Download or read book Reverse Water Gas Shift Reaction Over Supported Cu Ni Nanoparticle Catalysts written by Maxime Lortie and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Supported Copper Nickel and Copper nickel Nanoparticle Catalysts for Low Temperature Water gas shift Reaction written by Jiann-Horng Lin and published by . This book was released on 2012 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen is being considered worldwide as a future replacement for gasoline, diesel fuel, natural gas in both the transportation and non-transportation sectors. Hydrogen is a versatile energy carrier that can be produced from a variety of widely available primary energy sources, including coal, natural gas, biomass, solar, wind, and nuclear power. Coal, the most abundant fossil fuel on the planet, is being looked at as the possible future major source of H2, due to the development of the integrated gasification combined cycle (IGCC) and integrated gasification fuel cell technologies (IGFC). The gasification of coal produces syngas consisting of predominately carbon monoxide and hydrogen with some remaining hydrocarbons, carbon dioxide and water. Then, the water-gas shift reaction is used to convert CO to CO2 and additional hydrogen. The present work describes the synthesis of model Cu, Ni and Cu-Ni catalysts prepared from metal colloids, and compares their behavior in the WGS reaction to that of traditional impregnation catalysts. Initially, we systematically explored the performance of traditional Cu, Ni and Cu-Ni WGS catalysts made by impregnation methods. Various bimetallic Cu-Ni catalysts were prepared by supported impregnation and compared to monometallic Cu and Ni catalysts. The presence of Cu in bimetallic catalysts suppressed undesirable methanation side reaction, while the Ni component was important for high WGS activity. Colloidal Cu, Ni and Cu-Ni alloy nanoparticles obtained by chemical reduction were deposited onto alumina to prepare supported catalysts. The resulting Cu and Ni nanoparticle catalysts were found to be 2.5 times more active in the WGS reaction per unit mass of active metal as compared to catalysts prepared by the conventional impregnation technique. The powder XRD and HAADF-STEM provided evidence supporting the formation of Cu-Ni particles containing the Cu core and Cu-Ni alloy shell. The XPS data indicated surface segregation of Cu in the bimetallic Cu-Ni catalysts after reduction. The colloidal Cu5Ni5 alloy catalyst exhibited the WGS reaction rate that was higher than that observed over colloidal Cu and Ni catalysts indicating for the very first time a favorable bimetallic effect for the Cu-Ni system. The presence of Cu in these bimetallic catalysts induced favorable structural and electronic effects not only for enhancing the WGS activity, but also for suppressing methane yield. Bimetallic Cu-Ni catalysts possessing a core-shell structure were synthesized that provided important insights into their structure-activity relationships in the WGS reaction. We employed a successive reduction route to synthesize Cu@Ni and Ni@Cu core-shell nanoparticles and deposited them onto alumina support to obtain supported bimetallic catalysts. The powder XRD patterns, CO chemisorption data, and UV-vis spectra indicated the formation of core-shell structures in the bimetallic Cu-Ni nanoparticles. Cu@Ni catalysts showed similar WGS activities to supported Ni catalysts but lower methanation activity. Suppressed methanation activity observed for Cu@Ni nanoparticles may be due to Cu segregation to the surface. Supported Ni@Cu catalysts displayed WGS activity comparable to supported Cu catalysts. Therefore, these findings strongly suggested that supported Cu, Ni and Cu-Ni alloy nanoparticle catalysts prepared from metal colloids are very promising as highly active WGS catalysts.

Download or read book Engineering Solutions for CO2 Conversion written by Tomas Ramirez Reina and published by John Wiley & Sons. This book was released on 2021-07-19 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive guide that offers a review of the current technologies that tackle CO2 emissions The race to reduce CO2 emissions continues to be an urgent global challenge. "Engineering Solutions for CO2 Conversion" offers a thorough guide to the most current technologies designed to mitigate CO2 emissions ranging from CO2 capture to CO2 utilization approaches. With contributions from an international panel representing a wide range of expertise, this book contains a multidisciplinary toolkit that covers the myriad aspects of CO2 conversion strategies. Comprehensive in scope, it explores the chemical, physical, engineering and economical facets of CO2 conversion. "Engineering Solutions for CO2 Conversion" explores a broad range of topics including linking CFD and process simulations, membranes technologies for efficient CO2 capture-conversion, biogas sweetening technologies, plasma-assisted conversion of CO2, and much more. This important resource: * Addresses a pressing concern of global environmental damage, caused by the greenhouse gases emissions from fossil fuels * Contains a review of the most current developments on the various aspects of CO2 capture and utilization strategies * Incldues information on chemical, physical, engineering and economical facets of CO2 capture and utilization * Offers in-depth insight into materials design, processing characterization, and computer modeling with respect to CO2 capture and conversion Written for catalytic chemists, electrochemists, process engineers, chemical engineers, chemists in industry, photochemists, environmental chemists, theoretical chemists, environmental officers, "Engineering Solutions for CO2 Conversion" provides the most current and expert information on the many aspects and challenges of CO2 conversion.

Download or read book Nanoparticle Design and Characterization for Catalytic Applications in Sustainable Chemistry written by Rafael Luque and published by Royal Society of Chemistry. This book was released on 2019-10-05 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an introduction to the preparation and characterisation of nanomaterials and their design for specific catalytic applications.

Download or read book Molecular Spectroscopy of Oxide Catalyst Surfaces written by Anatoli Davydov and published by John Wiley & Sons. This book was released on 2003-06-27 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt: As in the study of transition metal complexes in solution, molecular spectroscopic methods - principally the infrared, ultraviolet/visible and electron spin resonance spectroscopies - have played key roles in establishing the concepts of coordination chemistry occurring at the surfaces of solids. This book describes the development of the principals of coordination chemistry of oxide surfaces using analyses of data obtained by these methods. The nature, properties, concentration of the surface adsorption centers and their influence on the character of interaction with different molecules are investigated. The book commences with an account of the basic theoretical principles and experimental techniques of the various spectroscopy methods, with special attention devoted to in situ measurements where the oxide or catalyst sample is in contact with the adsorbate or the reactant. A detailed account is presented of the methods for characterizing the oxidation state and degree of coordination of surface cations and oxygen anions by the adsorption of probe molecules. The complexation of many inorganic, organometallic and organic molecules with different oxide systems is critically examined, and a classification of formed surface compounds, based on the interaction with definite type of adsorption centers, is given. Possible mechanisms of numerous catalytic reactions, including the transformation of organic molecules over acidic catalysts via the carboionic mechanism, are discussed using the spectroscopic identifications of reaction intermediates. A comprehensive analysis of the literature on the interpretation of the spectra of surface compounds on oxides is presented. This highly illustrated and extensively referenced volume is intended for specialists working in the fields of surface physical chemistry, surface and materials sciences, and adsorption phenomena and is essential reading for those involved in the heterogeneous catalysis by transition metal-oxides.

Download or read book Water Gas Shift Reaction written by Panagiotis Smirniotis and published by Elsevier. This book was released on 2015-06-11 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water Gas Shift Reaction: Research Developments and Applications outlines the importance of hydrogen as a future fuel, along with the various hydrogen production methods. The book explains the development of catalysts for Water Gas Shift (WGS) reaction at different temperatures and steam/CO ratios, and also discussing the effect of different dopants on the WGS activity of iron oxide and the promotion and inhibition roles of the dopants on the WGS activity of iron oxide are explained. In addition, the book describes extensive characterization of modified ferrite catalysts, especially with Mossbauer spectroscopy and its advantage in understanding properties of metal doped ferrite catalysts, the exact dopant location, and its effect on electron hopping capability and WGS activity of Fe redox couple. Outlines the importance of the Water Gas Shift Reaction and its application for hydrogen production Provides detailed information on potential catalysts, their development, and their pros and cons, giving the reader insights on how modified ferrite catalysts work at different temperatures and different steam to CO ratios Reviews hydrogen technology, its current importance, and production methods Presents a clear presentation of the topics with many graphics and tables Offers basic and advanced knowledge of catalysts characterization instrumental techniques

Download or read book Greener Fischer Tropsch Processes written by Peter M. Maitlis and published by John Wiley & Sons. This book was released on 2013-01-30 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Greener Fischer-Tropsch Processes How can we use our carbon-based resources in the most responsible manner? How can we most efficiently transform natural gas, coal, or biomass into diesel, jet fuel or gasoline to drive our machines? The Big Questions today are energy-related, and the Fischer-Tropsch process provides industrially tested solutions. This book offers a comprehensive and up-to-date overview of the Fischer-Tropsch process, from the basic science and engineering to commercial issues. It covers industrial, economic, environmental, and fundamental aspects, with a specific focus on “green” concepts such as sustainability, process improvement, waste-reduction, and environmental care. The result is a practical reference for researchers, engineers, and financial analysts working in the energy sector, who are interested in carbon conversion, fuel processing or synthetic fuel technologies. It is also an ideal introductory book on the Fischer-Tropsch process for graduate courses in chemistry and chemical engineering.

Download or read book Metal Support Interaction and Electrochemical Promotion of Nano Structured Catalysts for the Reverse Water Gas Shift Reaction written by Christopher Panaritis and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The continued release of fossil-fuel derived carbon dioxide (CO2) emissions into our atmosphere led humanity into a climate and ecological crisis. Converting CO2 into valuable chemicals and fuels will replace and diminish the need for fossil fuel-derived products. Through the use of a catalyst, CO2 can be transformed into a commodity chemical by the reverse water gas shift (RWGS) reaction, where CO2 reacts with renewable hydrogen (H2) to form carbon monoxide (CO). CO then acts as the source molecule in the Fischer-Tropsch (FT) synthesis to form a range of hydrocarbons to manufacture chemicals and fuels. While the FT synthesis is a mature process, the conversion of CO2 into CO has yet to be made commercially available due to the constraints associated with high reaction temperature and catalytic stability. Noble metal ruthenium (Ru) has been widely used for the RWGS reaction due to its high catalytic activity, however, several constraints hinder its practical use, associated with its high cost and its susceptibility to deactivation. The doping or bimetallic use of non-noble metals iron (Fe) and cobalt (Co) is an attractive option to lower material cost and tailor the selectivity of the CO2 conversion towards the RWGS reaction without compromising catalytic activity. Furthermore, employing nanostructured catalysts as nanoparticles is a viable solution to further lower the amount of metal used and utilize the highly active surface area of the catalyst. Dispersing nanoparticles on ionically conductive supports/solid electrolytes which contain species like O2−, H+, Na+, and K+, provide an approach to further enhance the reaction. This phenomenon is referred to as metal-support interaction (MSI), allowing for the ions to back spillover from the support and onto the catalyst surface. An in-situ approach referred to as Non-Faradaic Modification of catalytic activity (NEMCA), also known as electrochemical promotion of catalysis (EPOC) is used to in-situ control the movement of ionic species from the solid electrolyte to and away from the catalyst. Both the MSI and EPOC phenomena have been shown to be functionally equivalent, meaning the ionic species act to alter the work function of the catalyst by forming an effective neutral double layer on the surface, which in turn alters the binding energy of the reactant and intermediate species to promote the reaction. The main objective of this work is to develop a catalyst that is highly active and selective to the RWGS reaction at low temperatures (

Download or read book Plasma Catalysis written by Annemie Bogaerts and published by MDPI. This book was released on 2019-04-02 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma catalysis is gaining increasing interest for various gas conversion applications, such as CO2 conversion into value-added chemicals and fuels, N2 fixation for the synthesis of NH3 or NOx, methane conversion into higher hydrocarbons or oxygenates. It is also widely used for air pollution control (e.g., VOC remediation). Plasma catalysis allows thermodynamically difficult reactions to proceed at ambient pressure and temperature, due to activation of the gas molecules by energetic electrons created in the plasma. However, plasma is very reactive but not selective, and thus a catalyst is needed to improve the selectivity. In spite of the growing interest in plasma catalysis, the underlying mechanisms of the (possible) synergy between plasma and catalyst are not yet fully understood. Indeed, plasma catalysis is quite complicated, as the plasma will affect the catalyst and vice versa. Moreover, due to the reactive plasma environment, the most suitable catalysts will probably be different from thermal catalysts. More research is needed to better understand the plasma–catalyst interactions, in order to further improve the applications.

