Download or read book An Experimental Investigation of the Urea water Decomposition and Selective Catalytic Reduction SCR of Nitric Oxides with Urea Using V2O5 WO3 TiO2 Catalyst written by Jasmeet Singh Johar and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two flow reactor studies, using an electrically heated laminar flow reactor over Vanadia based (V2O5-WO3/TiO2) honeycomb catalyst, were performed at 1 atm pressure and various temperatures. The experiments were conducted using simulated exhaust gas compositions for different exhaust gases. A quartz tube was used in order to establish inert conditions inside the reactor. The experiments utilized a Fourier transform infrared (FTIR) spectrometer in order to perform both qualitative and quantitative analysis of the reaction products. Urea-water solution decomposition was investigated over V2O5-WO3/TiO2 catalyst over the entire SCR temperature range using the temperature controlled flow reactor. The solution was preheated and then injected into pure nitrogen (N2) stream. The decomposition experiments were conducted with a number of oxygen (O2) compositions (0,1, 10, and 15%) over the temperature range of 227°C to 477°C. The study showed ammonia (NH3), carbon-dioxide (CO2) and nitric oxide (NO) as the major products of decomposition along with other products such as nitrous oxide (N2O) and nitrogen dioxide(NO2). The selective catalytic reduction (SCR) of nitric oxide (NO) with urea-water solution over V2O5-WO3/TiO2 catalyst using a laboratory laminar-flow reactor was investigated. Urea-water solution was injected at a temperature higher than the vaporization temperature of water and the flow reactor temperature was varied from 127°C to 477°C. A FTIR spectrometer was used to determine the concentrations of the product species. The major products of SCR reduction were NH3, NO and CO2 along with the presenceof other minor products NO2 and N2O. NO removal of up to 87% was observed. The aim of the urea-water decomposition experiments was to study the decomposition process as close to the SCR configuration as possible. The aim of the SCR experiments was to delineate the effect of various parameters including reaction temperature and O2 concentration on the reduction process. The SCR investigation showed that changing parameter values significantly affected the NO removal, the residual NH3 concentration, the temperature of the maximum NO reduction, and the temperature of complete NH3 conversion. In the presence of O2, the reaction temperature for maximum NO reduction was 377°C for [Beta] ratio of 1.0.

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 NO_x" that was published in Catalysts

Download or read book An Investigation of Urea Decomposition and Selective Non catalytic Removal of Nitric Oxide with Urea written by Yong Hun Park and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of urea (NH2CONH2) to remove nitric oxide (NO) from exhaust streams was investigated using a laboratory laminar-flow reactor. The experiments used a number of gas compositions to simulate different combustion exhaust gases. The urea was injected into the gases as a urea-water solution. The decomposition processes of the urea-water solutions and urea powder were examined. For both the nitric oxide removal and the urea decomposition experiments, a Fourier transform infrared (FTIR) spectrometer was used to determine the concentrations of the product species. The products from the decomposition were examined every 50 K from 500 K to 800 K. The dominant products were ammonia (NH3), isocyanuric acid (HNCO) and carbon dioxide (CO2). In case of urea-water solution decomposition, for gas temperatures between 550 and 650 K, the highest concentrations were for NH3 and HNCO. On the other hand, the concentrations of CO2 were highest for gas temperatures of about 500 - 550 K. For temperatures above about 650 K, the amount of these three dominant prod-ucts slightly decreased as temperature increased. For the nitric oxide removal (SNCR) experiments, the gas mixture was heated to temperatures between 800 K and 1350 K. Depending on the temperature, gas composition, residence time, and urea feed rate, removal levels of up to 95% were obtained. Other by-products such as N2O were detected and quantified. The effects of the urea/NO (beta) ratio were determined by varying the urea concentration for a constant NO con-centration of 330 ppm. The effects of the levels of oxygen (O2) in the exhaust gases and the residence time also were investigated. Increasing the urea/NO ratio and residence time resulted in higher NO removal and increased the temperature window of the nitric oxide removal.

