Download or read book Oxydation du m thane basse temp rature sur des catalyseurs base de m taux pr cieux written by Laetitia Urfels and published by . This book was released on 2003 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette étude concerne l'oxydation totale du méthane à basse température sur des catalyseurs à base de Pd et/ou de Pt. L'application visée est l'épuration des échappements des moteurs fonctionnant au gaz naturel et en mélange pauvre. La problématique est que l'eau et les composés soufrés présents dans les effluents, sont susceptibles de limiter l'activité des catalyseurs utilisés. Les catalyseurs Pd/Al2O3 et Pt/Al2O3 ont été retenus comme systèmes de référence dans la réaction considérée. En absence et en présence d'eau dans le mélange réactionnel, le catalyseur Pd/Al2O3 est le plus actif. Il est, en revanche, très sensible à H2S et ne se régénère que partiellement sous oxygène à des températures de 650ʿC. Le catalyseur Pt/Al2O3 est moins sensible au soufre et se régénère quasi totalement sous O2 à 500ʿC. Afin d'obtenir des catalyseurs plus actifs en oxydation du méthane et offrant une meilleure résistance à l'eau et au soufre que les solides de référence, des systèmes à base de Pt et Pd déposés sur des supports à propriétés redox (SnO2 et Ce0,67Zr0,33O2) ont été préparés. Ces supports ne permettent une amélioration des performances catalytiques en absence et en présence d'eau que dans le cas du platine. Les catalyseurs Pt/SnO2 et Pt/Ce0,67Zr0,33O2 perdent, cependant, la majeure partie de leur activité en présence de H2S. Enfin, une étude a débuté sur des catalyseurs bimétalliques PdxPt1-x/Al2O3. Ils sont, en l'absence d'eau et de poison soufré, plus actifs que le solide Pd/Al2O3 pour x 0,65.
Download or read book Oxydation du m thane dans les effluents de moteurs gaz fonctionnant en m lange pauvre sur des catalyseurs base de m taux pr cieux written by Grégory Lapisardi and published by . This book was released on 2007 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le présent travail concerne l’étude de catalyseurs à base de Pt et de Pd pour l’oxydation totale du méthane en vue de son élimination des effluents de moteurs à gaz fonctionnant en mélange pauvre (GNV, cogénération). Des catalyseurs monométalliques de Pd et de Pt et bimétalliques PdxPt1-x ont été déposés sur Al2O3 et SnO2 et étudiés. L’influence d’un vieillissement sous atmosphère humide permettant de simuler un fonctionnement de longue durée a été examinée. Les catalyseurs bimétalliques déposés sur Al2O3 et riches en Pd se révèlent plus performants que le catalyseur référence Pd/Al2O3 : meilleure résistance au vieillissement, meilleure activité en atmosphère humide. Ces propriétés sont reliées à une interaction de Pt avec Pd, interaction révélée par différentes techniques physico-chimiques. L’utilisation de SnO2 comme support ne permet pas d’améliorer les performances catalytiques des catalyseurs mono ou bimétalliques. Tous les catalyseurs étudiés se désactivent en présence de poisons soufrés (H2S, SO2) par empoisonnement des sites actifs. La stabilité des espèces poisons dépend du métal, du support utilisé et de la température de réaction
Download or read book Oxydation du m thane basse et haute temp rature application de proc d s plasma et ou catalyse written by Alexandre Baylet and published by . This book was released on 2008 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research work deals with CH4 oxidation coming from road transport, CH4 being a well-known greenhouse gas, with CH4 removal from exhaust gas of Diesel engine. Total CH4 oxidation has been studied : - At low temperature by Plasma/Catalysis process : from all the systems tested, the combination of a coaxial DBD non-thermal plasma combined with Pd/Al2O3 catalyst in POST-plasma position allows to convert 30 % of CH4 with an energy of 225 J.L-1 (Q=600 mL.min-1, N2/O2/CO2/H2O/0.5%CH4, T=250 °C, H=150 mm) while minimising O3 production and avoiding NOx production. However, the power consumed (> kW) is too significant for prospective vehicle applications. - At low temperature on Pd/Al2O3 catalysts (light-off temperature) : the re-oxidation step of Pd° is faster on small particles but CH4 activation is more difficult due to stabilization of small PdO particles by the support. A series of reductant pulses (CH4 or C3H6) in isothermal conditions allows to activate the catalyst and to reach a maximum of conversion. - At high temperature on Pd/(modified oxide) catalysts (peak at high temperature) : (La, Sr, Ba, Mn) doped alumina preparation with a specific surface area of 50 m2.g-1 allows to reach 90 % of CH4 conversion at 700 °C and to maintain an excellent thermal stability. A Mars and van-Krevelen mechanism, with oxygen transfer from support to palladium particles is proposed in order to explain catalytic activity and thermal stability differences in comparison to the Pd/Al2O3 reference catalyst.
