Download or read book IR Spectroscopy Based Kinetic Modeling of NH3 SCR on Fe zeolites written by Stavros Skarlis and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selective Catalytic Reduction of nitrogen oxides through urea or ammonia is a well established technique for the efficient abatement of NOx, from mobile diesel engines exhaust stream. Among catalytic formulations proposed, Fe-exchanged zeolites are considered as promising SCR catalysts, due to their enhanced deNOx performance over a broad range of operating temperatures, as well as significant resistance to hydrothermal ageing. In the present work, detailed experimental investigation of the NH3-SCR reactions network over Fe zeolites was performed in order to develop a phenomenological macro-kinetic model oriented to diesel engines aftertreatment system simulation. Dedicated experiments, including IR spectroscopy measurements were performed over lab-synthesized H- and Fe-BEA catalysts in order to unravel mechanistic aspects related to the formation and interactions of ammonia and nitrogen oxides adspecies (namely nitrate and nitrites) on acidic and redox catalytic sites. Formation and decomposition of NH4NO3 was of particular concern. Based on experimental results a multi-site kinetic model was developed, which was able to account for surface acidity variation, interactions of gaseous NH3 and NOx species with iron sites, as well as low temperature physisorption phenomena. The model was successfully validated through simulation of experiments performed over various Fe-zeolite samples, applying a broad range of operating conditions, which showed the interest of the followed approach.
Download or read book Experimental and Kinetic Modeling Studies of Selective Catalytic Reduction of NOx with NH3 on Fe and Cu Zeolite Monolithic Catalysts written by Pranit Subhash Metkar and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The selective catalytic reduction (SCR) of NOx with NH3 is considered to be the most promising technique for the efficient reduction of highly detrimental NOx (to N2) emitted from diesel engine vehicles. Amongst the various catalysts available for SCR, Fe- and Cu-zeolite catalysts are found to be highly stable and efficient towards maximum NOx reduction over a wide temperature range. Cu-zeolites are more active at low temperatures ( 350 oC) while Fe-zeolites are more active at high temperatures ( 400 oC). We carried out a comprehensive experimental and kinetic modeling study of key SCR reactions on Fe- and Cu-zeolite catalysts and present a detailed understanding of mass transfer limitations and kinetics and mechanistic aspects of various SCR reactions on these catalysts. Experiments carried out on monolith catalysts having different washcoat loadings, washcoat thicknesses and lengths indicate the presence of washcoat (or pore) diffusion limitations at intermediate to high temperature range in all the SCR reactions. A detailed analysis of the effect of temperature on the transitions between various controlling regimes (kinetic, washcoat diffusion and external mass transfer) is presented. Agreement in the differential kinetics studies of NO oxidation and standard SCR (NO + O2 + NH3) reactions indicates NO oxidation is the rate determining step for standard SCR. A detailed kinetic model capturing key features of all the SCR reactions is developed. This model accurately predicts the experimentally observed NOx conversions over a wide temperature range and different feed conditions. Finally, a systematic study of various SCR reactions is carried out on a combined system of Fe- and Cu-zeolite monolithic catalysts to determine if a high NOx conversion could be sustained over a wider temperature range than with individual Fe- and Cu-zeolite catalysts. Amongst various configurations, a dual-layer catalyst with a thin Fe-zeolite layer on top of a thick Cu-zeolite layer resulted in a very high NOx removal efficiency over a broad temperature range of practical interest. The kinetic model accurately captures the experimental data with a combined system of Fe- and Cu-zeolite catalysts and provides further insights into the catalyst arrangements for maximum NOx reduction efficiency.
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 Catalysis written by James Spivey and published by Royal Society of Chemistry. This book was released on 2019-03-15 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysts are required for a variety of applications and researchers are increasingly challenged to find cost effective and environmentally benign catalysts to use. This volume looks at modern approaches to catalysis and reviews the extensive literature including direct methane conversion, nanocomposite catalysts for transformation of biofuels into syngas and hydrogen, and catalytic wet air oxidation technology for industrial wastewater treatment. Appealing broadly to researchers in academia and industry, it will be of great benefit to any researcher wanting a succinct reference on developments in this area now and looking to the future.
Download or read book Selective catalytic reduction of NOx with NH3 written by Hanna Sjövall and published by . This book was released on 2009 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 In Situ M ssbauer Spectroscopic Studies of Iron exchanged Y zeolite Catalysts for the Selective Catalytic Reduction with Ammonia and Direct Decomposition of Nitric Oxide written by Ralf Schmidt and published by . This book was released on 1991 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization and Performances of Nanosized Bi metallic Fe based Zeolite Catalysts During Selective Catalytic Reduction SCR of NO by NH3 written by 莎亞達 and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Springer Handbook of Advanced Catalyst Characterization written by Israel E. Wachs and published by Springer Nature. This book was released on 2023-06-12 with total page 1109 pages. Available in PDF, EPUB and Kindle. Book excerpt: Co-edited by world-renowned scientists in the field of catalysis, this book contains the cutting-edge in situ and operando spectroscopy characterization techniques operating under reaction conditions to determine a materials’ bulk, surface, and solution complex and their applications in the field of catalysis with emphasis on solid catalysts in powder form since such catalyst are relevant for industrial applications. The handbook covers from widely-used to cutting-edge techniques. The handbook is written for a broad audience of students and professionals who want to pursue the full capabilities available by the current state-of-the-art in characterization to fully understand how their catalysts really operate and guide the rational design of advanced catalysts. Individuals involved in catalysis research will be interested in this handbook because it contains a catalogue of cutting-edge methods employed in characterization of catalysts. These techniques find wide use in applications such as petroleum refining, chemical manufacture, natural gas conversion, pollution control, transportation, power generation, pharmaceuticals and food processing. fdsfds
Download or read book Environmental Catalysis written by John N. Armor and published by American Chemical Society. This book was released on 1994 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first comprehensive volume on the major aspects of environmental catalysis. Focuses on NO x removal, mobile engine emission controls, power plant emissions, control of volatile organic compounds, SO x emissions, and waste minimization. Overview chapters introduce each section and provide added perspective and coverage. Includes comprehensive technical reports on automotive and diesel emission control catalysis, NO x removal, and removal of chlorinated hydrocarbons from various process streams.
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2726 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics of Heterogeneous Catalytic Reactions written by Michel Boudart and published by Princeton University Press. This book was released on 2014-07-14 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a critical account of the principles of the kinetics of heterogeneous catalytic reactions in the light of recent developments in surface science and catalysis science. Originally published in 1984. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.
Download or read book Verified Synthesis of Zeolitic Materials written by H. Robson and published by Gulf Professional Publishing. This book was released on 2001-06-26 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Zeolite synthesis is an active field of research. As long as this continues, new phases will be discovered and new techniques for preparing existing phases will appear. This edition of Verified Synthesis of Zeolitic Materials contains all the recipes from the first edition plus 24 new recipes. Five new introductory articles have been included plus those from the first edition, some of which have been substantially revised. The XRD patterns have been recorded using different instrument settings from those in the first edition and are intended to conform to typical X-ray diffraction practice. In most cases, only the XRD pattern for the productas synthesised is printed here. The exceptions are those phases which show marked changes in the XRD pattern upon calcination.