Download or read book Selective Catalytic Reduction SCR of Nitric Oxide NO with Ammonia Over Vanadia based and Pillared Interlayer Clay based Catalysts written by Hyuk Jin Oh and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The selective catalytic reduction (SCR) of nitric oxide (NO) with ammonia over vanadia-based (V2O5-WO3/TiO2) and pillared interlayer clay-based (V2O5/Ti-PILC) monolithic honeycomb catalysts using a laboratory laminar-flow reactor was investigated. The experiments used a number of gas compositions to simulate different combustion gases. A Fourier transform infrared (FTIR) spectrometer was used to determine the concentrations of the product species. The major products were nitric oxide (NO), ammonia (NH3), nitrous oxide (N2O), and nitrogen dioxide (NO2). The aim was to delineate the effect of various parameters including reaction temperature, oxygen concentration, NH3-to-NO ratio, space velocity, heating area, catalyst arrangement, and vanadium coating on the removal of nitric oxide. The investigation showed that the change of the parameters significantly affected the removals of NO and NH3 species, the residual NH3 concentration (or NH3 slip), the temperature of the maximum NO reduction, and the temperature of complete NH3 conversion. The reaction temperature was increased from the ambient temperature (25°C) to 450°C. For both catalysts, high NO and NH3 removals were obtained in the presence of a small amount of oxygen, but no significant influence was observed from 0.1 to 3.0% O2. An increase in NH3-to-NO ratio increased NO reduction but decreased NH3 conversions. For V2O5-WO3/TiO2, the decrease of space velocity increased NO and NH3 removals and broadened the active temperature window (based on NO> 88% and NH3> 87%) about 50°C. An increase in heating area decreased the reaction temperature of the maximum NO reduction from 350 to 300 ʻC, and caused the active reaction temperature window (between 250 and 400 ʻC) to shift toward 50 ʻC lower reaction temperatures (between 200 and 350°C). The change of catalyst arrangements resulted slight improvement for NO and NH3 removals, therefore, the change might contribute to more gas removals. The catalyst with extra vanadium coating showed higher NO reductions and NH3 conversions than the catalyst without the extra vanadium coating.

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 Experimental Investigation of a Dual catalyst for the Selective Catalytic Reduction of Nitric Oxide with Ammonia written by Frank G. Medros and published by . This book was released on 1987 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetic Modeling of Selective Non catalytic Reduction Sncr of Nitric Oxide Using Urea water Solution written by Rajasree Retnamma and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Superior Catalysts for Selective Catalytic Reduction of Nitric Oxide Annual Technical Report September 30 1993 September 29 1994 written by and published by . This book was released on 1995 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: A delaminated Fe2O3-pillared clay catalyst was prepared for the selective catalytic reduction (SCR) of NO by NH3 at above 300°C. The delaminated pillard clay was characterized by ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectroscopy) chemical analysis, XRD (X-ray diffraction) structure and line broadening analyses, micropore size probing, and Moessbauer analysis. These analyses showed that the catalyst contained fragmented Fe2O3-pillared clay forming {open_quotes}house-of-cards{close_quotes} structure with dispersed Fe2O3 particles approximately 170 Å in size. The SCR activity of the delaminated pillard clay was higher than the commercial-type V2O5 + WO3/TiO2 catalyst, and also higher than the undelaminated pillard clay and supported Fe2O3 catalysts, under conditions with SO2. Infrared measurements of adsorbed NH3 showed strong Bronsted acidity which was caused possibly by interactions between Fe2O3 and clay.

Download or read book Superior Catalysts for Selective Catalytic Reduction of Nitric Oxide Quarterly Technical Progress Report 1 January 1994 31 March 1994 written by and published by . This book was released on 1994 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past quarter, progress has been made in four tasks as summarized below: Task 1: A delaminated Fe2O3 pillared clay was synthesized and carefully characterized. The chemical composition was measured by ICP atomic emission spectrometry. The structural changes in the clay as well as the iron oxide particle sizes were characterized by X-ray diffraction techniques. Task 2: The Selective Catalytic Reduction (SCR, i.e., NO reduction with NH3) activities of the delaminated pillared clay were tested and compared with four other most active SCR catalysts: a commercial V2O5 + WO3/TiO2 catalyst, a Fe2O3-pillared clay, and two supported Fe2O3 catalysts (on Al2O3 and TiO2). The delaminated Fe2O3 pillared clay exhibited the highest SCR activities. Catalyst stability test showed that the delaminated sample was also stable. Task 3: To further increase the SCR activity of the delaminated pillared clay, Cr2O3 was doped as a promoter by incipient wetness. Task 4: Deactivation effects of SO2 and H2O on the SCR activities of the delaminated Fe2O3 pillared clay were studied, and compared with other SCR catalysts. The delaminated clay catalyst showed the least deactivation.