Download or read book Catalyseurs base de m taux nobles pour l oxydation totale du m thane written by Delphine Roth and published by . This book was released on 2000 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book OXYDATION ET ACTIVATION DU METHANE SUR DES CATALYSEURS D OXYDES DE METAUX DE TRANSITION ET DE TERRES RARES IRRADIES PAR MICROONDE written by MINA.. SOUIRI OUSALAH and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: DANS CE TRAVAIL, ON COMPARE LES REACTIONS D'OXYDATION ET D'ACTIVATION DU METHANE EFFECTUEES SUR DES CATALYSEURS OXYDES DE METAUX DE TRANSITION ET DE TERRES-RARES LORSQU'ILS SONT IRRADIES PAR MICROONDE ET CHAUFFES DANS UN FOUR CLASSIQUE. L'INSTALLATION MICROONDE UTILISEE PERMET D'OBTENIR UN CHAMP ELECTROMAGNETIQUE INTENSE ET HOMOGENE CAPABLE DE CHAUFFER DES CATALYSEURS AYANT DES PERTES DIELECTRIQUES FAIBLES. POUR LES CATALYSEURS D'OXYDATION DE STRUCTURE PEROVSKITES: LACO#3, SMCOO#3 ET LANIO#0#,#5 FE0#,#5O#3 LES QUANTITES DE PRODUIS FORMES EN MICROONDE SONT IDENTIQUES A CELLES OBTENUES DANS LE CAS D'UN CHAUFFAGE CLASSIQUE. L'ACTION DU CHAMP ELECTROMAGNETIQUE SUR CES CATALYSEURS S'EXPLIQUE PAR UN SIMPLE CHAUFFAGE DES CATALYSEURS. DE MEME, POUR LES CATALYSEURS D'ACTIVATION DU METHANE LA#2O#3 ET LA#2ZR#2O#3 L'ACTIVATION DU CHAMP ELECTROMAGNETIQUE NE SE DISTINGUE PAS D'UN SIMPLE CHAUFFAGE. PAR CONTRE, POUR LES CATALYSEURS D'ACTIVATION DU METHANE A SAVOIR: SMLIO#2, (SMLIO#2)#0#,#8(CAO-MGO)#0#,#2 ET (LALIO#2)#0#,#6#7(SRO-MGO)#0#,#3#3, LE CHAMP ELECTROMAGNETIQUE A POUR EFFET D'AUGMENTER LA SELECTIVITE ET LE RENDEMENT DES PRODUITS ETHANE ET ETHYLENE. L'ENSEMBLE DES RESULTATS S'INTERPRETE EN SUPPOSANT QUE LE CHAMP ELECTROMAGNETIQUE AGIT EN EXCITANT SELECTIVEMENT CERTAINES ATOMES D'OXYGENES DONT LA MOBILITE ELECTRIQUE EST ACCRUE PAR LA DEFORMATION DU CRISTAL DUE AU DOPAGE. PAR AILLEURS, IL FAUT NOTER QUE LE CATALYSEUR EST PORTE A UNE TEMPERATURE SUPERIEURE DE CELLE DE LA PHASE GAZEUSE LORSQUE LE CATALYSEUR EST IRRADIE PAR UN CHAMP ELECTROMAGNETIQUE. CECI LIMITE LES REACTIONS SECONDAIRES QUI CONDUISENT A LA FORMATION DE MONOXYDE ET DE DIOXYDE DE CARBONE ET QUI ONT LIEU EN GENERAL DANS LA PHASE GAZEUSE
Download or read book Oxydation m nag e du m thane en formald hyde sur des catalyseurs base d oxyde de vanadium support sur silice m soporeuse written by Dinh Lam Nguyen and published by . This book was released on 2003 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce travail de thèse correspond à la mise au point d'un catalyseur performant pour l'oxydation ménagée du méthane en formaldéhyde par oxygène à pression atmosphérique et à une température inférieure à 600°C. Ceci a nécessité l'élaboration d'une nouvelle méthode de synthèse d'un catalyseur de type vanadium supporté sur silice mésoporeuse basée sur la co-condensation d'espèces silicium et vandium monomérique (VO2(Oh)2-) dans une solution contenant un surfactant. Différentes techniques (DRX, BET et adsorption isotherme, MEB, Raman, Ir, TRP, RPE...) ont été utilisées pour caractériser la structure du catalyseur et la nature des expèces vanadium ainsi que leur isolation. Des études cinétiques et spectroscopiques ont été mises en oeuvre pour comprendre le mécanisme réactionnel et déterminer la nature des expèces adsorbées
Download or read book Graphene written by Wonbong Choi and published by CRC Press. This book was released on 2016-04-19 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the late 20th century, graphene-a one-atom-thick planar sheet of sp2-bonded carbon atoms densely packed in a honeycomb crystal lattice-has garnered appreciable attention as a potential next-generation electronic material due to its exceptional properties. These properties include high current density, ballistic transport, chemical inertness,
Download or read book A German English Dictionary for Chemists written by Austin M 1876-1956 Patterson and published by Scholar Select. This book was released on 2015-08-08 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book Faecal Sludge Management written by Linda Strande and published by IWA Publishing. This book was released on 2014-08-15 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.
