang, Yi Qun. "Methane oxidative coupling over fluoride/oxide catalysts : a dissertation." HKBU Institutional Repository, 1993. http://repository.hkbu.edu.hk/etd_ra/15.

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2

Hargreaves, J. S. J. "The catalysed oxidative coupling of methane." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303659.

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3

Chung, Elena Yin-Yin. "Investigation of Chemical Looping Oxygen Carriers and Processes for Hydrocarbon Oxidation and Selective Alkane Oxidation to Chemicals." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469182957.

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4

Lapena-Rey, Nieves. "Oxidative coupling of methane in ceramic electrochemical reactors." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394407.

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5

Tsang, S. C. "An investigation of the catalytic oxidative coupling of methane." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277111.

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6

Serres, Thomas. "Oxidative Coupling of Methane followed by Oligomerization to Liquids." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10229.

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Les importantes réserves de gaz naturel – avérées ou potentielles – font de cet hydrocarbure un substitut plausible du pétrole pour la production d'hydrocarbures liquides. Cependant la plupart des réserves de gaz découvertes à l'heure actuelle sont de taille réduite et dispersées loin des sites de transformation ou de consommation. Le couplage du réformage (RM) et du couplage oxydant du méthane (OCM) dans un réacteur à microcanaux permettrait de rendre viable l'exploitation de ces réserves grâce à des coûts opératoires de transformation du gaz naturel réduits par rapport aux usines actuelles. De plus, l'utilisation de ce type de réacteurs compacts réduirait fortement la taille des usines de transformation du méthane. L'intégration de réactions de réformage du méthane en microréacteur a déjà été étudiée et des systèmes stables et performants ont été développés. En revanche, aucune étude n'a été faite sur le comportement de l'OCM dans ces réacteurs. Il a cependant été prouvé que ce procédé est basé sur un équilibre sensible entre réactions de surface et réactions en phase gazeuse. Or l'efficacité thermique des microréacteurs est liée au très grand rapport surface sur volume de gaz au sein des microcanaux par rapport à des réacteurs en lit fixe. L'étude présente de l'influence de la conception des réacteurs sur les performances du système OCM montre qu'une contribution trop importante de la surface catalytique est négative pour l'activité et la sélectivité des catalyseurs OCM. La comparaison des catalyseurs en poudre ou en revêtement a montré que seule la géométrie des réacteurs – soit le rapport volume de phase gaz sur surface catalytique (rapport V/S) – avait une influence sur les performances du système catalyseur + réacteur. L'utilisation de ce paramètre montre en effet que le type du réacteur choisi n'a aucun effet sur les performances de la réaction d'OCM à rapport V/S constant. L'influence positive d'une augmentation du rapport V/S sur les performances du système est en revanche limitée à cause de la faible durée de vie des radicaux en jeu dans l'OCM. L'utilisation du paramètre V/S a en revanche permis d'estimer la géométrie idéale des canaux d'un microréacteur à travers leur diamètre. Deux types très distincts de catalyseurs OCM ont été sélectionnés pour cette étude, conduisant soit à une activité réduite mais une plus grande sélectivité en éthylène soit l'inverse selon la composition et la structure/texture de ces catalyseurs. Au maximum de leurs productivités en éthylène respectives, le catalyseur au lanthane présente une productivité quatre fois plus importante que le catalyseur basé sur le système Mn-W-Na. La différence d'activité des deux catalyseurs étudiés peut s'expliquer par la densité en site actifs de chaque catalyseur. Celui au lanthane est uniquement constitué d'éléments actifs (La, Sr and Ca) contrairement au catalyseur Mn-W-Na dont la surface est en partie constituée de silice inerte. De plus le système Mn-W-Na présente des surfaces spécifiques en général cinq fois inférieures au catalyseur au lanthane. Cependant, les sites actifs du catalyseur au lanthane ne sont pas tous sélectifs envers la production de C2 et sont en revanche très actifs envers la production de précurseurs de COx. Un catalyseur OCM idéal associerait donc la densité de sites actifs du catalyseur au lanthane avec la sélectivité des systèmes Mn-W-Na. La concentration en éléments actifs pour ce système Mn-W-Na a donc été augmentée progressivement. Il s'est avérée que cette augmentation améliorait l'activité de ces catalyseurs par rapport à ceux référencés dans la littérature mais que l'amélioration était limitée au-delà d'une certaine concentration. deux fois inférieure à celle du catalyseur au lanthane soit quatre fois plus importante que le catalyseur référencé dans la littérature [etc…]

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7

Graf, P. O. "Combining oxidative coupling and reforming of methane vision or utopia? /." Enschede : University of Twente [Host], 2009. http://doc.utwente.nl/60460.

