Download or read book Selective Oxidation and Oxidative Dehydrogenation Reactions Using Niobium Based Catalysts written by Aled Mathew Davies and published by . This book was released on 2009 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Developments in Selective Oxidation II written by V. Cortés Corberán and published by Elsevier. This book was released on 1994-06-21 with total page 907 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains invited papers and communications presented at the Second World Congress and Fourth European Workshop Meeting on New Developments in Selective Oxidation. The purpose of the meeting was to present new topics and recent advances as well as the discussion of new aspects of fundamental and applied aspects of partial selective oxidation in heterogeneous and homogeneous catalysis. The following topics were discussed: New processes for fine chemicals by catalytic oxidation; Recent developments in surface chemistry of oxide catalysts; Novel catalytic systems and preparation methods; Heterogenized homogeneous oxidation catalysts; Selective oxidation and oxidative dehydrogenation of alkanes; New industrial developments based on catalytic oxidation reactions; Bio-, photo-, and electro-catalytic oxidation; Oxidation by other agents than dioxygen; Bifunctional metal-on-metal oxide catalysts for selective oxidation.This book provides a valuable set of data on selective oxidation reactions which will be extremely useful to catalyst and related practitioners, whether fundamentalists or highly applied, and to process engineers who wish to evaluate current findings in this field.

Download or read book Catalytic Selective Oxidation written by S. Ted Oyama and published by American Chemical Society. This book was released on 1993 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discusses the most recent advances in the theories and concepts of selective oxidation technology. Examines the synthesis, characterization, and performance of new catalytic materials used in the oxidation of hydrocarbons in the range of C[1 to C[4. Highlights the use of transition metal oxides in one of several redox states in industrial oxidation processes. Also presents state-of-the-art developments in engineering and applications to new processes.

Download or read book New Developments in Selective Oxidation by Heterogeneous Catalysis written by P. Ruiz and published by Elsevier. This book was released on 1992-02-06 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains invited papers and communications presented at the Third European Workshop Meeting on Selective Oxidation by Heterogeneous Catalysis. The purpose of the meeting was to present recent results and to discuss new aspects of partial oxidation by heterogeneous catalysis. The following topics were discussed: Novel processes for obtaining new fine chemicals by catalytic partial oxidation; selective oxidation and oxidative dehydrogenation of alkanes; new catalysts and advances in preparation methods of oxidation catalysts; new phenomena in partial oxidation and new aspects of surface chemistry in oxide catalysts; new applications of physicochemical methods for characterization of oxide catalysts; oxidation with other agents than oxygen and catalytic oxidation of carbohydrates. This book will provide a valuable set of data on reactions of selective oxidation which will be extremely useful to catalyst and related practitioners, whether fundamentalists or highly applied, and to process engineers who wish to evaluate current findings in this field. The wide-range approach to reactions of selective oxidation will disseminate knowledge in specialized areas of selective oxidation and encourage innovation and creativity.

Download or read book Niobium Oxide Based Catalysts for the Selective Oxidation of Hydrocarbons written by Preabjot Kaur Singh and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Catalytic Selective Oxidation written by S. Ted Oyama and published by . This book was released on 1993 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selective Oxidation by Heterogeneous Catalysis written by Gabriele Centi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 519 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selective Oxidation by Heterogeneous Catalysis covers one of the major areas of industrial petrochemical production, outlining open questions and new opportunities. It gives keys for the interpretation and analysis of data and design of new catalysts and reactions, and provides guidelines for future research. A distinctive feature of this book is the use of concept by example. Rather than reporting an overview of the literature results, the authors have selected some representative examples, the in-depth analysis of which makes it possible to clarify the fundamental, but new concepts necessary for a better understanding of the new opportunities in this field and the design of new catalysts or catalytic reactions. Attention is given not only to the catalyst itself, but also to the use of the catalyst inside the process, thus evidencing the relationship between catalyst design and engineering aspects of the process. This book provides suggestions for new innovative directions of research and indications on how to reconsider the field of selective oxidation from different perspectives, outlining that is not a mature field of research, but that new important breakthroughs can be derived from fundamental and applied research. Suggestions are offered on how to use less conventional approaches in terms of both catalyst design and analysis of the data.