Download or read book Modeling and Simulation of Heterogeneous Catalytic Reactions written by Olaf Deutschmann and published by John Wiley & Sons. This book was released on 2013-09-18 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nobel Prize in Chemistry 2007 awarded to Gerhard Ertl for his groundbreaking studies in surface chemistry highlighted the importance of heterogeneous catalysis not only for modern chemical industry but also for environmental protection. Heterogeneous catalysis is seen as one of the key technologies which could solve the challenges associated with the increasing diversification of raw materials and energy sources. It is the decisive step in most chemical industry processes, a major method of reducing pollutant emissions from mobile sources and is present in fuel cells to produce electricity. The increasing power of computers over the last decades has led to modeling and numerical simulation becoming valuable tools in heterogeneous catalysis. This book covers many aspects, from the state-of-the-art in modeling and simulations of heterogeneous catalytic reactions on a molecular level to heterogeneous catalytic reactions from an engineering perspective. This first book on the topic conveys expert knowledge from surface science to both chemists and engineers interested in heterogeneous catalysis. The well-known and international authors comprehensively present many aspects of the wide bridge between surface science and catalytic technologies, including DFT calculations, reaction dynamics on surfaces, Monte Carlo simulations, heterogeneous reaction rates, reactions in porous media, electro-catalytic reactions, technical reactors, and perspectives of chemical and automobile industry on modeling heterogeneous catalysis. The result is a one-stop reference for theoretical and physical chemists, catalysis researchers, materials scientists, chemical engineers, and chemists in industry who would like to broaden their horizon and get a substantial overview on the different aspects of modeling and simulation of heterogeneous catalytic reactions.
Download or read book Pillared Clays and Related Catalysts written by Antonio Gil and published by Springer Science & Business Media. This book was released on 2010-08-28 with total page 531 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the first works introducing the aluminum intercalated clay family in the early 1970s, interest in the synthesis of pillared interlayered clays has increased tremendously, especially research into the properties and applications of new synthesis methods. The need for solids that could be used as cracking catalysts with larger pores than zeolitic materials has spurred the synthesis of new porous materials from clays. Pillared Clays and Related Catalysts reviews the properties and applications of pillared clays and other layered materials used as catalysts, focusing on: the acidity of pillared clays and the effect it has on catalytic performance the use of pillared clays as supports for catalytically active phases, and the use of the resulting solids in environmentally friendly reactions the applications of the selective reduction of NOx the comparison between the reactions of pillared clays and anionic clays.
Download or read book Zeolite Characterization and Catalysis written by Arthur W. Chester and published by Springer Science & Business Media. This book was released on 2009-10-03 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: The idea for putting together a tutorial on zeolites came originally from my co-editor, Eric Derouane, about 5 years ago. I ?rst met Eric in the mid-1980s when he spent 2 years working for Mobil R&D at our then Corporate lab at Princeton, NJ. He was on the senior technical staff with projects in the synthesis and characterization of new materials. At that time, I managed a group at our Paulsboro lab that was responsible for catalyst characterization in support of our catalyst and process development efforts, and also had a substantial group working on new material synthesis. Hence, our interests overlapped considerably and we met regularly. After Eric moved back to Namur (initially), we maintained contact, and in the 1990s, we met a number of times in Europe on projects of joint interest. It was after I retired from ExxonMobil in 2002 that we began to discuss the tutorial concept seriously. Eric had (semi-)retired and lived on the Algarve, the southern coast of Portugal. In January 2003, my wife and I spent 3 weeks outside of Lagos, and I worked parts of most days with Eric on the proposed content of the book. We decided on a comprehensive approach that ultimately amounted to some 20+ chapters covering all of zeolite chemistry and catalysis and gave it the title Zeolite Chemistry and Catalysis: An integrated Approach and Tutorial.
Download or read book Chemisorption and Reactivity on Supported Clusters and Thin Films written by R.M. Lambert and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneous catalysis provides the backbone of the world's chemical and oil industries. The innate complexity of practical catalytic systems suggests that useful progress should be achievable by investigating key aspects of catalysis by experimental studies on idealised model systems. Thin films and supported clusters are two promising types of model system that can be used for this purpose, since they mimic important aspects of the properties of practical dispersed catalysts. Similarly, appropriate theoretical studies of chemisorption and surface reaction clusters or extended slab systems can provide valuable information on the factors that underlie bonding and catalytic activity. This volume describes such experimental and theoretical approaches to the surface chemistry and catalytic behaviour of metals, metal oxides and metal/metal oxide systems. An introduction to the principles and main themes of heterogeneous catalysis is followed by detailed accounts of the application of modern experimental and theoretical techniques to fundamental problems. The application of advanced experimental methods is complemented by a full description of theoretical procedures, including Hartree-Fock, density functional and similar techniques. The relative merits of the various approaches are considered and directions for future progress are indicated.