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8

Driscoll, Sharon Anne. "Oxidative coupling of methane over alkali-promoted manganese molybdate catalysts /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847761306923.

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9

He, Hong. "The oxidative coupling of methane over BaX2/La2O3, LaOX, and BaCO3/LaOX (X=halogen) catalysts." HKBU Institutional Repository, 1996. http://repository.hkbu.edu.hk/etd_ra/58.

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10

Hamid, Hamzah b. Abd. "Oxidative coupling of methane on samaria and on mixed oxide catalysts." Thesis, University of Hull, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335155.

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11

Zhang, Xiankuan. "Studies of methane oxidative coupling with practical catalysts and model systems." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386819.

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12

Liu, Yiwei. "The catalytic performance and characterization of BaO- and BaX2(X=F, Cl, Br)-promoted Ln2O3(Ln=Y, Er, Nd) catalysts for the oxidative coupling of methane." HKBU Institutional Repository, 1998. http://repository.hkbu.edu.hk/etd_ra/176.

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13

Fleischer, Vinzenz [Verfasser], Reinhard [Akademischer Betreuer] Schomäcker, Ulrich [Gutachter] Nieken, Robert [Gutachter] Schlögl, and Reinhard [Gutachter] Schomäcker. "Oxidative coupling of methane : resolution of the surface and gas phase contributions to the mechanism of the oxidative coupling of methane at Na2WO4-Mn-SiO2-catalyst / Vinzenz Fleischer ; Gutachter: Ulrich Nieken, Robert Schlögl, Reinhard Schomäcker ; Betreuer: Reinhard Schomäcker." Berlin : Technische Universität Berlin, 2017. http://d-nb.info/1156346746/34.

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14

Salerno-Paredes, Daniel [Verfasser], and Günter [Akademischer Betreuer] Wozny. "Optimal Synthesis of Downstream Processes using the Oxidative Coupling of Methane Reaction / Daniel Salerno-Paredes. Betreuer: Günter Wozny." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1031280235/34.

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15

Jašo, Stanislav [Verfasser], and Günter [Akademischer Betreuer] Wozny. "Modeling and Design of the Fluidized Bed Reactor for the Oxidative Coupling of Methane / Stanislav Jašo. Betreuer: Günter Wozny." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1028912943/34.

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16

Paloschi, Rozileia Simoni. "Acoplamento não oxidativo de metano sobre metais suportados em solidos microporosos." [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267578.

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Orientador: Gustavo Paim Valença
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-07-31T19:58:48Z (GMT). No. of bitstreams: 1 Paloschi_RozileiaSimoni_M.pdf: 2623823 bytes, checksum: 569787d9b56d1368559be20011050e5e (MD5) Previous issue date: 2002
Resumo: A conversão catalítica de metano para combustível liquido ou outros produtos químicos é de grande interesse e muitas tentativas de utilização têm sido feitas para ativar metano em condições não oxidativas e convertê-lo em hidrocarbonetos grandes e compostos aromáticos. Neste trabalho, duas zeólitas H-ZMS-5 com razões Si/AI diferentes e uma zeólita H-Y foram impregnadas com 3% p/p de Mo e testadas na reação de acoplamento não oxidativo de metano. Análises de DRX e FTIR demonstraram que o Mo está bem disperso na superfície nos canais das zeólitas. A área superficial BET e o volume de poros apresentaram uma pequena redução após a impregnação. As reações foram feitas a 973 K. O catalisador Mo/H-Y só apresentou CO e H2 como produtos. O catalisador MO/H-ZSM-5 com a zeólita de menor razão Si/AI apresentou a maior conversão de metano e seletividade à benzeno quando a reação foi realizada em condição de baixa velocidade espacial de metano. A adição de 40% de H2 não favorece a formação de hidrocarbonetos C2 e aromáticos, enquanto a adição de apenas 10% resultou em um aumento na estabilidade da conversão de metano, especialmente para a zeólita com menor razão Si/AI. A adição de 20% de H2 resultou em menor conversão de metano e seletividade a benzeno quando comparada às reações sem adição de co-reagente e com 10% de co-reagente. Foram feitas também reações a 923 K e 1023 K para a determinação da energia de ativação. O catalisador 3Mo/H-ZSM-5 com menor razão Si/AI desativou completamente após 13 h de reação, enquanto o catalisador 3Mo/H-ZSM-5 com maior razão Si/AI desativou completamente após 9 h de reação. Este último foi regenerado por passagem de oxigênio à temperatura entre 723 e 823 K e testado novamente na reação de acoplamento não oxidativo de metano, apresentando valores de conversão de metano e seletividade à benzeno equivalentes aos observados na reação com o catalisador não regenerado
Abstract: The catalytic conversion of methane to liquid fuels or commodity chemicals is an attactive process that has received a great dela of attention recently. The conversion of methane under nonoxidative conditions results in longer chain hydrocarbons and aromatics compounds. In this work, two H-ZSM-5 zeolites with different Si/AI ratios and one H-Y zeolite were loaded with 3wt% Mo. They were used as catalysts in the reaction of nonoxidative coupling of methane. XRD and FTIR analysis showed that the molybdenum species are uniformly distributed on the surface in the channels of the zeolites. The BET surface area and the pore volume decreased slightly after impregnation with Mo. The reactions were carried out at 973 K. The only products for the Mo/H-Y smaples were CO and H2. The methane conversion and selectivity to benzene were higher for the Mo/H-ZSM-5 catalyst with lower Si/AI ratio and for lower methane space velocity. The nonoxidative coipling of methane reaction did not occur when 40% hydrogen were added to the methane feed stream. However, the methane conversion became stable and increase as 10% hydrogen were added to methane. This was true for the zeolite with lower Si/AI ratio. When 20% hydrogen were added to the methane feed stream, the methane conversion and selectivity to benzene were lower than when 10% hydrogen or no hydrogen were added to the feedstream. Reactions were carried out at 923 and 1023 K in order to determine the activation energy. The activation energy values were similar fo the reaction on the zeolites with different Si/AI ratios. The catalyst with lower Si/AI ratio deactivated after 13 h and the catalyst with higher Si/AI ratio deactivated after 9 h on stream. The catalyst with higher So/SI ratio was regenerated by flowing oxygen at temperatures between 723 and 823 K. After regeneration the catalyst had the same catalytic performance as the ¿fresh¿ catalyst
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

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17

Meyer, Katja Elizabeth. "Perovskite-type Oxides as Electrocatalysts in High Temperature Solid Electrolyte Reactor Applications." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1493821638601215.

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18

Kwapień, Karolina. "Active sites for methane activation in MgO and Li doped MgO." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16497.