Download or read book Strong Metal support Interactions written by R. T. K. Baker and published by . This book was released on 1986 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Studies of the Water gas Shift Reaction Over Supported Gold and Platinum Catalysts written by Steven Taylor Evans and published by . This book was released on 2004 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Economy Based on Carbon Dioxide and Water written by Michele Aresta and published by Springer. This book was released on 2019-07-01 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is devoted to CO2 capture and utilization (CCU) from a green, biotechnological and economic perspective, and presents the potential of, and the bottlenecks and breakthroughs in converting a stable molecule such as CO2 into specialty chemicals and materials or energy-rich compounds. The use of renewable energy (solar, wind, geothermal, hydro) and non-fossil hydrogen is a must for converting large volumes of CO2 into energy products, and as such, the authors explore and compare the availability of hydrogen from water using these sources with that using oil or methane. Divided into 13 chapters, the book offers an analysis of the conditions under which CO2 utilization is possible, and discusses CO2 capture from concentrated sources and the atmosphere. It also analyzes the technological (non-chemical) uses of CO2, carbonation of basic minerals and industrial sludge, and the microbial-catalytic-electrochemical-photoelectrochemical-plasma conversion of CO2 into chemicals and energy products. Further, the book provides examples of advanced bioelectrochemical syntheses and RuBisCO engineering, as well as a techno-energetic and economic analysis of CCU. Written by leading international experts, this book offers a unique perspective on the potential of the various technologies discussed, and a vision for a sustainable future. Intended for graduates with a good understanding of chemistry, catalysis, biotechnology, electrochemistry and photochemistry, it particularly appeals to researchers (in academia and industry) and university teachers.

Download or read book Metal Nanoparticles for Catalysis written by Franklin Tao and published by Royal Society of Chemistry. This book was released on 2014-06-12 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis is a central topic in chemical transformation and energy conversion. Thanks to the spectacular achievements of colloidal chemistry and the synthesis of nanomaterials over the last two decades, there have also been significant advances in nanoparticle catalysis. Catalysis on different metal nanostructures with well-defined structures and composition has been extensively studied. Metal nanocrystals synthesized with colloidal chemistry exhibit different catalytic performances in contrast to metal nanoparticles prepared with impregnation or deposition precipitation. Additionally, theoretical approaches in predicting catalysis performance and understanding catalytic mechanism on these metal nanocatalysts have made significant progress. Metal Nanoparticles for Catalysis is a comprehensive text on catalysis on Nanoparticles, looking at both their synthesis and applications. Chapter topics include nanoreactor catalysis; Pd nanoparticles in C-C coupling reactions; metal salt-based gold nanocatalysts; theoretical insights into metal nanocatalysts; and nanoparticle mediated clock reaction. This book bridges the gap between nanomaterials synthesis and characterization, and catalysis. As such, this text will be a valuable resource for postgraduate students and researchers in these exciting fields.

Download or read book Advanced Heterogeneous Catalysts Volume 1 written by Sudarsanam Putla and published by ACS Symposium. This book was released on 2021-05-07 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances and applications of nanosized catalysts Over the last five years, tremendous advances have been made in heterogeneous catalysis. In particular, catalysts' design from the bulk to nano-scale (1-100 nm), with desirable active sites, has received great attention in current catalysis research with the aim to fill the gap between homogeneous and heterogeneous catalysis. This volume focuses on applications of nanosized catalysts. Articles describe characterization, synthesis, and applications in biomass conversion, auto-exhaust purification, selective oxidation/hydrogenation, syngas conversion, and other important reactions. Readers will find examples of catalysts designed to be tunable for specific outcomes, inspiring their research. Scientists and engineers in chemistry, materials science, nanotechnology, and chemical engineering will find this volume useful.

Download or read book Study of Cu ZnO Ga2O3 and MoxC based Catalysts for the Reverse Water Gas Shift Reaction written by Xianyun Liu and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays, serious concern exists about atmospheric CO2 increase related with environmental impact and climate change. The reuse of CO2 through its chemical recycling is a promising route, which could contribute to the decrease of globally emitted CO2. Today CO2 is not only considered a waste, CO2 can be also conveniently used as raw material for industrial applications, and the development of new or improved processes for its use can contribute for a sustainable development. CO2 is a molecule which is thermodynamically stable, and its activation requires high energy input to overcome the energy barrier for the dissociation of C=O bond. However, CO2 can be selectively activated in the presence of H2 through catalytic processes, under appropriate conditions of pressure and temperature. In this doctoral research project, the main objective is related with the development of new catalysts for efficient CO2 conversion to CO via the reverse water gas shift reaction (RWGS) under mild conditions. For such purposes, new multicomponent CuZnOGa2O3MxOy (M=Al, Zr) and MoxC-based catalysts were prepared, deeply characterized and studied under different experimental conditions in the RWGS reaction. CuZnxGaM (M=Al, Zr) catalysts were prepared using a surfactant-free sol-gel method. CuZnxGaZr showed higher surface area, easier reducibility of CuO and a higher amount of surface Cu, Zn and Ga species than CuZn and CuZnxGaAl. Reduced catalysts were highly performant in the RWGS reaction at 250-270 °C, 3 MPa using a CO2/H2/N2=1/3/1 reactant mixture. CuZnxGaZr were more active than CuZn and CuZnxGaAl catalysts. This is related with a synergetic effect of Cu and the oxygen vacancies at the Cu-Support interface. The RWGS reaction carried out at atmospheric pressure using a CO2/H2/N2=1/3/1 reactant mixture over the CuZn3GaZr, resulted in a CO selectivity close to 100% at 325 °C under a CO2 conversion of 16.8%. The apparent Ea determined in the 275-325 °C range for CO production over CuZn3GaZr catalyst was 70.9±3.7 kJ/mol. On the other hand, new MoxC-based catalysts were prepared using sol-gel routes with different carbon precursors and without additional H2 and/or CH4 reducing thermal treatment. Bulk MoxC catalysts (MoxC-U, MoxC-CA and MoxC-E), gamma-Al2O3-, TiO2-, SBA-15- and SiO2-supported MoxC-U catalysts and, Cu- and Co-modified MoxC-U and MoxC/gamma-Al2O3 catalysts have been studied in the RWGS (CO2/H2/N2=1/3/1 and CO2/H2/N2=1/3/1) reaction in the 275-400 °C range and atmospheric pressure. MoxC-CA having hcp-Mo2C, fcc-Mo2C and/or fcc-MoC and the highest SBET (14.5 m2/g) showed the best performance. A CO yield of 41.8 mol/Kgcat·h, with 98% selectivity to CO was obtained at 400 °C using a CO2/H2/N2=1/3/1 mixture. The apparent Ea determined in the 275-325 °C range for CO production was 64.8+/-4.1 kJ/mol. MoxC-U showed only the presence of polycrystalline hcp-Mo2C. Its characteristics and catalytic properties were deeply analyzed and successfully interpreted in the light of theoretical studies carried out under a collaborative work. The adsorption heat of CO2 on MoxC-U was -3.2 eV. Over hcp-Mo2C, CO2 dissociates at 35 °C to CO+O surface species. Under RWGS conditions, the reaction proceeded by subsequent hydrogenation, and CO and H2O formation. Over MoxC-U, using a CO2/H2/N2=1/1/3 reactant mixture, the CO selectivity at 400 °C, 0.1 MPa, was 99.5% (CO2 conversion=16%). An apparent Ea of 55.2+/- 2.3 kJ/mol for CO production was determined for this catalyst in the 275-325 °C range. Different MoxC phases were obtained in gamma-Al2O3-, TiO2-, SBA-15- and SiO2-supported MoxC-U catalysts as a function of the support. In general, for supported MoxC catalysts, a higher CO production (mol CO/mol Mo·h) when compared with that of MoxC-U was found. 25MoxC/SiO2 catalyst, which showed the presence of hcp-Mo2C and fcc-MoC, was the most performant for CO production; it produced 17.0 mol CO/mol Mo·h at 400 °C, 0.1 MPa and CO2/H2/N2=1/3/1. Using a CO2/H2/N2=1/1/3 reaction mixture, the CO yield was up to 5 times higher than that obtained over the bulk MoxC-U catalyst.

Download or read book The Water gas Shift Reaction Over Model Copper Catalysts written by Joseph Campbell and published by . This book was released on 1991 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrochemical Activation of Catalysis written by Costas G. Vayenas and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: I knew nothing of the work of C. G. Vayenas on NEMCA until the early nineties. Then I learned from a paper of his idea (gas interface reactions could be catalyzed electrochemically), which seemed quite marvelous; but I did not understand how it worked. Consequently, I decided to correspond with Professor Vayenas in Patras, Greece, to reach a better understanding of this concept. I think that my early papers (1946, 1947, and 1957), on the relationship between the work function of metal surfaces and electron transfer reactions thereat to particles in solution, held me in good stead to be receptive to what Vayenas told me. As the electrode potential changes, so of course, does the work function at the interface, and gas metal reactions there involve adsorbed particles which have bonding to the surface. Whether electron transfer is complete in such a case, or whether the effect is on the desorption of radicals, the work function determines the strength of their bonding, and if one varies the work function by varying the electrode potential, one can vary the reaction rate at the interface. I got the idea. After that, it has been smooth sailing. Dr. Vayenas wrote a seminal article in Modern Aspects of Electrochemistry, Number 29, and brought the field into the public eye. It has since grown and its usefulness in chemical catalytic reactions has been demonstrated and verified worldwide.