Download or read book Superior Catalysts for Selective Catalytic Reduction of Nitric Oxide Final Technical Report October 1 1993 September 30 1995 written by and published by . This book was released on 1995 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most advanced and proven technology for NO(subscript x) control for stationary sources is Selective Catalytic Reduction (SCR). In SCR, NO(subscript x) is reduced by NH3 to N2 and H2O. The commercial catalysts are based on V2O5/TiO2, and the vanadium-based catalysts are patented by the Japanese (Mitsubishi). However, there are three main advantages for the vanadium-based SCR catalyst: (a) a tendency to be poisoned in the flue gas; (b) oxidation of SO2 to SO3 by V2O5, this is a particularly severe problem due to the higher sulfur content of American coals compared with coals used in Japan (from Australia) and in Europe; (c) environmental problems involved in the disposal of the spent catalyst (due to the toxicity of vanadium). In order to overcome these problems, in addition to the undesirable dominance by the Japanese patent position, the authors have studied in this project a new type of catalyst for the SCR reaction; namely, pillared clays, which have adjustable, unique structures and acidity. Three types of catalysts were developed and tested for this reaction, i.e. Fe2O3-pillared clays, delaminated Fe2O3-pillared clays, and ion-exchanged pillared clays. The project was divided into sixteen tasks, and will be reported as such.

Download or read book Selective Catalytic Reductions of Nitric Oxide with Ammonia and Urea Over Copper and Iron based Catalysts written by Julie A. Doherty and published by . This book was released on 2004 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Ausschreiben des K niglichen Landes Consistoriums vom 13 Juli 1883 written by and published by . This book was released on 1883 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetics of Chemical Reactions written by Guy B. Marin and published by John Wiley & Sons. This book was released on 2019-04-29 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second, extended and updated edition presents the current state of kinetics of chemical reactions, combining basic knowledge with results recently obtained at the frontier of science. Special attention is paid to the problem of the chemical reaction complexity with theoretical and methodological concepts illustrated throughout by numerous examples taken from heterogeneous catalysis combustion and enzyme processes. Of great interest to graduate students in both chemistry and chemical engineering.

Download or read book Selective Catalytic Reduction SCR of Nitric Oxide with Ammonia Using Cu ZSM 5 and Va based Honeycomb Monolith Catalysts written by Saurabh Gupta and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, the steady-state performance of zeolite-based (Cu-ZSM-5) and vanadium-based honeycomb monolith catalysts was investigated in the selective catalytic reduction process (SCR) for NO removal using NH3. The aim was to delineate the effect of various parameters including pretreatment of the catalyst sample with H2, NH3-to-NO ratio, inlet oxygen concentration, and space velocity. The concentrations of the species (e.g. NO, NH3, and others) were determined using a Fourier Transform Infrared (FTIR) spectrometer. The temperature was varied from ambient (25 C) to 500 C. The investigation showed that all of the above parameters (except pre-treatment with H2) significantly affected the peak NO reduction, the temperature at which peak NO reduction occurred, and residual ammonia left at higher temperatures (also known as 'NH3 slip'). Depending upon the particular values of the parameters, a peak NO reduction of around 90% was obtained for both the catalysts. However, an accompanied generation of N2O and NO2 species was observed as well, being much higher for the vanadium-based catalyst than for the Cu-ZSM-5 catalyst. For both catalysts, the peak NO reduction decreased with an increase in space velocity, and did not change significantly with an increase in oxygen concentration. The temperatures at which peak NO reduction and complete NH3 removal occurred increased with an increase in space velocity but decreased with an increase in oxygen concentration. The presence of more ammonia at the inlet (i.e. higher NH3-to-NO ratio) improved the peak NO reduction but simultaneously resulted in an increase in residual ammonia. Pretreatment of the catalyst sample with H2 (performed only for the Cu-ZSM-5 catalyst) did not produce any perceivable difference in any of the results for the conditions of these experiments.

Download or read book Design and Development of Heavy Duty Diesel Engines written by P. A. Lakshminarayanan and published by Springer Nature. This book was released on 2019-11-05 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended to serve as a comprehensive reference on the design and development of diesel engines. It talks about combustion and gas exchange processes with important references to emissions and fuel consumption and descriptions of the design of various parts of an engine, its coolants and lubricants, and emission control and optimization techniques. Some of the topics covered are turbocharging and supercharging, noise and vibrational control, emission and combustion control, and the future of heavy duty diesel engines. This volume will be of interest to researchers and professionals working in this area.

Download or read book Selective Catalytic Reduction of Nitric Oxide by Ammonia Over Iron Exchanged Y Zeolites written by Michael Dimitrios Amiridis and published by . This book was released on 1991 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt: