Download or read book New Heterogeneous Catalysts for the Selective Reduction of NOx Under Lean Conditions Final Report written by and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The original goal of this program was the identification and design of new noble-metal-based catalysts for the selective catalytic reduction of nitric oxide by hydrocarbons under excess oxygen (i.e., ''lean'') conditions (HC-SCR). Work conducted in the first funding cycle of this award (i.e., 1997-2000) was successful in allowing us to develop an understanding of the fundamental surface chemistry taking place during the adsorption and reaction of nitrogen oxides and propylene on the surface of supported noble metal catalysts. Both experimental results collected in our own group as well as molecular simulation results published by Professor Neurock suggested that in order to improve the performance of the Pt catalysts--in terms of the nitrogen selectivity and the temperature window of operation-- it was necessary to introduce a second metal. However, synthesizing such catalysts with the metals of interest (i.e., Pt-Au, Pt-Ru, Pt-Rh, etc.) with some degree of control of the structure and composition of the resulting supported metal particles is in itself a research challenge. Consequently, the bulk of our efforts during the second funding cycle of this award (covered by this report) was shifted to the use of organometallic cluster precursors for the synthesis on novel bimetallic catalysts. During this time we have also continued to maintain an interest in NOx abatement, but have redirected our efforts from the HC-SCR process to the more promising from a commercial standpoint NOx Storage Reduction (NSR) approach.
Download or read book Plasma Assisted Heterogeneous Catalysis for NOx Reduction in Lean Burn Engine Exhaust written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent developments in catalytic control of NOx are revealing the significance of NO2 as an intermediary for achieving higher NOx removal efficiencies. This paper discusses the combination of the plasma with a catalyst to improve the selective reduction of NOx under lean-burn conditions. It is shown that the main effect of the plasma is to enhance the gas-phase oxidation of NO to NO2. The reduction of NOx to N2 is then accomplished by the heterogeneous reaction of NO2 with activated hydrocarbons on the catalyst surface. By using a plasma, one can take advantage of a new class of catalysts that are potentially more durable, more active, more selective and more sulfur-tolerant compared to conventional lean-NOx catalysts. The plasma-assisted catalytic reduction process can be implemented with any type of plasma reactor and does not require a specific type of electrical power supply. It can also easily accommodate any type of catalyst support structure.
Download or read book Catalytic Reduction of NOx Under Lean Conditions written by and published by . This book was released on 1997 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heterogeneous Catalysts for Clean Technology written by Karen Wilson and published by John Wiley & Sons. This book was released on 2013-09-17 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reactive, but not a reactant. Heterogeneous catalysts play an unseen role in many of today's processes and products. With the increasing emphasis on sustainability in both products and processes, this handbook is the first to combine the hot topics of heterogeneous catalysis and clean technology. It focuses on the development of heterogeneous catalysts for use in clean chemical synthesis, dealing with how modern spectroscopic techniques can aid the design of catalysts for use in liquid phase reactions, their application in industrially important chemistries - including selective oxidation, hydrogenation, solid acid- and base-catalyzed processes - as well as the role of process intensification and use of renewable resources in improving the sustainability of chemical processes. With its emphasis on applications, this book is of high interest to those working in the industry.
Download or read book The Selective Catalytic Reduction of NOx by CH b3 sOH Under Oxidising Conditions Over Al b2 sO b3 s Based Catalysts written by Eibhlin Halpin and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Platinum Dispersion and Catalyst Architecture for Lean NOx Reduction written by Bijesh Man Shakya and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The combination of NOx storage and reduction (NSR) and selective catalytic reduction (SCR) catalyst is a promising technology for the reduction of NOx emission from the exhaust of lean-burn or diesel engine vehicles. In the combined NSR/SCR system, NH3 generated in LNT during the rich phase is utilized in the SCR for additional NOx conversion. Therefore, the performance of the combined NSR/SCR depends strongly on the NH3 generating function of the NSR catalyst. Earlier studies show that lower Pt dispersion NSR catalysts give higher selectivity to NH3 making them ideal candidates for this particular application. In the first part of the work, we performed experiments on lower Pt dispersion catalysts to gain insights on the mechanistic effects of Pt dispersion on NOx conversion and selectivity. We also developed an improved crystallite-scale model of NSR that explicitly accounts for the crystallite scale gradients of the stored NOx. The calibrated model is able to capture the effects of Pt dispersion, rich phase duration and overall cycle time on cycle-averaged conversion and selectivity trends. In the second part, we carried out a simulation study of dual-layer NSR+SCR monolithic catalyst using (1+1)-D model of catalytic monolith with individually-calibrated global kinetic models. Simulations show that multiple combinations of catalyst loading can attain a given NOx conversion and N2 selectivity, and that there exists a loading of SCR washcoat for a given NSR catalyst for which the NOx conversion is maximum. Simulations of the dual-brick monolith are also performed to analyze the effects of catalyst architecture. Under identical conditions, the simulations show that dual-layer catalyst outperforms the dual-brick largely because of the better utilization of generated NH3. Finally, we performed an optimization study to identify optimal loading and configuration of combined Fe+Cu zeolite catalyst that gives overall high NOx removal efficiency over a broad range of temperature. Simulations suggest that the brick configuration in which Fe- brick is followed by Cu- catalyst is slightly better than dual-layer in which Fe- is coated on top of Cu- architecture. This is attributed to the diffusional limitations in the washcoat that is more pronounced in the dual-layer catalysts.
Download or read book New Concepts in Selective Oxidation Over Heterogeneous Catalysts written by Gabriele Centi and published by . This book was released on 1998 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Catalytic Reduction of NOx written by Oliver Kröcher and published by MDPI. This book was released on 2018-12-14 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Selective Catalytic Reduction of NOx" that was published in Catalysts
Download or read book NOx Trap Catalysts and Technologies written by Luca Lietti and published by Royal Society of Chemistry. This book was released on 2018-06-13 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will be the first to comprehensively present the current research on catalysts used for NOx abatement in lean exhausts.
Download or read book Handbook of Climate Change Mitigation written by Wei-Yin Chen and published by Springer. This book was released on 2012-02-13 with total page 2130 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a mounting consensus that human behavior is changing the global climate and its consequence could be catastrophic. Reducing the 24 billion metric tons of carbon dioxide emissions from stationary and mobile sources is a gigantic task involving both technological challenges and monumental financial and societal costs. The pursuit of sustainable energy resources, environment, and economy has become a complex issue of global scale that affects the daily life of every citizen of the world. The present mitigation activities range from energy conservation, carbon-neutral energy conversions, carbon advanced combustion process that produce no greenhouse gases and that enable carbon capture and sequestion, to other advanced technologies. From its causes and impacts to its solutions, the issues surrounding climate change involve multidisciplinary science and technology. This handbook will provide a single source of this information. The book will be divided into the following sections: Scientific Evidence of Climate Change and Societal Issues, Impacts of Climate Change, Energy Conservation, Alternative Energies, Advanced Combustion, Advanced Technologies, and Education and Outreach.
Download or read book Chemical Abstracts written by and published by . This book was released on 1994-03-07 with total page 1668 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Chemistry of Pincer Compounds written by David Morales-Morales and published by Elsevier. This book was released on 2011-08-11 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pincer complexes are formed by the binding of a chemical structure to a metal atom with at least one carbon-metal bond. Usually the metal atom has three bonds to a chemical backbone, enclosing the atom like a pincer. The resulting structure protects the metal atom and gives it unique properties.The last decade has witnessed the continuous growth in the development of pincer complexes. These species have passed from being curiosity compounds to chemical chameleons able to perform a wide variety of applications. Their unique metal bound structures provide some of the most active catalysts yet known for organic transformations involving the activation of bonds. The Chemistry of Pincer Compounds details use of pincer compounds including homogeneous catalysis, enantioselective organic transformations, the activation of strong bonds, the biological importance of pincer compounds as potential therapeutic or pharmaceutical agents, dendrimeric and supported materials. * Describes the chemistry and applications of this important class of organometallic and coordination compounds* Covers the areas in which pincer complexes have had an impact* Includes information on more recent and interesting pincer compounds not just those that are well-known
Download or read book Comprehensive Inorganic Chemistry II written by and published by Newnes. This book was released on 2013-07-23 with total page 7694 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Inorganic Chemistry II, Nine Volume Set reviews and examines topics of relevance to today’s inorganic chemists. Covering more interdisciplinary and high impact areas, Comprehensive Inorganic Chemistry II includes biological inorganic chemistry, solid state chemistry, materials chemistry, and nanoscience. The work is designed to follow on, with a different viewpoint and format, from our 1973 work, Comprehensive Inorganic Chemistry, edited by Bailar, Emeléus, Nyholm, and Trotman-Dickenson, which has received over 2,000 citations. The new work will also complement other recent Elsevier works in this area, Comprehensive Coordination Chemistry and Comprehensive Organometallic Chemistry, to form a trio of works covering the whole of modern inorganic chemistry. Chapters are designed to provide a valuable, long-standing scientific resource for both advanced students new to an area and researchers who need further background or answers to a particular problem on the elements, their compounds, or applications. Chapters are written by teams of leading experts, under the guidance of the Volume Editors and the Editors-in-Chief. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. The chapters will not provide basic data on the elements, which is available from many sources (and the original work), but instead concentrate on applications of the elements and their compounds. Provides a comprehensive review which serves to put many advances in perspective and allows the reader to make connections to related fields, such as: biological inorganic chemistry, materials chemistry, solid state chemistry and nanoscience Inorganic chemistry is rapidly developing, which brings about the need for a reference resource such as this that summarise recent developments and simultaneously provide background information Forms the new definitive source for researchers interested in elements and their applications; completely replacing the highly cited first edition, which published in 1973
Download or read book Urea SCR Technology for deNOx After Treatment of Diesel Exhausts written by Isabella Nova and published by Springer Science & Business Media. This book was released on 2014-03-14 with total page 715 pages. Available in PDF, EPUB and Kindle. Book excerpt: Urea-SCR Technology for deNOx After Treatment of Diesel Exhausts presents a complete overview of the selective catalytic reduction of NOx by ammonia/urea. The book starts with an illustration of the technology in the framework of the current context (legislation, market, system configurations), covers the fundamental aspects of the SCR process (catalysts, chemistry, mechanism, kinetics) and analyzes its application to useful topics such as modeling of full scale monolith catalysts, control aspects, ammonia injections systems and integration with other devices for combined removal of pollutants.
Download or read book Design of Heterogeneous Catalysts written by Umit S. Ozkan and published by John Wiley & Sons. This book was released on 2009-02-11 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-awaited reference source is the first book to focus on this important and hot topic. As such, it provides examples from a wide array of fields where catalyst design has been based on new insights and understanding, presenting such modern and important topics as self-assembly, nature-inspired catalysis, nano-scale architecture of surfaces and theoretical methods. With its inclusion of all the useful and powerful tools for the rational design of catalysts, this is a true "must have" book for every researcher in the field.
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.