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Die vorliegende Dissertation präsentiert eine detaillierte quantenchemische Untersuchung der H-Abstraktion von Methan durch MgO und Li dotiertes MgO. Motiviert wurde die durch das UniCat-Excellenz-Cluster, welches sich zum Ziel gesetzt hat, die oxidative Kupplung von Methan (OCM) im Detail zu verstehen. Basierend auf der Hypothese, dass Li+O•– Spezies für den H-Abstraktion Schritt verantwortlich sind, wurden kleine kationische MgO- und Li dotierte MgO-Cluster (die O•– Sites modellieren) untersucht. Zur Erstellung von möglichst realen Gasphasen-Modell-Systemen, wurde die globalen Minima der Gasphasencluster mittels eines genetischen Algorithmus bestimmt. Zum Vergleich wurden auch die Strukturen von neutralen MgO-Cluster bestimmt, um eventuelle strukturelle Unterschiede zu erkennen. Anschließend wurden die optimierten Cluster in Bezug auf ihre Eignung zur C-H-Bindungsaktivierung von Methan untersucht. Die Verwendung von kleinen Cluster-Größen ermöglicht es, die Reaktion im Detail zu studieren und verschiedene Methoden der Berechnung zu vergleichen. Die Ergebnisse für die kleinen Cluster wurden anschließend mit realistischeren Modellen verglichen, die eine genauere Beschreibung der Li dotierten Oberflächen ermöglichen, wie zum Beispiel non-embedded und embedded-Cluster und slab Modelle. Unerwartete Ergebnisse für die Betrachtung der Li+O•– Spezies haben zur Untersuchung von zusätzliche Arten von Defekten in MgO (wie niedrig koordinierten O2-Seiten, O-Leerstellen mit unterschiedlicher Ladung und Verunreinigungen) geführt, die als aktive Zentren in OCM fungieren können. Insbesondere wurden morphologische Defekte und verschiedene Arten von F Zentren untersucht. Die Aktivierung von Methan an defekten MgO-Oberflächen wurde innerhalb eines Cluster-Ansatzes untersucht und durch periodische Berechnungen mittels periodic slab models verifiziert. Die Ergebnisse wurden mit vorhandenen experimentellen Daten verglichen.
This work presents a detailed quantum chemical (mostly DFT) study of H abstraction from methane by MgO and Li doped MgO. It is motivated by the UniCat effort to understand the oxidative coupling of methane (OCM). Based on the hypothesis that an Li+O•– species is responsible for the H abstraction step in OCM small cationic MgO and Li doped MgO clusters (which model O•– sites) were investigated. Because we were interested in real gas phase model systems the global minimum structures of (MgO)n+ and LiO(MgO)n-1 clusters were first determined (by means of genetic algorithm) and then used in subsequent reactivity studies. To check if there are any structural differences between neutral and cationic MgO clusters the neutral species were studied as well. After structure determination, the activation of methane by the O•– radical sites was investigated. The small cluster sizes enabled to study the reaction in detail and to compare different methods of calculations. The results were verified by comparison with more realistic models that mimic Li doped MgO surface, like non-embedded and embedded clusters and slab models. However, unexpected results for the Li+O•– sites led to the consideration of additional types of sites in MgO that may be active for OCM – such as low-coordinated O2- sites, O vacancies with different charge and impurity defects. In particular morphological defects and different types of F centers were investigated. Methane activation by defective MgO surface was studied by a cluster approach and then followed by periodic calculations on periodic slab models. The results were compared to existing experimental data.

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19

Langfeld, Kirsten [Verfasser], and Reinhard [Akademischer Betreuer] Schomäcker. "Impact of Synthesis Methods and Oxidizing Agents on the Catalytic Performance of Various Catalysts in the Oxidative Coupling of Methane / Kirsten Langfeld. Betreuer: Reinhard Schomäcker." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1021219967/34.

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20

Eckhardt, Björn [Verfasser], Ralph [Akademischer Betreuer] Krähnert, Peter [Akademischer Betreuer] Strasser, and Michael [Akademischer Betreuer] Wark. "Synthesis of micelle-templated metal oxides as catalysts for the oxidative coupling of methane / Björn Eckhardt. Gutachter: Peter Strasser ; Michael Wark ; Ralph Krähnert. Betreuer: Ralph Krähnert." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1066161658/34.

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21

Teixeira, Penteado Alberto [Verfasser], Jens-Uwe [Akademischer Betreuer] Repke, Jens-Uwe [Gutachter] Repke, and Flavio [Gutachter] Manenti. "Optimal design and evaluation of a biogas-based oxidative coupling of methane process / Alberto Teixeira Penteado ; Gutachter: Jens-Uwe Repke, Flavio Manenti ; Betreuer: Jens-Uwe Repke." Berlin : Technische Universität Berlin, 2021. http://d-nb.info/1238142699/34.

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22

Nghiem, Xuan Son [Verfasser], Günter [Akademischer Betreuer] Wozny, and Jens-Uwe [Akademischer Betreuer] Repke. "Ethylene production by oxidative coupling of Methane : new process fow diagram based on adsorptive separation / Xuan Son Nghiem. Gutachter: Günter Wozny ; Jens-Uwe Repke. Betreuer: Günter Wozny." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065669674/34.

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Esche, Erik [Verfasser], Günter [Akademischer Betreuer] Wozny, Ignacio E. [Akademischer Betreuer] Grossmann, and Jens-Uwe [Akademischer Betreuer] Repke. "MINLP optimization under uncertainty of a mini plant for the oxidative coupling of methane / Erik Esche. Betreuer: Günter Wozny. Gutachter: Günter Wozny ; Ignacio E. Grossmann ; Jens-Uwe Repke." Berlin : Technische Universität Berlin, 2015. http://d-nb.info/1078065098/34.

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Wang, Huan [Verfasser], Ralph [Akademischer Betreuer] Krähnert, Reinhard [Gutachter] Schomäcker, Thomas [Gutachter] Risse, and Ralph [Gutachter] Krähnert. "Property-performance correlations in the oxidative coupling of methane : the importance of carbonate formation and stability / Huan Wang ; Gutachter: Reinhard Schomäcker, Thomas Risse, Ralph Krähnert ; Betreuer: Ralph Krähnert." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1161461906/34.

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Schmack, Roman [Verfasser], Ralph [Akademischer Betreuer] Krähnert, Ralph [Gutachter] Krähnert, Reinhard [Gutachter] Schomäcker, and Evgenii [Gutachter] Kondratenko. "Property-performance relationships of catalysts in the oxidative coupling of methane : a combined statistical and experimental approach / Roman Schmack ; Gutachter: Ralph Krähnert, Reinhard Schomäcker, Evgenii Kondratenko ; Betreuer: Ralph Krähnert." Berlin : Technische Universität Berlin, 2017. http://d-nb.info/1156018005/34.

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Sadjadi, Setarehalsadat [Verfasser], Günter [Akademischer Betreuer] Wozny, Günter [Gutachter] Wozny, Reinhard [Gutachter] Schomäcker, and Annaland Martin van [Gutachter] Sint. "Analysis of fluidized-bed and fluidized-bed-membrane reactor concepts for oxidative coupling of methane / Setarehalsadat Sadjadi ; Gutachter: Günter Wozny, Reinhard Schomäcker, Martin van Sint Annaland ; Betreuer: Günter Wozny." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156184258/34.

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Colmenares, Maria [Verfasser], Aleksander [Akademischer Betreuer] Gurlo, Aleksander [Gutachter] Gurlo, Arne [Gutachter] Thomas, and Reyes [Gutachter] Mallada. "Ordered mesoporous silica COK-12: mesoscale tailoring, upscaling, continuous synthesis and application in the oxidative coupling of Methane / Maria Colmenares ; Gutachter: Aleksander Gurlo, Arne Thomas, Reyes Mallada ; Betreuer: Aleksander Gurlo." Berlin : Universitätsverlag der TU Berlin, 2018. http://d-nb.info/1162952644/34.

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Thum, Lukas [Verfasser], Reinhard [Akademischer Betreuer] Schomäcker, Reinhard [Gutachter] Schomäcker, Robert [Gutachter] Schlögl, and Evgenii [Gutachter] Kondratenko. "Transition metal-doped calcium oxide as model catalyst for the oxygen activation in the oxidative coupling of methane (OCM) reaction / Lukas Thum ; Gutachter: Reinhard Schomäcker, Robert Schlögl, Evgenii Kondratenko ; Betreuer: Reinhard Schomäcker." Berlin : Technische Universität Berlin, 2020. http://d-nb.info/1223981290/34.

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Yildiz, Mahmut [Verfasser], Reinhard [Akademischer Betreuer] Schomäcker, Arne [Akademischer Betreuer] Thomas, and Malte [Akademischer Betreuer] Behrens. "Influences of support material variation on structure and catalytic performance of MnxOy-Na2WO4/SiO2 catalyst for the oxidative coupling of methane / Mahmut Yildiz. Gutachter: Reinhard Schomäcker ; Arne Thomas ; Malte Behrens. Betreuer: Reinhard Schomäcker." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1066550301/34.