Download or read book New Developments in Selective Oxidation by Heterogeneous Catalysis written by Patricio Ruiz and published by Elsevier Science Limited. This book was released on 1992-01-01 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains invited papers and communications presented at the Third European Workshop Meeting on Selective Oxidation by Heterogeneous Catalysis. The purpose of the meeting was to present recent results and to discuss new aspects of partial oxidation by heterogeneous catalysis. The following topics were discussed: Novel processes for obtaining new fine chemicals by catalytic partial oxidation; selective oxidation and oxidative dehydrogenation of alkanes; new catalysts and advances in preparation methods of oxidation catalysts; new phenomena in partial oxidation and new aspects of surface chemistry in oxide catalysts; new applications of physicochemical methods for characterization of oxide catalysts; oxidation with other agents than oxygen and catalytic oxidation of carbohydrates. This book will provide a valuable set of data on reactions of selective oxidation which will be extremely useful to catalyst and related practitioners, whether fundamentalists or highly applied, and to process engineers who wish to evaluate current findings in this field. The wide-range approach to reactions of selective oxidation will disseminate knowledge in specialized areas of selective oxidation and encourage innovation and creativity.

Download or read book Selective Oxidation of Hydrocarbons written by D. J. Hucknall and published by . This book was released on 1974 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Niobium Species in Heterogeneous Catalysts Used for Oxiditation Processes Selected Aspects written by Maria Ziolek and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work is devoted to the discoveries and/or knowledge developed in the past years in the area of the application of heterogeneous catalysts containing niobium for selective oxidation in gas and liquid phases by the use of different oxidants. This book presents a general overview of the role of niobium species located in crystalline and amorphous solids in catalytic oxidation processes. The important ability of niobium to combine with many elements to form new compounds determines the unique properties of niobium containing catalysts. Two main roles of niobium species in heterogeneous catalysis are considered: as catalytic active centers and as promoters..

Download or read book Mechanistic Insights on the Oxidative Dehydrogenation of Light Alkanes Catalyzed by Boron based Catalysts written by Juan Mauricio Venegas and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Light olefins such as ethylene and propylene form the foundation of the modern chemical industry, with yearly production volumes well into the hundreds of millions of metric tons. Currently, these light olefins are mainly produced via energy-intensive steam cracking. Alternatively, oxidative dehydrogenation (ODH) of light alkanes to produce olefins allows for lower operation temperatures and extended catalyst lifetimes, providing valuable process efficiencies. This route has led to significant research interest due to the wide availability of natural gas from shale deposits. Advances in this area have still not yielded catalysts that are sufficiently selective to olefins for industrial implementation, and ODH still remains a holy grail of selective alkane oxidation research. Research into selective heterogeneous catalysts for the ODH of propane has led to the extensive use of vanadium oxide-based catalysts, and studies on the surface mechanism involved have been used to improve the catalytic activity of the material. Despite decades of research, however, selectivity towards propylene has not proven satisfactory at industrially-relevant conversions. In this thesis, I will present the serendipitous discovery and subsequent development of hexagonal boron nitride (hBN) and other boron-containing catalysts as selective ODH catalysts. Specifically, I will illustrate the evolution of our understanding of the chemical origin of the reactivity of these materials, which until our initial discovery were deemed chemically inert. By combining reactivity studies with spectroscopic characterization highlighted a unique interaction between boron and oxiygen that differs from that of metal oxides. This methodical characterization of catalytic activity and structural changes of hBN during ODH prompted us to zero in on oxidized boron species, not hBN itself, as the true catalyst of alkane oxidation. In turn, this discovery led us to describe a whole class of B-containing materials that share (and often improve upon) the catalytic performance of hBN. At this point, we decided to step away from material studies and instead improve our understanding on how the catalytic performance of hBN is affected by reactor operating parameters. In particular, we investigated the role of heat and mass transfer on catalytic performance. Unexpectedly, we were once again surprised by hBN when various experimental results during these efforts suggested the significance of gas phase chemistry on ODH performance. For example, we observed that upon dilution of hBN with an inert thermal conductor (to mitigate hotspot formation), the observed reactivity scales with total bed volume rather than hBN mass. Up until these studies, we expected all reactivity to stem from oxidized boron species, but these may be only a part of a more complex surface-gas phase reaction network. The final portion of this thesis presents our latest efforts to understand the role of each reactant on surface and gas phase reaction pathways. Within this work, we incorporate water into our reaction feeds to assess its influence as a source of gas phase radical species to carry out propane activation. Indeed, we observe significant rate enhancements by addition of water. This reactivity enhancement likely involves influencing reactive species concentrations primarily in the gas phase and, to a lesser extent, altering the surface composition during ODH. Overall, this thesis expands our understanding of B-based materials as ODH catalysts and highlights the importance of considering gas phase radical chemistry in future process development.

