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Artigos de revistas sobre o assunto "CO2 reduction catalysis"

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Dagorne, Samuel. "Recent Developments on N-Heterocyclic Carbene Supported Zinc Complexes: Synthesis and Use in Catalysis". Synthesis 50, n.º 18 (28 de junho de 2018): 3662–70. http://dx.doi.org/10.1055/s-0037-1610088.

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The present contribution reviews the synthesis, reactivity, and use in catalysis of NHC–Zn complexes reported since 2013. NHC-stabilized Zn(II) species typically display enhanced stability relative to common organozinc species (such as Zn dialkyls), a feature of interest for the mediation of various chemical processes and the stabilization of reactive Zn-based species. Their use in catalysis is essentially dominated by reduction reactions of various unsaturated small molecules (including CO2), thus primarily involving Zn–H and Zn–alkyl derivatives as catalysts. Simple NHC adducts of Zn(II) dihalides also appear as effective catalysts for the reduction amination of CO2 and borylation of alkyl/aryl halides. Stable and well-defined Zn alkoxides have also been prepared and behave as effective catalysts in the polymerization of cyclic esters/carbonates for the production of well-defined biodegradable materials. Overall, the attractive features of NHC-based Zn(II) species include ready access, a reasonable stability/reactivity balance, and steric/electronic tunability (through the NHC source), which should promote their further development.1 Introduction2 NHC-Supported Zinc Alkyl/Aryl Species2.1 Synthesis2.2 Reactivity and Use in Catalysis3 NHC-Supported Zinc Hydride Species3.1 Synthesis3.2 Reactivity and Use in Catalysis4 NHC-Supported Zinc Amido/Alkoxide Species4.1 Synthesis4.2 Use in Catalysis5 NHC-Supported Zinc Dihalide Species5.1 Synthesis5.2 Use in Catalysis6 Other NHC-Stabilized Zn Species7 Conclusion
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Tian, Jindan, Ru Han, Qiangsheng Guo, Zhe Zhao e Na Sha. "Direct Conversion of CO2 into Hydrocarbon Solar Fuels by a Synergistic Photothermal Catalysis". Catalysts 12, n.º 6 (2 de junho de 2022): 612. http://dx.doi.org/10.3390/catal12060612.

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Photothermal coupling catalysis technology has been widely studied in recent years and may be a promising method for CO2 reduction. Photothermal coupling catalysis can improve chemical reaction rates and realize the controllability of reaction pathways and products, even in a relatively moderate reaction condition. It has inestimable value in the current energy and global environmental crisis. This review describes the application of photothermal catalysis in CO2 reduction from different aspects. Firstly, the definition and advantages of photothermal catalysis are briefly described. Then, different photothermal catalytic reductions of CO2 products and catalysts are introduced. Finally, several strategies to improve the activity of photothermal catalytic reduction of CO2 are described and we present our views on the future development and challenges of photothermal coupling. Ultimately, the purpose of this review is to bring more researchers’ attention to this promising technology and promote this technology in solar fuels and chemicals production, to realize the value of the technology and provide a better path for its development.
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Srivastava, Sumit, Manvender S. Dagur, Afsar Ali e Rajeev Gupta. "Trinuclear {Co2+–M3+–Co2+} complexes catalyze reduction of nitro compounds". Dalton Transactions 44, n.º 40 (2015): 17453–61. http://dx.doi.org/10.1039/c5dt03442f.

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Trinuclear {Co2+–Co3+–Co2+} and {Co2+–Fe3+–Co2+} complexes function as reusable heterogeneous catalysts for the selective reduction of assorted nitro compounds to their corresponding amines. The mechanistic investigations suggest the involvement of a Co(ii)–Co(i) cycle in the catalysis.
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Lisovski, Oleg, Sergei Piskunov, Dmitry Bocharov, Yuri Zhukovskii, Janis Kleperis, Ainars Knoks e Peteris Lesnicenoks. "CO2 and CH2 Adsorption on Copper-Decorated Graphene: Predictions from First Principle Calculations". Crystals 12, n.º 2 (28 de janeiro de 2022): 194. http://dx.doi.org/10.3390/cryst12020194.

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Single-layer graphene decorated with monodisperse copper nanoparticles can support the size and mass-dependent catalysis of the selective electrochemical reduction of CO2 to ethylene (C2H4). In this study, various active adsorption sites of nanostructured Cu-decorated graphene have been calculated by using density functional theory to provide insight into its catalytic activity toward carbon dioxide electroreduction. Based on the results of our calculations, an enhanced adsorption of the CO2 molecule and CH2 counterpart placed atop of Cu-decorated graphene compared to adsorption at pristine Cu metal surfaces was predicted. This approach explains experimental observations for carbon-based catalysts that were found to be promising for the two-electron reduction reaction of CO2 to CO and, further, to ethylene. Active adsorption sites that lead to a better catalytic activity of Cu-decorated graphene, with respect to general copper catalysts, were identified. The atomic configuration of the most selective CO2 toward the reduction reaction nanostructured catalyst is suggested.
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Petersen, Haley A., Tessa H. T. Myren e Oana R. Luca. "Redox-Active Manganese Pincers for Electrocatalytic CO2 Reduction". Inorganics 8, n.º 11 (11 de novembro de 2020): 62. http://dx.doi.org/10.3390/inorganics8110062.

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The decrease of total amount of atmospheric CO2 is an important societal challenge in which CO2 reduction has an important role to play. Electrocatalytic CO2 reduction with homogeneous catalysts is based on highly tunable catalyst design and exploits an abundant C1 source to make valuable products such as fuels and fuel precursors. These methods can also take advantage of renewable electricity as a green reductant. Mn-based catalysts offer these benefits while incorporating a relatively cheap and abundant first-row transition metal. Historically, interest in this field started with Mn(bpy-R)(CO)3X, whose performance matched that of its Re counterparts while achieving substantially lower overpotentials. This review examines an emerging class of homogeneous Mn-based electrocatalysts for CO2 reduction, Mn complexes with meridional tridentate coordination also known as Mn pincers, most of which contain redox-active ligands that enable multi-electron catalysis. Although there are relatively few examples in the literature thus far, these catalysts bring forth new catalytic mechanisms not observed for the well-established Mn(bpy-R)(CO)3X catalysts, and show promising reactivity for future studies.
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Hahn, Christopher. "(Invited) Steering Electrocatalytic CO2 Reduction Reactivity Using Microenvironments". ECS Meeting Abstracts MA2022-02, n.º 49 (9 de outubro de 2022): 1879. http://dx.doi.org/10.1149/ma2022-02491879mtgabs.

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A key challenge in electrocatalysis is co-designing the catalyst and its microenvironment to work in concert to efficiently steer complex reaction networks. First, I will describe the development of a tandem catalysis strategy on Au/Cu electrocatalysts to control the potential energy landscape of the CO2 and CO reduction at length scales beyond the active site and achieve synergistic catalytic activity for alcohols superior to that of either Cu or Au. Next, I will provide examples of CO2 reduction on catalysts supported on gas diffusion electrodes to discuss how the intrinsic catalysis and mass transport are interconnected through microenvironments, leading to emergent catalytic properties under industrially relevant reaction rates. Finally, I will conclude by providing our perspective on key remaining challenges to the scale-up of CO2 electrolyzers within the context of electrifying the chemicals manufacturing sector.
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Cao, Yanwei, Qiongyao Chen, Chaoren Shen e Lin He. "Polyoxometalate-Based Catalysts for CO2 Conversion". Molecules 24, n.º 11 (30 de maio de 2019): 2069. http://dx.doi.org/10.3390/molecules24112069.

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Polyoxometalates (POMs) are a diverse class of anionic metal-oxo clusters with intriguing chemical and physical properties. Owing to unrivaled versatility and structural variation, POMs have been extensively utilized for catalysis for a plethora of reactions. In this focused review, the applications of POMs as promising catalysts or co-catalysts for CO2 conversion, including CO2 photo/electro reduction and CO2 as a carbonyl source for the carbonylation process are summarized. A brief perspective on the potentiality in this field is proposed.
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Zhou, Yiying, Junxi Cai, Yuming Sun, Shuhan Jia, Zhonghuan Liu, Xu Tang, Bo Hu, Yue Zhang, Yan Yan e Zhi Zhu. "Research on Cu-Site Modification of g-C3N4/CeO2-like Z-Scheme Heterojunction for Enhancing CO2 Reduction and Mechanism Insight". Catalysts 14, n.º 8 (20 de agosto de 2024): 546. http://dx.doi.org/10.3390/catal14080546.

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In this work, the successful synthesis of a Cu@g-C3N4/CeO2-like Z-scheme heterojunction through hydrothermal and photo-deposition methods represents high CO2 reduction activity with remarkable CO selectivity, as evidenced by the impressive CO yield of 33.8 μmol/g for Cu@g-C3N4/CeO2, which is over 10 times higher than that of g-C3N4 and CeO2 individually. The characterization and control experimental results indicate that the formation of heterojunctions and the introduction of Cu sites promote charge separation and the transfer of hot electrons, as well as the photothermal effect, which are the essential reasons for the improved CO2 reduction activity. Remarkably, Cu@g-C3N4/CeO2 still exhibits about 92% performance even after multiple cycles. In situ FTIR was utilized to confirm the production of COOH* at 1472 cm−1 and to elucidate the mechanism behind the high selectivity for CO production. The study’s investigation into the wide-ranging applicability of the Cu@g-C3N4/CeO2-like Z-scheme heterojunction catalysts is noteworthy, and the exploration of potential reaction mechanisms for CO2 reduction adds valuable insights to the field of catalysis.
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Xue, Sensen, Xingyou Liang, Qing Zhang, Xuefeng Ren, Liguo Gao, Tingli Ma e Anmin Liu. "Density Functional Theory Study of CuAg Bimetal Electrocatalyst for CO2RR to Produce CH3OH". Catalysts 14, n.º 1 (20 de dezembro de 2023): 7. http://dx.doi.org/10.3390/catal14010007.

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Converting superfluous CO2 into value-added chemicals is regarded as a practical approach for alleviating the global warming problem. Powered by renewable electricity, CO2 reduction reactions (CO2RR) have attracted intense interest owing to their favorable efficiency. Metal catalysts exhibit high catalytic efficiency for CO2 reduction. However, the reaction mechanisms have yet to be investigated. In this study, CO2RR to CH3OH catalyzed by CuAg bimetal is theoretically investigated. The configurations and stability of the catalysts and the reaction pathway are studied. The results unveil the mechanisms of the catalysis process and prove the feasibility of CuAg clusters as efficient CO2RR catalysts, serving as guidance for further experimental exploration. This study provides guidance and a reference for future work in the design of mixed-metal catalysts with high CO2RR performance.
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Hall, Anthony Shoji, Youngmin Yoon, Anna Wuttig e Yogesh Surendranath. "Mesostructure-Induced Selectivity in CO2 Reduction Catalysis". Journal of the American Chemical Society 137, n.º 47 (18 de novembro de 2015): 14834–37. http://dx.doi.org/10.1021/jacs.5b08259.

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Teses / dissertações sobre o assunto "CO2 reduction catalysis"

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Smith, Adrien. "Activation and reduction of CO2 by metalloporphyrin-based molecular catalysts". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASF039.

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La transformation du CO₂ en formes réduites valorisables du carbone constitue une approche vers le recyclage de ce gaz à effet de serre, en réintroduisant dans le cycle du carbone des synthons C1 qui ne sont pas issus de ressources fossiles. Les tétraphénylporphyrines de fer et leurs dérivés se sont révélés être des catalyseurs moléculaires efficaces et sélectifs pour la réduction du CO₂ en CO. L'introduction de différentes fonctions dans la seconde sphère de coordination des porphyrines a aussi permis d'améliorer la surtension et les taux catalytiques.Inspirés par la poche distale des centres actifs des enzymes, une porphyrine de fer avec une anse portant une fonction carboxylate est étudiée. Les investigations électrochimiques, cinétiques, et de chimie computationnelle montrent que ce catalyseur permet de réduire fortement la surtension nécessaire à la catalyse tout en conservant des taux catalytiques très élevés. Il est proposé que la fonction carboxylate, initialement ligand axial du métal, joue en conditions catalytiques le rôle important dans l'insertion et la transformation du CO₂.Ensuite, deux porphyrines de fer ont été synthétisées avec un imidazolium à différentes positions par rapport au centre métallique. L'objectif premier était d'établir une corrélation entre la distance de la fonction cationique et les propriétés du catalyseur, afin de guider la conception de nouveaux catalyseurs plus performants.Cependant, l'étude électrochimique de ces composés révèle que ces groupements imidazolium peuvent être électroactifs. La résonance paramagnétique électronique a été utilisée afin de décrire leurs différentes formes réduites. Ces travaux ont amené à dévoiler la nature électroactive de ces groupements imidazolium portés par ces nouvelles porphyrines de fer
Transforming CO₂ into valuable reduced forms of carbon is an interesting approach towards the recycling of this greenhouse gas, by introducing non-fossil fuel based C1 building blocks back into the carbon cycle. Tetraphenyl iron porphyrins and derivatives have been shown to be efficient and selective molecular catalysts for CO₂ reduction to CO. The introduction of various functions in the second coordination sphere of porphyrins showed great improvements of both the overpotential and the catalytic rates.Inspired by the distal pocket of enzymatic active centers, an iron porphyrin with a carboxylate strap is investigated. Electrochemical, kinetic and computational chemistry studies show that this catalyst operates at a low overpotential, while maintaining high catalytic rates. It is proposed that the carboxylate function, initially acting as an axial ligand of the metal, plays an important role in the insertion and transformation of CO₂, in synergy with a water molecule trapped in the superstructure.Furthermore, two iron porphyrins were synthetized bearing an imidazolium group at various positions with respect to the metal center. The original goal of this study was to establish a correlation between the distance of the cationic group from the metal center and the catalytic performances of the catalyst, which can guide the design of new catalysts for CO₂ reduction.The electrochemical study of these catalysts revealed that these imidazolium functions can be electroactive. Electron paramagnetic resonance was used to describe their various reduced forms. These studies revealed and describe the potential electroactive behavior of the imidazolium groups on these novel iron porphyrins catalysts
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Afonso, Joana da Costa Franco. "Catalytic hydrogenation of carbon dioxide to form methanol and methane". Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10854.

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Woolerton, Thomas William. "Development of enzymatic H2 production and CO2 reduction systems". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:393741ac-94b1-4d56-b680-d9a434db77e2.

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One of today’s most pressing scientific challenges is the conception, development and deployment of renewable energy technologies that will meet the demands of a rapidly increasing population. The motivation is not only dwindling fossil fuel reserves, but also the necessary curtailment of emissions of the greenhouse gas carbon dioxide (a product of burning fossil fuels). The sun provides a vast amount of energy (120,000 TW globally), and one major challenge is the conversion of a fraction of this energy into chemical energy, thereby allowing it to be stored. Dihydrogen (H₂) that is produced from water is an attractive candidate to store solar energy (a ‘solar fuel’), as are high energy carbon-containing molecules (such as CO) that are formed directly from carbon dioxide. One key aspect is the development of catalysts that are able to offer high rates and efficiencies. In biology, some microbes acquire energy from the metabolism of H₂ and CO. The biological catalysts - enzymes - that are responsible are hydrogenases (for the oxidation of H₂ to protons); and carbon monoxide dehydrogenases (CODHs, for the oxidation of CO to CO₂). These redox enzymes, containing nickel and iron as the only metals, are extraordinary in terms of their catalytic characteristics: many are fully reversible catalysts and offer very high turnover frequencies (thousands per second are common), with only tiny energy input requirements. This Thesis uses a hydrogenase from the bacterium Escherichia coli, and two CODHs from the bacterium Carboxydothermus hydrogenoformans, as the catalysts in H2 production and CO₂ reduction systems. Chapter 3 describes the concept and development not of a solar fuel system, but of a device that catalyses the water-gas shift reaction (the reaction between CO and water to form H₂ and CO₂) - a process of major industrial importance for the production of high purity H₂. Chapters 4, 5 and 6 detail photochemical CO₂ reduction systems that are driven by visible light. These systems, operating under mild, aqueous conditions, involve CODHs attached either to TiO₂ nanoparticles that are sensitised to visible light by the co-attachment of a ruthenium-based dye complex, or to cadmium sulfide nanomaterials that, having a narrow band gap, are inherently photoexcitable by visible light. The motivation here is not the construction of technological devices; indeed, the enzymes that are used are fragile, highly sensitive to oxygen, and impossible to scale to industrial levels. Rather, the drivers are those of scientific curiosity (can the incorporation of these remarkable biological catalysts enable the creation of outstanding solar fuel devices?), and of producing systems that serve as benchmarks and inspiration for the development of fully synthetic systems that are robust and scalable.
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Pršlja, Paulina. "Theoretical Studies of Single-Site Catalysts for Efficient Electrochemical CO2 Reduction". Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/671468.

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El desenvolupament de l’electroquímica té el potenciar d’utilizar el CO2 com a matèria primera per a la producció sostenible de compostos i materials i té un gran impacte en la indústria química. El catalitzador “de lloc únic” (single site catalyst) és un material prometedor per aconseguir elevades activitats y selectivitats cap a la formació de CO i hidrocarburs C1. L’estructura única d’aquest catalitzador derivat de carboni redueix la competència d’aquests processos amb d’altres processos catalítics com la hydrogen evolution reaction (HER) perquè el single site catalyst requereix la unió de l’hidrogen a la part superior. En aquesta tesi s’han aplicat mètodes DFT i conceptes electroquímics per tal d’entendre els processos de reducció de CO2. Al tercer capítol es descriu la importància de les característiques estructurals del single site catalyst, juntament amb els conceptes relacionats amb la química de coordinació necessaris per a entendre l’activitat del catalitzador en la reacció electroquímica de reducció del CO2 (eCO2RR). L’objectiu del capítol 4 és establir correlacions experimentals i teòriques entre les propietats fisicoquímiques i catalítiques de la eCO2RR que dona com a producte CO per al catalitzador del MNC. El procés de reconstrucció de les nanopartícules de Ni mitjançant la desintegració de Ni(CO)2 en materials de carboni dopats amb N es descriu al capítol 5. Per últim, en el capítol 6 es descriu la selectivitat dels productes de reducció de CO2 tenint en compte com afecta el potencial i la temperatura sobre el catalitzador modelat de CoTPP/MWCNT.
El desarrollo de la electroquímica tiene el potencial de utilizar el CO2 como materia prima para la producción sostenible de compuestos y materiales y tiene un gran impacto en la industria química. El catalizador “de sitio único” (single site catalyst) es un material prometedor para lograr una elevada actividad y selectividad hacia CO e hidrocarburos C1. La estructura única de este catalizador derivado de carbono reduce la competencia de estos procesos con otros procesos catalíticos como la reacción hydrogen evolution reaction (HER) porque el single site catalyst requiere la unión de hidrógeno en la parte superior. En esta tesis, métodos DFT y conceptos electroquímicos computacionales han sido aplicados para entender los procesos de reducción de CO2. En el capítulo 3 se describe la importancia de las características estructurales del single site catalyst, además de los conceptos relacionados con la química de coordinación que se aplican para comprender la actividad del catalizador en la reacción electroquímica de reducción de CO2 (eCO2RR). El objetivo del capítulo 4 es establecer correlaciones experimentales y teóricas entre las propiedades fisicoquímicas y catalíticas para la eCO2RR hacia CO para el catalizador del MNC. El proceso de reconstrucción de las nanopartículas de Ni mediante la desintegración de Ni(CO)2 en materiales de carbono dopados con N se describe en el capítulo 5. Por último, en el capítulo 6 se describe la selectividad de los productos de reducción de CO2 teniendo en cuenta cómo afecta el potencial y la temperatura sobre el catalizador modelado de CoTPP/MWCNT.
The development of electrochemistry has the potential to use CO2 as a feedstock for the sustainable production of chemicals and materials and it has an important impact on the chemical industry. Single site catalyst is a promising new material for achieving high activity and selectivity towards CO and C1 hydrocarbons. The unique structure of carbon-based catalyst makes it a good compressor of competing Hydrogen evolution reaction (HER) because the single site requires an ontop binding of hydrogen. In this thesis, I applied DFT methods and computational electrochemical concepts for understanding the processes of CO2 reduction (eCO2RR). In chapter 3 I described the importance of single-site structural features catalyst, besides the basic concept of the coordination chemistry that is applied to understand eCO2RR activity of the catalyst. The aim of chapter 4 was to establish experimental and theoretical correlations between physicochemical and catalytic properties for the eCO2RR towards CO for MNC catalyst. The process of reconstruction of Ni nanoparticles by the disintegration of Ni(CO)2 on N-doped carbon materials is described in chapter 5. Finally, in chapter 6 I unraveled the selectivity of CO2 reduction products that were influenced by potential and the temperature over modeled CoTPP/MWCNT catalyst.
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Dattila, Federico. "Modelling and mapping pathways of electrochemical CO2 reduction on modified catalytic surfaces". Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/670954.

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La reducció de CO2 és l'únic procés per generar combustibles verds amb un impacte negatiu net en les emissions de CO2. Per tant, el desenvolupament futur de la nostra societat necessita una aplicació industrial d'aquesta tecnologia per produir productes químics d'ús intensiu com l'etilè. El coure és un material únic per catalitzar aquests productes, però, avenços significatius en aquest procés requereixen una comprensió teòrica profunda de la seva complexitat. En aquesta tesi em vaig proposar desenvolupar mètodes teòrics per abordar els principals factors involucrats en la reducció de CO2 amb coure: (i) reconstrucció superficial a causa de potencial negatiu; (ii) efectes químics sobre la selectivitat; i (iii) l'efecte de l'electròlit. Els capítols I i II es van dedicar a les motivacions i mètodes i el Capítol 3 a comprovar resultats experimentals ben establerts. En el capítol 4 vaig investigar la reconstrucció del coure policristal·lí a potencials negatius. Aquest procés està impulsat per la polarització de la superfície, que promou dominis (100) i defectes. Seguint les previsions teòriques, vaig sintetitzar un catalitzador a base de coure eficaç per produir etilè amb alt rendiment. En el capítol V, vaig estudiar l'òxid de coure per investigar l'estat d'oxidació del coure, la seva coordinació i els llocs superficials actius cap a la producció de químics C2+. Entre els resultats, vaig demostrar que la polarització impulsa la reducció de CO2, mentre un nou intermedi, el glioxilato desprotonado, millora la selectivitat fins als C2+. En el capítol VI em vaig dedicar a efectes químics que influencien la reactivitat el coure. Adatomos de sofre, que actuen com a centres d'ancoratge, permeten la generació de formiat. Finalment, a l'apèndix A vaig introduir l'efecte dels cations sobre la reducció de CO2, que encara no es comprèn completament, però té una clara rellevància en la distribució del producte.
La reducción de CO2 es el único proceso para generar combustibles verdes con un impacto negativo neto en las emisiones de CO2. Por lo tanto, el desarrollo futuro de nuestra sociedad necesita una aplicación industrial de esta tecnología para producir productos químicos de uso intensivo como el etileno. El cobre es un material único para catalizar estos productos, sin embargo, avances significativos en este proceso requieren una comprensión teórica profunda de su complejidad. En esta tesis me propuse desarrollar métodos teóricos para abordar los principales factores involucrados en la reducción de CO2 con cobre: (i) reconstrucción superficial debido a potencial negativo; (ii) efectos químicos sobre la selectividad; y (iii) el efecto del electrolito. Los capítulos I y II se dedicaron a las motivaciones y métodos y el Capítulo 3 a comprobar resultados experimentales bien establecidos. En el capítulo 4 investigué la reconstrucción del cobre policristalino a potenciales negativos. Este proceso está impulsado por la polarización de la superficie, que promueve dominios (100) y defectos. Siguiendo las previsiones teóricas, sinteticé un catalizador a base de cobre eficaz para producir etileno con alto rendimiento. En el Capítulo V, estudié el óxido de cobre para investigar el estado de oxidación del cobre, su coordinación y los sitios superficiales activos hacia la producción de químicos C2+. Entre los resultados, demostré que la polarización impulsa la reducción de CO2, mientras un nuevo intermedio, el glioxilato desprotonado, mejora la selectividad hasta los C2+. En el capítulo VI me dediqué a efectos químicos que influencian la reactividad del cobre. Adatomos de azufre, que actúan como centros de anclaje, permiten la generación de formiato. Finalmente, en el Apéndice A introduje el efecto de los cationes sobre la reducción de CO2, que aún no se comprende completamente, pero tiene una clara relevancia en la distribución del producto.
CO2 reduction is the only process which can generate green fuels with a net negative impact in CO2 emissions. Therefore, the future development of our society needs an industrial scale up of this technology, involving the production of heavily used chemicals such as ethylene. Copper is a unique material for catalyzing these C2+ products, however significant advances need a deep theoretical understanding of the complexity of this material under CO2 reduction conditions. In this thesis I aimed at developing theoretical methods to address the main factors involved in this process: (i) surface reconstruction at negative potential; (ii) chemical effects on copper selectivity; and (iii) the effect of the electrolyte. Chapters I and II were dedicated to the motivations and methods. After having benchmarked in Chapter 3 well-established experimental results, such as the morphology dependence of CO2 product distribution on copper local morphology, I investigated the reconstruction of polycrystalline copper at negative potentials. This process is driven by local surface polarization, which destabilizes close-packed domains and promotes (100) facets and defects. Following theoretical guidelines, I synthesized an effective copper-based catalyst with produced ethylene at high yield and high current density. In Chapter V I studied a complex oxide-derived copper material to provide insights about copper oxidation state, its coordination and surface ensembles active toward C2+ chemicals. Among the outcomes, I demonstrated that polarization drives CO2 reduction activity, whilst a newly reported intermediate, a deprotonated glyoxylate, triggers C2+ selectivity. In chapter VI I dedicated to chemical effects on copper reactivity. Sulfur adatoms, acting as strong tethering centers enable the generation of formate, a chemical employed as preservative for animal food stock. Finally, in Appendix A I introduced cation effect on CO2 reduction, not yet fully understood but having a clear relevance on product distribution.
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Fugate, Elizabeth Anne. "Investigation of Electronic Structure Effects of Transition Metal Oxides toward Water Oxidation and CO2 Reduction Catalysis". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462868623.

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Chakraborty, Sumit. "Homogeneous Catalysis of Nickel Hydride Complexes Bearing a Bis(phosphinite) Pincer Ligand". University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342716471.

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Frogneux, Xavier. "Transformations réductrices du CO2 pour la formation de liaisons C-N et C-C". Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112136/document.

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Dans le monde actuel, le dioxyde de carbone (CO2) est le déchet majoritaire issu de l’utilisation des ressources fossiles mais il est encore peu utilisé dans les applications à grande échelle. Afin de tirer parti de son abondance, le développement de nouvelles transformations chimiques du CO2 pour accéder à des produits de chimie fine connait un intérêt croissant au sein de la communauté scientifique. Tout particulièrement, la formation de liaison(s) C-N à partir du CO2 et d’un substrat azotés permet d’accéder à des produits à hautes valeurs énergétiques et commerciales. Un second type de transformation désirable est la formation de liaison C-C à partir du CO2 afin de synthétiser des dérivés d’acides carboxyliques comme des esters. L’utilisation d’hydrosilanes, réducteurs doux, permet de travailler sous 1 bar de CO2 avec des catalyseurs à base de métaux peu coûteux et abondants tels que le fer et le zinc ou bien avec des organocatalyseurs. Les synthèses de formamides, de méthylamines ou d’aminals à partir du CO2 ont ainsi été développées par hydrosilylation. Enfin, la carboxylation des carbosilanes à partir du CO2 a été développée pour la première fois avec un catalyseur à base de cuivre. Dans le cas des 2-pyridylsilanes, l’utilisation de sels de fluorures pentavalents permet d’activer le substrat efficacement sans catalyseur
In the current world, carbon dioxide (CO2) is the major waste of the massive utilization of fossil resources but only few applications have been developed using this compound. In order to take advantage of its abundancy, the development of novel chemical transformation of CO2 to produce fine chemicals is of high interest in the scientific community. In particular, the formation of C-N bond(s) from CO2 and amine compounds unlocks a new way to access high energy and value-added. A second type of highly desirable transformation is the formation of C-C bonds with CO2 so as to synthesize carboxylic acid derivatives. The utilization of hydrosilanes as mild reductants allows the reactions to proceed under 1 bar of CO2 with abundant and cheap metal-based catalysts (iron, zinc) or with organocatalysts. The synthesis of formamides, methylamines and aminals from CO2 are described herein. Ultimately, the catalytic carboxylation of carbosilanes has been achieved for the first time using copper-based complexes. In the specific case of 2-pyridylsilanes, the use of pentavalent fluoride salts allowed us to perform the reaction without catalyst
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Giang, Hannah. "Rational Fabrication of Molybdenum Disulfide and Metal-doped Molybdenum Disulfide Thin Films via Electrodeposition Method for Energy Storage, Catalysis, and Biosensor Applications". OpenSIUC, 2020. https://opensiuc.lib.siu.edu/dissertations/1861.

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This dissertation presents studies electrodeposited MoS2 and metal-doped MoS2 thin films, and their performance for energy storage, catalysis, and biosensor applications. Ni-doped MoS2 thin films were fabricated by electrodeposition from electrolytes containing both MoS42- and varying concentrations of Ni2+, followed by annealing at 400 ºC for 2 h in an Ar atmosphere. The film resistivity increased from 11.3 µΩ-cm for un-doped MoS2 to 32.8 µΩ-cm for Ni-doped MoS2 containing 9 atom% Ni. For all Ni dopant levels studied, only the x-ray diffraction (XRD) pattern expected for MoS2 is observed, with the average grain size increases with increasing Ni content. Ni-doped MoS2 thin films were tested for their activity towards the hydrogen evolution reaction (HER) in 0.5M H2SO4. Tafel equation fits reveal that the catalytic activity for HER, as measured by the exchange current density, increases up to 6 atom% Ni, and then decreases slightly for 9 atom% Ni. Ni-doped MoS2 thin films were also tested in 1.0 M Na2SO4 for use within electrochemical supercapacitors, and the capacitance per unit area increases by 2-3x for 9 atom% Ni-doped MoS2 relative to un-doped MoS2. The highest specific capacitance obtained for Ni-doped MoS2 during galvanostatic charge-discharge measurements is ~300 F/g
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Kour, Gurpreet. "First principles investigations on transition metal based electrocatalysts for efficient clean energy conversion". Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/232798/1/Gurpreet_Kour_Thesis.pdf.

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This dissertation relates to the application of density functional theory to the design of novel nanoelectrocatalysts for various electrochemical reduction reactions such as carbon dioxide reduction reactions, carbon monoxide reduction reactions and nitrogen reduction reactions. Many electrocatalysts with high activity, excellent selectivity and stability were designed and engineered using first principle calculations. These findings could potentially guide the experimentalists for creating clean and sustainable energy resources.
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Livros sobre o assunto "CO2 reduction catalysis"

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Weichselbaumer, Melanie. Pyridine-functionalized Polymeric Catalysts for CO2-Reduction. Wiesbaden: Springer Fachmedien Wiesbaden, 2015. http://dx.doi.org/10.1007/978-3-658-10358-3.

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Weichselbaumer, Melanie. Pyridine-functionalized Polymeric Catalysts for CO2-Reduction. Springer Spektrum, 2015.

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Weichselbaumer, Melanie. Pyridine-Functionalized Polymeric Catalysts for CO2-Reduction. Spektrum Akademischer Verlag GmbH, 2015.

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4

Ishida, Hitoshi, Charles Machan, Marc Robert e Nobuharu Iwasawa, eds. Molecular Catalysts for CO2 Fixation/Reduction. Frontiers Media SA, 2020. http://dx.doi.org/10.3389/978-2-88963-622-8.

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Ma, Jianmin. Photo- and Electro-Catalytic Processes: WaterSplitting, N2 Fixing, CO2 Reduction. Wiley & Sons, Incorporated, John, 2022.

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6

Ma, Jianmin. Photo- and Electro-Catalytic Processes: WaterSplitting, N2 Fixing, CO2 Reduction. Wiley & Sons, Incorporated, John, 2022.

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Ma, Jianmin. Photo- and Electro-Catalytic Processes: WaterSplitting, N2 Fixing, CO2 Reduction. Wiley & Sons, Incorporated, John, 2022.

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8

Ma, Jianmin. Photo- and Electro-Catalytic Processes: WaterSplitting, N2 Fixing, CO2 Reduction. Wiley & Sons, Limited, John, 2021.

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Payne, Emma Kate. The synthesis and characterization of novel platinum and palladium diimene compounds for use as anticancer drugs and CO2 reduction catalyst. 2003.

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Capítulos de livros sobre o assunto "CO2 reduction catalysis"

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Wilcox, Jennifer. "The Role of CO2 Reduction Catalysis in Carbon Capture". In Carbon Capture, 245–55. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-2215-0_8.

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Risbridger, Thomas, e Ross Anderson. "Chapter 2. Bio-inspired and Bio-electrochemical Approaches in CO2 Reduction Catalysis". In Electrochemical Reduction of Carbon Dioxide, 17–62. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781782623809-00017.

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Gan, Lu, David Jennings, Joseph Laureanti e Anne Katherine Jones. "Biomimetic Complexes for Production of Dihydrogen and Reduction of CO2". In Homo- and Heterobimetallic Complexes in Catalysis, 233–72. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/3418_2015_146.

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Haider, Mohd Belal, Mata Mani Tripathi, Zakir Hussain e Rakesh Kumar. "Potential Application of Ionic Liquids and Deep Eutectic Solvents in Reduction of Industrial CO2 Emissions". In Catalysis for Clean Energy and Environmental Sustainability, 643–73. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-65021-6_20.

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Sreejith, S. S., Nithya Mohan e M. R. P. Kurup. "Emergent Catalytic Materials Towards CO2 Reduction". In Emerging Materials, 315–60. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1312-9_9.

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Li, Yuehui, Kathrin Junge e Matthias Beller. "Zinc-Catalyzed Reductions of Unsaturated Compounds". In Zinc Catalysis, 5–32. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527675944.ch2.

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Bonincontro, Danilo, e Elsje Alessandra Quadrelli. "CO2 Reduction Reactions by Rhodium-Based Catalysts". In Topics in Organometallic Chemistry, 263–82. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/3418_2016_172.

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Subramaniam, Jeevithra Dewi, e Pei Meng Woi. "Recent Advancement of Electrocatalyst System in CO2 Reduction". In Nano-catalysts for Energy Applications, 114–36. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003082729-7.

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Ma, Ming, e Wilson A. Smith. "Nanostructured Catalysts for the Electrochemical Reduction of CO2". In Nanostructure Science and Technology, 337–73. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-59662-4_11.

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Boddu, Sanyasinaidu, S. T. Nishanthi e Kamalakannan Kailasam. "Visible-Light Heterogeneous Catalysts for Photocatalytic CO2 Reduction". In Visible Light-Active Photocatalysis, 421–46. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2018. http://dx.doi.org/10.1002/9783527808175.ch15.

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Trabalhos de conferências sobre o assunto "CO2 reduction catalysis"

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Ly, Khoa Hoang. "Operando Vibrational Spectroelectrochemistry for Studying CO2 Reduction Catalysis Promoted by Molecularly-defined Electrocatalysts". In nanoGe Fall Meeting 2019. València: Fundació Scito, 2019. http://dx.doi.org/10.29363/nanoge.ngfm.2019.223.

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Ly, Khoa Hoang. "Operando Vibrational Spectroelectrochemistry for Studying CO2 Reduction Catalysis Promoted by Molecularly-defined Electrocatalysts". In nanoGe Fall Meeting 2019. València: Fundació Scito, 2019. http://dx.doi.org/10.29363/nanoge.nfm.2019.223.

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Chai, Rukaun, Yuetian Liu, Qianjun Liu, Xuan He e Pingtian Fan. "Effect and Mechanism of CO2 Electrochemical Reduction for CCUS-EOR". In SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206135-ms.

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Abstract Unconventional reservoir plays an increasingly important role in the world energy system, but its recovery is always quite low. Therefore, the economic and effective enhanced oil recovery (EOR) technology is urgently required. Moreover, with the aggravation of greenhouse effect, carbon neutrality has become the human consensus. How to sequestrate CO2 more economically and effectively has aroused wide concerns. Carbon Capture, Utilization and Storage (CCUS)-EOR is a win-win technology, which can not only enhance oil recovery but also increase CO2 sequestration efficiency. However, current CCUS-EOR technologies usually face serious gas channeling which finally result in the poor performance on both EOR and CCUS. This study introduced CO2 electrochemical conversion into CCUS-EOR, which successively combines CO2 electrochemical reduction and crude oil electrocatalytic cracking both achieves EOR and CCUS. In this study, multiscale experiments were conducted to study the effect and mechanism of CO2 electrochemical reduction for CCUS-EOR. Firstly, the catalyst and catalytic electrode were synthetized and then were characterized by using scanning electron microscope (SEM) & energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Then, electrolysis experiment & liquid-state nuclear magnetic resonance (1H NMR) experiments were implemented to study the mechanism of CO2 electrochemical reduction. And electrolysis experiment & gas chromatography (GC) & viscosity & density experiments were used to investigate the mechanism of crude oil electrocatalytic cracking. Finally, contact angle and coreflooding experiments were respectively conducted to study the effect of the proposed technology on wettability and CCUS-EOR. SEM & EDS & XPS results confirmed that the high pure SnO2 nanoparticles with the hierarchical, porous structure, and the large surface area were synthetized. Electrolysis & 1H NMR experiment showed that CO2 has converted into formate with the catalysis of SnO2 nanoparticles. Electrolysis & GC & Density & Viscosity experiments indicated that the crude oil was electrocatalytically cracked into the light components (<C20) from the heavy components (C21∼C37). As voltage increases from 2.0V to 7.0V, the intensity of CO2 electrocchemical reduction and crude oil electrocatalytic cracking enhances to maximum at 3.5V (i.e., formate concentration reaches 6.45mmol/L and carbon peak decreases from C17 to C15) and then weakens. Contact angle results indicated that CO2 electrochemical reduction and crude oil electocatalytic cracking work jointly to promote wettability alteration. Thereof, CO2 electrochemical reduction effect is dominant. Coreflooding results indicated that CO2 electrochemical reduction technology has great potential on EOR and CCUS. With the SnO2 catalytic electrode at optimal voltage (3.5V), the additional recovery reaches 9.2% and CO2 sequestration efficiency is as high as 72.07%. This paper introduced CO2 electrochemical conversion into CCUS-EOR, which successfully combines CO2 electrochemical reduction and crude oil electrocatalytic cracking into one technology. It shows great potential on CCUS-EOR and more studies are required to reveal its in-depth mechanisms.
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Morita, Daiki, Yuya Kotani, Qiuyue Zu, Fuka Yoshida, Ratnak Sok e Jin Kusaka. "Acceleration of Fast-SCR Reaction by Eliminating “The Ammonia Blocking Effect”". In CO2 Reduction for Transportation Systems Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2024. http://dx.doi.org/10.4271/2024-37-0001.

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<div class="section abstract"><div class="htmlview paragraph">Electricity, e-fuel and H<sub>2</sub> are considered important recent and future sources of energy for heavy-duty vehicles. Heavy-duty battery electric vehicles (BEV) have many technical challenges. Therefore, internal combustion engines (ICE) powered by e-fuel and hydrogen can be used as an alternative to batteries in heavy-duty trucks. Selective catalytic reduction (SCR) systems are necessary for achieving the goals of zero-emission internal combustion engines that use e-fuel or H<sub>2</sub> as a fuel. The Japanese automotive industry mainly utilizes Cu-Zeolite-based SCR catalysts since vanadium-based catalysts have been difficult to be used to prevent the release of vanadium into the atmosphere due to the relatively low evaporation temperature.</div><div class="htmlview paragraph">This study investigated whether improving the conversion rate by pulsing the NH<sub>3</sub> supply was possible. Experiments were conducted in a mini-reactor with an inflow of simulated exhaust gas to examine the effect of the pulse amplitude, frequency, and duty ratio on the conversion rate when an NH<sub>3</sub> pulse supply was applied to a test piece Cu-chabazite catalyst. The results of the reactor experiment were compared with numerical simulations that considered the detailed surface reaction processes on the catalyst.</div><div class="htmlview paragraph">The experimental results showed that purification of NOx at low temperatures (200°C) improved from 45% to 62% by providing a pulsed supply of reducing agent (NH<sub>3</sub>) rather than a continuous supply. During the time when the pulse supply was off, the decomposition of ammonium nitrate (NH<sub>4</sub>NO<sub>3</sub>) was promoted, enhancing the conversion rate of NOx. The results of the simulations demonstrated that the gas concentrations and conversion rate in the catalyst and unique phenomena at low temperatures, such as the formation and decomposition of NH<sub>4</sub>NO<sub>3</sub> and the ammonia-blocking effect, could be accurately reproduced and simulated.</div></div>
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Domingo Tafalla, Beatriu, Tamal Chatterjee, Federico Franco e Emilio Palomares Gil. "Electro- and Photo-induced Interfacial Charge Transfers in Nanocrystalline Mesoporous TiO2 and TiO2/Iron Porphyrin Sensitized Films Under CO2 Reduction Catalysis". In MATSUS23 & Sustainable Technology Forum València (STECH23). València: FUNDACIO DE LA COMUNITAT VALENCIANA SCITO, 2022. http://dx.doi.org/10.29363/nanoge.matsus.2023.109.

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Tomin, Sebastian, Uwe Wagner e Thomas Koch. "Effect of Dithering on Post-Catalyst Exhaust Gas Composition and on Short Time Regeneration of Deactivated PdO/Al <sub>2</sub> O <sub>3</sub> Catalysts under Real Engine Conditions". In CO2 Reduction for Transportation Systems Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2024. http://dx.doi.org/10.4271/2024-37-0002.

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<div class="section abstract"><div class="htmlview paragraph">Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO<sub>2</sub>. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH<sub>4</sub> most efficiently usually being supported by metal oxides such as aluminium oxide (Al<sub>2</sub>O<sub>3</sub>). Water (H<sub>2</sub>O) contained in the exhaust gas causes strong inhibition on Pd catalysts. In real exhaust gases, not only water vapour but also pollutants and sulphur-containing compounds such as hydrogen sulphide (H<sub>2</sub>S) or sulphur oxides (SO<sub>x</sub>) are poisoning the catalytic converter. Rich pulses decomposing sulphur species adsorbed on Pd-Pt methane oxidation catalysts, enable efficient regeneration of heavily poisoned catalysts. A strategy similar to operation with rich pulses, but with a different motivation, is the use of high-frequency oscillations between lean and rich exhaust gas, so-called dithering, to improve pollutant conversion. A combination of a stoichiometric pulse while simultaneously dithering shows better results in recovery as well as emissions during regeneration than a pure rich pulse.</div></div>
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Berahim, Nor Hafizah, e Akbar Abu Seman. "CO2 Utilization: Converting Waste into Valuable Products". In SPE Asia Pacific Oil & Gas Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210729-ms.

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Abstract Carbon dioxide capture, utilization, and storage (CCUS), which includes conversion to valuable products, is a complex modern issue with many perspectives. In recent years, the idea of using carbon dioxide (CO2) as a feedstock for synthetic applications in the chemical and fuel sectors via reduction reactions has piqued interest. If the hydrogen is created using a renewable energy source, catalytic CO2 hydrogenation is the most viable and appealing alternative among the existing CO2-recycling solutions. CO2 hydrogenation has many chemical paths depending on the catalyst, and multiple value-added hydrocarbons can be generated. This research looks into a catalyst development for converting high CO2 gas field into methane and alcohols. The study focused on catalytic conversion of CO2 to methane over Ru based catalyst while in the case of alcohols using Cu based catalyst. Both catalysts were synthesized via impregnation techniques where the aqueous precursors’ solution were impregnated on the oxide supports, stirred, filtered and washed. The samples were then dried, ground and calcined. The synthesized catalysts were characterized using various analytical techniques (e.g., TPR, FESEM, N2 adsorption-desorption, XRD) for their physicochemical properties. The catalytic performance in CO2 hydrogenation was performed using a fixed bed reactor at various factors such as temperature, pressure, feed gas ratio and space velocity. The experimental findings indicate that conversion of CO2 to methane over Ru based catalyst resulted in &gt;84% CO2 conversion with 99% methane selectivity in the range of temperature 280 – 320 °C and at atmospheric pressure. In the case of hydrogenation of CO2 to alcohols, the catalytic performance of Cu based catalyst exhibited CO2 conversion of &gt;11% and selectivity towards alcohols, C1 and C2, both at 4% with reaction temperature of 250 °C and pressure 30 bar. These findings revealed that methane could easily be formed from CO2 as compared to alcohol. However, both technology conversions are dependent on the catalyst selection and its’ activity. Process parameters need to be optimized to maximize targeted product formation and suppress the side products.
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Ferreri, Paolo, Giuseppe Cerrelli, Yong Miao, Stefano Pellegrino e Lorenzo Bianchi. "Conventional and Electrically Heated Diesel Oxidation Catalyst Physical Based Modeling". In CO2 Reduction for Transportation Systems Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2018. http://dx.doi.org/10.4271/2018-37-0010.

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Polaert, Isabelle, Bachar Alrafei, Jose Delgado-Liriano e Alain Ledoux. "Synergetic effect of microwave plasma and catalysts in CO2 methanation". In Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9806.

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The reduction of CO2 concentration in our atmosphere consists in a big challenge for researchers, who are trying to explore novel technologies in order to transform CO2 into high added-value products. CO2 conversion into methane using microwave plasma (MWP) manifests as a very promising solution due to the ease of transport of methane and its storage. Microwave plasma represents a source of high-energy electrons, active ions and radicals that enhance or enable chemical reaction. It can be supplied by electricity generated from renewable resources. Then, MWP does not require any electrode to be generated and thus, the cost of those electrodes and of maintenance is reduced compared to glow discharge or DBD plasmas. MWP also can be generated over wide range of pressure (between 10 mbar-1bar). In addition, in the case of MWP, more electrons and active species are produced in comparison with other type of plasma[1–4]. MWP is a very suitable medium for this chemical reaction and leads to an efficient dissociation of CO2. The catalytic reduction of CO2 with H2 using MWP has been investigated in this work and the synergetic effects between the plasma and several catalysts were studied. First, the reaction was carried out without any catalysts and the effect of CO2/H2 ratio, total flow rate and input energy were evaluated. Then, a microwave generated plasma process was coupled with several Nickel catalysts that we prepared and characterized [5] in order to lead the reaction into methane formation. Multiple configurations were studied by changing the position of the catalyst bed. Obtained results were compared with conventional catalytic tests made with the same catalysts. It was found that the conversion of CO2 and energy efficiency increased using plasma assisted catalytic methanation of CO2 in comparison with conventional process. Operating conditions were studied in order to optimize methane production and energy efficiency of Plasma-catalytic process. References Qin, Y., G. Niu, X. Wang, D. Luo, Y. Duan, J. CO2 Util., 2018, 28, 283–291. De la Fuente, J.F., S.H. Moreno, A.I. Stankiewicz, G.D. Stefanidis, Int J Hydrogen Energy, 2016, 41, 21067–21077. Ashford, B., X. Tu, Curr Opin Green Sustain Chem, 2017, 3, 45–49. Vesel, A., M. Mozetic, A. Drenik, M. Balat-Pichelin, Chem Phys., 2011, 382, 127–131. Alrafei, B., I. Polaert, A. Ledoux, F. Azzolina-Jury, Catal. Today, Available online 12 March 2019, In Press, Accepted Manuscript. https://doi.org/10.1016/j.cattod.2019.03.026
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Hofstetter, Johannes, Paul Boucharel, Frank Atzler e Georg Wachtmeister. "Fuel Consumption and Emission Reduction for Hybrid Electric Vehicles with Electrically Heated Catalyst". In CO2 Reduction for Transportation Systems Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2020. http://dx.doi.org/10.4271/2020-37-0017.

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Relatórios de organizações sobre o assunto "CO2 reduction catalysis"

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Badrinarayanan e Olsen. PR-179-11201-R01 Performance Evaluation of Multiple Oxidation Catalysts on a Lean Burn Natural Gas Engine. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), agosto de 2012. http://dx.doi.org/10.55274/r0010772.

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Two-way catalysts or oxidation catalysts are the common after-treatment systems used on lean burn natural gas engines to reduce CO, VOCs and formaldehyde emissions. The study evaluates the performance of oxidation catalysts from commercial vendors for varying catalyst temperature and space velocity. For this study, a part of the exhaust from a Waukesha VGF-18 GL lean burn natural gas engine was flowed through a catalyst slipstream system to assess the performance of the oxidation catalysts. The slipstream is used to reduce the size of the catalysts and to allow precise control of temperature and space velocity. Analyzers used include Rosemount 5-gas emissions bench, Nicolet Fourier Transform Infra-Red spectrometer and HP 5890 Series II Gas Chromatograph. The oxidation catalysts were degreened at 1200oF (650oC) for 24 hours prior to performance testing. The reduction efficencies for the emission species varied among the oxidation catalysts tested from different vendors. Most oxidation catalysts showed over 90% maximum reduction efficiencies on CO, VOCs and formaldehyde. VOC reduction efficiency was limited by poor propane emission reduction efficiency at the catalyst temperatures tested. Saturated hydrocarbons such as propane showed low reduction efficiencies on all oxidation catalysts due to high activation energy. Variation in space velocity showed very little effect on the conversion efficiencies. Most species showed over 90% conversion efficiency during the space velocity sweep. Adding more catalyst volume may not increase the reduction efficiency of emission species. Varying cell density showed very little effect on performance of the oxidation catalysts. The friction factor correlation showed the friction factor for flow through a single channel is inversely proportional to cell density.
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Betley, Theodore, M. Lalonde, G. T. Sazama e A. B. Scharf. Bifunctional Catalysts for CO2 Reduction. Fort Belvoir, VA: Defense Technical Information Center, setembro de 2014. http://dx.doi.org/10.21236/ada610432.

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Sariciftci, Niyazi Serdar. CO2 Recycling: The Conversion of Renewable Energy into Chemical Fuels. AsiaChem Magazine, novembro de 2020. http://dx.doi.org/10.51167/acm00011.

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We want to bring the idea of conversion of CO2 into synthetic fuels (CO2 recycling) into attention, as a possible approach for transportable storage of renewable energy. Recycling of CO2 by homogeneous and/or heterogeneous catalytic approaches have been investigated with increasing emphasis within the scientific community. In the last decades, especially using organic and bioorganic systems towards CO2 reduction has attracted great interest. Chemical, electrochemical, photoelectrochemical, and bioelectrochemical approaches are discussed vividly as new routes towards the conversion of CO2 into synthetic fuels and/or useful chemicals in the recent literature. Here we want to especially emphasize the new developments in bio-electrocatalysis with some recent examples.
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Simmons. L51814 Survey Of Dry Low NOx Combustor Experience. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), setembro de 1999. http://dx.doi.org/10.55274/r0010207.

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Air pollution has become a major public issue and it is now evident that unburned hydrocarbons, CO, and NOx must meet increasingly restrictive standards. The emissions of nitrogen oxides by gas turbines are of concern because of their high toxicity and their role in the formation of photochemical smog. The formation of NOx occurs in a gas-fired gas turbine when combustion temperatures exceed a critical level for sufficient time to allow atmospheric nitrogen and oxygen to combine. For those gas turbine applications where steam or ultra-pure water are readily available, then steam or water injection are preferable NOx control strategies. Because these attributes are usually not available at pipeline compression stations, the turbine operators in the pipeline industry have chosen to control emissions by a dry combustion process. An alternative would be a catalytic reduction of the NOx generated in the exhaust gas but this requires an investment in SCR hardware and continuous use of ammonia, which adds to operating costs. Historically, dry low emissions (DLE) systems have experienced a greater than expected number of start-up problems as new products were introduced to the marketplace. A need of the gas pipeline industry is to identify the operating problems experienced with DLE systems, to link these problems to their most probable cause, to estimate costs incurred, and to glean strategies for avoiding future problems. A comprehensive PRCI sponsored survey of operators and manufacturers was completed which provides assistance to gas turbine operators in making NOx control procurement decisions and for budgeting operations and maintenance costs. This first ever detailed study provides information on typical operating costs and problems incurred with the currently operating DLE systems and serves as a guide for individual companies in the selection of cost effective low NOx combustion systems from available components offered by the OEM and after-market suppliers. The information developed by this report is intended to guide operators in estimating maintenance and repair costs to establish a lifetime cost of operation.
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