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Rochoux, Marie. "Matériaux conducteurs mixtes ioniques et électroniques pour le couplage oxydant du méthane." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10234/document.

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Le couplage oxydant du méthane (OCM) permet la transformation directe du méthane en éthylène (C2). A ce jour, le procédé catalytique n'atteint pas les critères requis de sélectivité et de rendement. La présence d'oxygène gazeux à haute température (T>700°C) favorise l'oxydation totale. L'utilisation d'un réacteur à membrane (RM) dense, composé de matériaux conducteurs ioniques et électroniques limite la présence de O2(g) dans le compartiment de réaction améliorant ainsi la sélectivité en C2. Cette thèse a pour cadre le développement de membranes catalytiques ayant un flux d'oxygène assez élevé pour atteindre une conversion supérieure à 25% et dont le revêtement catalytique entraine une sélectivité en C2 à 80%. Une méthode innovante, basée sur une approche microcinétique, a été développée pour déterminer le flux d'oxygène à travers les membranes à partir de mesures sur les poudres correspondantes (échange isotopique et ATG). Les constantes d'adsorption et de diffusion obtenues sont ensuite intégrées dans une équation de flux simulant la semi-perméabilité. Cette méthodologie, validée sur trois matériaux : Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), La0.6Sr0.4Co0.2Fe0.δ et Ba0.95La0.05FeO3-δ, permettra d'accélérer la découverte de nouveaux matériaux conducteurs d'oxygène. Les tests d'OCM ont été réalisés sur une membrane BSCF modifiée en surface par une couche mince catalytique. Deux catalyseurs ont été sélectionnés : Mn/NaWO4 très sélectif et LaSr/CaO très actif. Le rendement en réacteur membranaire est limité à 6%. Une analyse critique a été réalisée afin de concevoir une géométrie de réacteur membranaire optimale pour cette réaction
The oxidative coupling of methane (OCM) allowed the direct transformation of methane into ethylene (C2). Until now, the catalytic process does not reach the required criteria of selectivity and yield. The presence of gaseous oxygen at high temperature (T>700°C) favors the total oxidation. The use of a dense membrane reaction (MR), made of mixed ionic and electronic materials, limits the gaseous oxygen in the reaction compartment and thus improve the C2 selectivity. The goal of this PhD is to develop catalytic membranes exhibiting a flux high enough to reach a conversion higher than 25% and of which the catalytic coating leads to a C2 selectivity of 80%. An innovative method, based on a microkinetic approach, has been developed to determine the oxygen flux across a membrane from measurements on corresponding powders (isotopic exchange and TGA). The adsorption and diffusion constants obtained are then introduced in the flux equation simulating the semi-permeability. The methodology, validated on three materials: Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), La0.6Sr0.4Co0.2Fe0.δ et Ba0.95La0.05FeO3-δ, will allow to accelerate the discovery of new oxygen conducting. The OCM tests have been achieved on BSCF membrane modified by a thin layer of catalyst. Two catalysts have been selected: Mn/NaWO4 highly selective and LaSr/CaO highly active. The yield in membrane reactor cannot overstep 6%. A critical analysis has been achieved in order to design an optimal membrane reactor geometry for this reaction

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31

Kumarasamy, Puvaneswary. "Heterogeneous catalysis for methane oxidation." Thesis, Brunel University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326890.

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32

Vernon, Patrick D. F. "Heterogeneous catalytic oxidation reactions of methane." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308602.

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33

AlBanna, Muna. "Methane oxidation in landfill cover soil." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26834.