Download or read book Metal Oxides in Heterogeneous Catalysis written by Jacques C. Vedrine and published by Elsevier. This book was released on 2018-01-11 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxides in Heterogeneous Catalysis is an overview of the past, present and future of heterogeneous catalysis using metal oxides catalysts. The book presents the historical, theoretical, and practical aspects of metal oxide-based heterogeneous catalysis. Metal Oxides in Heterogeneous Catalysis deals with fundamental information on heterogeneous catalysis, including reaction mechanisms and kinetics approaches.There is also a focus on the classification of metal oxides used as catalysts, preparation methods and touches on zeolites, mesoporous materials and Metal-organic frameworks (MOFs) in catalysis. It will touch on acid or base-type reactions, selective (partial) and total oxidation reactions, and enzymatic type reactions The book also touches heavily on the biomass applications of metal oxide catalysts and environmentally related/depollution reactions such as COVs elimination, DeNOx, and DeSOx. Finally, the book also deals with future trends and prospects in metal oxide-based heterogeneous catalysis. - Presents case studies in each chapter that provide a focus on the industrial applications - Includes fundamentals, key theories and practical applications of metal oxide-based heterogeneous catalysis in one comprehensive resource - Edited, and contributed, by leading experts who provide perspectives on synthesis, characterization and applications

Download or read book Polyoxomolybdates as Green Catalysts for Aerobic Oxidation written by Anjali Patel and published by Springer. This book was released on 2014-11-22 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneously catalyzed selective oxidations of alcohols is a highly topical field. The first chapter of this brief describes the importance of the selective oxidation of alcohols and advantages of heterogeneous catalysts over conventional catalysts, use of environmentally benign oxidants, and the design of selective catalysts by tailoring of polyoxometalates at the molecular level. Chapter 2 describes synthesis, characterization 11-molybdophosphate based supported materials and their use as heterogeneous catalysts for oxidation of alcohols with molecular oxygen under solvent free mild reaction condition. ZrO2, Al2O3, MCM-41 and zeolite Hβ were used as supports. Chapter 3 describes synthesis, characterization of transition metals (Mn, Co, Ni, Cu)- substituted phosphomolybdates and their use as heterogeneous catalysts for oxidation of alcohols with molecular oxygen under solvent free mild reaction condition. Chapter 4 describes conclusive remarks for present catalytic systems.

Download or read book Design and Development of Quinone Catalysts for Aerobic C N Bond Dehydrogenation Reactions written by and published by . This book was released on 2015 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt: The selective oxidation of organic compounds is a prominent challenge in organic chemistry. Towards this goal, molecular oxygen is an ideal oxidant. Uncatalyzed aerobic oxidation reactions have found important application in the commodity scale synthesis of certain compounds. However, such autoxidation reactions are intrinsically substrate-controlled. More frequently, selective aerobic oxidations are achieved by using a catalyst to promote the desired transformation. Under such a regime the identity of the catalyst -- and therefore the reaction mechanism -- dictates the chemical outcome of the reaction. The development of new catalysts which promote aerobic oxidation reactions is therefore of great significance. This thesis highlights two classes of catalyst that promote selective aerobic oxidation reactions. Chapters 1-4 describe the development of a family of o-quinone catalysts based on o-quinone cofactors found in certain oxidase and dehydrogenase enzymes. Unlike the natural cofactors, which have limited substrate scope, we find evidence for an unnatural reaction pathway that broadens the synthetic utility of these reagents. This family of bioinspired o-quinone catalysts is particularly effective in the aerobic dehydrogenation of C---N bonds. Subsequently, in chapters 5 and 6 I discuss the application of Cu-based catalysts to aerobic oxidation reactions, emphasizing an apparent mechanistic bifurcation between single electron transfer-based mechanisms and organometallic mechanisms within the published literature. Further work describes an application of CuII reagents in the aerobic oxidative cyclization of enamides to oxazoles.

Download or read book The Investigation of Nickel based Catalysts for the Oxidative Dehydrogenation of Ethane written by Justin Lane Park and published by . This book was released on 2019 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The improved rates of ethylene formation observed with these catalysts led to the initial development of a commercially viable nickel based catalyst. The support interactions of NiO with a novel silica doped alumina support show higher yields than previously reported studies of NiO on alumina for ODH. These initial metal support interactions show that the addition of the niobium and ceria to this catalyst should give ethylene yields that are satisfactory for the commercialization of this catalyst.

Download or read book Development and Characterization of Oxyfunctionalized Boron Nitride Catalysts for the Oxidative Dehydrogenation of Light Alkanes to Olefins written by Theodore Agbi and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Light olefins like ethylene and propylene are platform chemicals integral to the chemical industry. Production of polymers, oxygenates, and other important chemical intermediates demand global production volumes that top 100 million metric tons per year. Production of these light olefins, traditionally through steam cracking, is one of the most energy intensive processes in petrochemical sector. Changing refinery feedstocks (i.e. increased availability of natural gas) have created both necessity and opportunity for 'On-Purpose' propylene technologies to meet propylene demands. The oxidative dehydrogenation of propane to propylene (ODHP) is an attractive alternative process to produce propylene. ODHP enables lower process temperatures and avoids coke deactivation of the catalyst, and has the potential to significantly ease energy, capital, and material intensities of industrial propylene production. To-date, metal oxide ODHP catalysts like vanadia-based catalysts-the previous state of the art ODHP catalyst-do not achieve competitive propylene yields to make them industrially viable. The pioneering work of our research group has identified BN-a material renowned for its chemical inertness-as a highly reactive, selective, and stable ODHP catalyst. Since this discovery, we have worked to understand the fundamental reaction mechanisms present and identify structure-performance relationships that may further develop this class of catalyst. To-date, we have developed extensive spectroscopic characterization capabilities to identify the oxyfunctionalized boron layer formed in situ which contains highly dynamic active species responsible for the high reactivity and selectivity observed. Understanding the activation of molecular O2 and functionality of the oxyfunctionalized layer has been a highly collaborative process requiring a myriad of complimentary spectroscopic and reaction studies to develop fundamental insights. As such, I will provide a comprehensive context of our evolving knowledge in this collaborative project that have since been published where possible and will focus mainly on the recent insights made in this work. The work presented in this dissertation characterizes and probes the reactivity of the highly dynamic oxyfunctionalized surface layer that has been correlated with the reactivity and selectivity observed on this catalyst. Herein, the coordination environment of B and extent of oxyfunctionalization were analyzed via X-ray Photoelectron Spectroscopy (XPS), X-ray Absorption Spectroscopy (XAS), and Attenuated Total Reflectance IR (ATR-IR) as a function of the reaction progress. Corresponding reaction studies show direct correlation between the development of tri-coordinated oxygenated B networks and the increasing reactivity and selectivity of the reaction during the catalyst's activation period. The significance of a set of reaction parameters was then examined to identify process levers conducive to oxyfunctionalization quantified by XPS. The acid-base activity of these surface tri-coordnated B networks in the oxyfunctionalized layer are examined via two prototypical reactions: (1) isopropanol decomposition and (2) formic acid decomposition. Catalytic reaction via flow through reactor and temperature programmed decomposition (TPD) studies using Diffuse Reflectance Infrared Fourier Transform IR spectroscopy (DRIFTs) and Mass Spectrometry (MS) are used to extract insights for the adsorption modes of alkoxides and formates their decomposition pathways. Observed surface reactions of isopropoxy intermediates under these conditions are used to understand possible surface reaction pathways available under ODHP conditions. The role of O2 in specific homogeneous pathways of the mixed hetero-homogeneous mechanism previously proposed by us and for supported boron oxide materials are examined. A simplified model for the surface-initiated radical oxidation chemistry pathways, was then used to probe a selectivity descriptor based on the different reactivities of propyl radicals. Using this knowledge, we design, and test model 3D printed BN based monoliths that optimize homogeneous reaction pathways. These catalysts are shown to be highly active and selective and stable for ~2.5wks. The results also suggest that oxygenates may be relevant products from homogeneous reactions. "The Boron Project," as we so lovingly called it, has seen several PhD students matriculate as we contributed diligently to uncovering the behavior of this material. The goal of this work is to highlight new avenues through which we can further understand surface reactivity, new tools through which we can probe gas phase radical chemistries, and new catalyst design approaches.

Download or read book Catalysis written by James J Spivey and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is an increasing challenge for chemical industry and research institutions to find cost-efficient and environmentally sound methods of converting natural resources into fuels chemicals and energy. Catalysts are essential to these processes and the Catalysis Specialist Periodical Report series serves to highlight major developments in this area. This series provides systematic and detailed reviews of topics of interest to scientists and engineers in the catalysis field. The coverage includes all major areas of heterogeneous and homogeneous catalysis and also specific applications of catalysis such as NOx control kinetics and experimental techniques such as microcalorimetry. Each chapter is compiled by recognised experts within their specialist fields and provides a summary of the current literature. This series will be of interest to all those in academia and industry who need an up-to-date critical analysis and summary of catalysis research and applications. Catalysis will be of interest to anyone working in academia and industry that needs an up-to-date critical analysis and summary of catalysis research and applications. Specialist Periodical Reports provide systematic and detailed review coverage in major areas of chemical research. Compiled by teams of leading experts in their specialist fields, this series is designed to help the chemistry community keep current with the latest developments in their field. Each volume in the series is published either annually or biennially and is a superb reference point for researchers. www.rsc.org/spr