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Methane, one of the primary greenhouse gases, negatively affects climate change. Its atmospheric concentration has increased dramatically over the last century and is expected to continue rising due to human activities. Oxidation of methane by methanotrophic bacteria provides a sink for methane. The rate at which methane is biologically oxidized depends on different parameters. This study aims to better understand methane oxidation in landfill cover soils. This was done through laboratory batch reactor experiments, under two levels of moisture content, two soil layer thicknesses and with and without nutrient additions. Adding nutrients to the 200 mm layer of landfill cover soil that contained 30% moisture content (by weight), increased the CH4 oxidation efficiency from 38% to 81% and the CH4 substrate utilization from 2750 mumoles/L to 5540 mumoles/L. The kinetic constants were studied in the landfill cover soil. The maximum CH4 utilization rate for different experimental runs and under different levels of the three specified parameters were between 31 and 699 mumoles/dayxkg of dry soil weight. A statistical design model was developed to describe the expected methane oxidation efficiencies under different levels of moisture content and nutrient addition that can occur in a typical landfill cover soil.

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34

MacDonald, Jannette A. "Methane oxidation in temperate and tropical soils." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/11079.

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35

Williams, Gareth Richard. "Liquid phase catalytic partial oxidation of methane." Thesis, University of Bath, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760824.

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36

Mesarch, Scott Eugene. "A Computer Modelling Study of Methane Oxidation." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1134091533.

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37

Gueritey, Nicolas. "Valorisation chimique du méthane par oxydation catalytique sélective." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL034N.

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La conversion du méthane, principal constituant du gaz naturel, en produits valorisables et facilement transportables constitue un enjeu économique important. La réaction de couplage oxydant du méthane est une des voies les plus étudiées pour sa transformation directe en hydrocarbures supérieurs. Le rendement obtenu étant trop faible pour envisager une exploitation industrielle, il est nécessaire de mieux comprendre la réaction afin de pouvoir optimiser les paramètres physiques et cinétiques. Cette réaction est en effet complexe car elle comporte des réactions catalytiques et des réactions radicalaires en phase gazeuse. C'est pourquoi notre objectif était de progresser dans la connaissance du mécanisme par une étude expérimentale mettant en jeu trois réacteurs différents permettant de faire varier séparément les paramètres liés au catalyseur ou à la phase gazeuse. Nous avons par ailleurs fait une étude des phénomènes de diffusion intervenant dans ces réacteurs. La comparaison des résultats obtenus avec ces différents réacteurs a fourni des informations originales. Nous avons alors proposé un mécanisme susceptible de rendre compte de cette réaction, ce qui permet d'adapter les paramètres et le réacteur à la réaction et d'envisager une modélisation. Nous avons ainsi mis au point un réacteur capable de donner de bons rendements en couplage oxydant comme en gaz de synthèse

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38

Fathi, Marcus. "Catalytic partial oxidation of methane to synthetis gas." Doctoral thesis, Norwegian University of Science and Technology, Department of Chemical Engineering, 2000. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1831.

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39

Ye, Wei. "Catalytic oxidation of methane over supported palladium catalysts." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/MQ40128.pdf.

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40

Squire, Gavin Daniel. "Partial oxidation of methane to methanol and formaldehyde." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278072.

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41

Bradford, Mark Alexander. "The response of methane oxidation to environmental change." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286477.

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42

Jones, Hilary A. "The oxidation of methane in landfill soil cover." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306045.

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43

Baldwin, T. R. "Methane combustion over supported palladium catalysts." Thesis, University of Reading, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235041.

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44

Zhu, Jian N. "A feasibility study of methane reforming by partial oxidation." Curtin University of Technology, Department of Chemical Engineering, 2001. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12764.

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Utilisation of natural gas (mainly methane, CH[subscript]4), a clean and abundant resource, is of great importance. Conventional method, steam reforming, though still dominant, requires a considerately high capital investment and an intensive energy input. Reforming natural gas by partial oxidation, potentially one of the most attractive alternatives, has been investigated vigorously for decades, mainly focusing on looking for suitable catalyst and understanding of the mechanisms of methane partial oxidation. This work focuses on the feasibility of methane partial oxidation reforming from gas phase reaction under fuel-rich conditions.Firstly, a detailed thermodynamic analysis has been conducted, which covers a broad range of operation conditions of temperature up to 2073 K, pressure up to 100 atm and initial O(subscript)2/CH(subscript)4 ratio of 0 to 2.5. It has been found that high syn-gas (H(subscript)2 and CO) yields can be achieved when the temperature is above 1073 K and the initial O(subscript)2/CH(subscript)4 ratio close to 0.5. High pressure is not favoured. However, high temperatures can suppress the effect of high pressures.Carbon deposition, a crucially important factor in methane partial oxidation, is mainly examined by means of thermodynamic analysis. Solid carbon was identified the major carbon deposition form, which could severely happen if the initial O(subscript)2/CH(subscript)4 ratio is less than 0.5. This feature was also indirectly proven during the experimental tests.Secondly, a series of CHEMKIN simulations were performed using various CH(subscript)4 oxidation reaction mechanisms. The general trend of the CH(subscript)4 partial oxidation reforming was revealed by simulations using the GRI, NIST and Konnov mechanisms. A new concept characterising CH(subscript)4 partial oxidation was conceived. i.e., a fast oxidation zone and a slow conversion ++
zone, the reaction is under chemical control that requests high operating temperatures, and the reaction can be accelerated by using relatively high initial 0(subscript)2/CH(subscript)4 ratios.Experimental tests were performed to verify the findings obtained in thermodynamic and kinetic studies, and to identify appropriate reaction schemes for further analysis. Prediction from the NIST mechanisms has shown to be in good agreement with experimental observation when the temperature is less than 1273 K. For higher temperatures the NIST under-predicts the H(subscript)2 yield caused by the lack of carbon formation mechanisms. Two other mechanisms (Konnov and GRI) predicted similar trends but the reaction predicted commenced earlier. Therefore, the NIST was identified to be the best.NO(subscript)x catalytic effect on CH4 oxidation at fuel-rich conditions was confirmed experimentally. However, this effect only exists where the oxygen is available. Therefore, employing NO(subscript)x cannot help the CH(subscript)4 partial oxidation in the second reaction zone. Solely relying on NO(subscript)x to speed up the process or lower the operating temperature is not possible. However, employing NO(subscript)x to initiate the reaction at lower temperatures is viable. The possibility of taking the advantage of NOx catalytic effect for direct synthesis of CH3OH (methanol) has been shown feasible and, more attractively, the operating temperatures required are much lower than that for syn-gas production.Among three reaction schemes, i.e., the Glarborg, Bromly and Dagaut, which are able to account for the NO(subscript)x catalytic effect, the Glarborg mechanism proved to be the best in reproducing experimental measurements for syn-gas production tests. However, none available mechanisms can predict similar magnitude of the direct synthesis of CH(subscript)3OH. To understand the mechanisms ++
of NO(subscript)x catalytic effect, a reaction scheme, Partial Oxidation Mechanisms (POM), has been composed successfully adding five additional reactions into the NIST. The POM can reveal the major catalytic reaction pathways and it is suitable for CH(subscript)4 partial oxidations both with and without NO(subscript)x addition.Finally, a series of simulations were conducted to conservatively estimate the feasibility of CH(subscript)4 partial oxidation using POM. High syn-gas yield is achievable within a reasonable residence time using adiabatic reactor. The variables significantly affecting the syn-gas yield, are preheating temperature, operating pressure, inert dilution, initial ratio of O(subscript)2/CH(subscript)4 and residence time. If NO(subscript)x is used as a catalyst, the preheating temperature can be further reduced.

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45

Zhu, Jian Ning. "A feasibility study of methane reforming by partial oxidation /." Full text available, 2001. http://adt.curtin.edu.au/theses/available/adt-WCU20030526.143807.

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46

Fan, Lichao [Verfasser]. "Anaerobic oxidation of methane in paddy soil / Lichao Fan." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1221802380/34.

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47

Jones, Peter Neil. "The elementary reactions involved in the oxidation of methane." Thesis, University of Hull, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294074.

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48

Gilbert, Phillip James. "Molybdena-based catalysts for the partial oxidation of methane." Thesis, University of Hull, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335154.

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49

Starr, Sean Michael. "Microbial methane oxidation in the marine and estuarine environment." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313378.

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50

Gopalkrishna, Akshoy. "Catalytic Oxidation of Methane using Single Crystal Silicon Carbide." [Tampa, Fla. : s.n.], 2003. http://purl.fcla.edu/fcla/etd/SFE0000105.

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