Download or read book Frontline and Factory written by Roy MacLeod and published by Springer Science & Business Media. This book was released on 2007-05-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents a first considered attempt to study the factors that conditioned industrial chemistry for war in 1914-18. Taking a comparative perspective, it reflects on the experience of France, Germany, Austria, Russia, Britain, Italy and Russia, and points to significant similarities and differences. It looks at changing patterns in the organisation of industry, and at the emerging symbiosis between science, industry and the military.
Download or read book Food Chemistry Research Developments written by Konstantinos N. Papadopoulos and published by Nova Publishers. This book was released on 2008 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods. The biological substances include such items as meat, poultry, lettuce, beer, and milk as examples. It is similar to biochemistry in its main components such as carbohydrates, lipids, and protein, but it also includes areas such as water, vitamins, minerals, enzymes, food additives, flavours, and colours. This discipline also encompasses how products change under certain food processing techniques and ways either to enhance or to prevent them from happening. An example of enhancing a process would be to encourage fermentation of dairy products with lactic acid; an example of a preventing process would be stopping the Maillard reaction on the surface of freshly cut Red Delicious apples whether by hand or mechanical methods. This book presents the recent research from around the world in this field.
Download or read book Energy Technology Perspectives 2010 written by International Energy Agency and published by Organization for Economic Co-Operation & Development. This book was released on 2010 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2010 edition of Energy Technology Perspectives examines the extent to which an energy technology revolution is taking place, the key technologies that are emerging, the costs and benefits of these technologies, and policies needed to foster their use. ETP 2010 presents updated scenarios from the present to 2050 that show which new technologies will be most important in key sectors and in different regions of the world. It highlights the importance of finance to achieve change, examines the implications of the scenarios for energy security and looks at how to accelerate the deployment of low-carbon technologies in major developing countries. It presents roadmaps and transition pathways for spurring deployment of the most important clean technologies and for overcoming existing barriers. With extensive data, projections and analysis, Energy Technology Perspectives 2010 provides decision makers with the detailed information and insights needed to accelerate the switch to a more secure, low-carbon energy future.
Download or read book Scientific Basis for Nuclear Waste Management XXII Volume 556 written by David J. Wronkiewicz and published by . This book was released on 1999-11-24 with total page 1370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safe and effective management of nuclear waste provides a broad range of challenges for materials science. Waste processing, waste form and engineered barrier properties, interactions between engineered and geological systems, radiation effects, chemistry and transport of waste species, and long-term predictions of repository performance are just some of the scientific problems facing modern society. This book, the 22nd in a very successful series from MRS, offers an international and inter-disciplinary perspective on the issues, and features developments in both fundamental and applied areas. Topics include: development and characterization of ceramic waste forms; ceramic waste form corrosion; glass waste form processing; glass formulation, properties and structure; glass waste form corrosion; spent nuclear fuel; performance assessment; repository backfill; flow and transport; natural analogues; container corrosion; metal waste form corrosion; radionuclide speciation and solubility; radionuclide sorption; microbial effects; radiation effects; cement waste forms and waste treatment.
Download or read book How to Design Wastewater Systems for Local Conditions in Developing Countries written by David M. Robbins and published by IWA Publishing. This book was released on 2014-03-15 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a practical handbook providing a step-by-step approach to the techniques used for characterizing wastewater sources and investigating sites where collection, treatment and reuse/disposal technologies will be installed. It is intended to help enable local implementation of on-site and decentralized wastewater management system (DWMS)for wide scale use in development settings. How to Design Wastewater Systems for Local Conditions in Developing Countries helps local service providers and regulatory officials make informed decisions through the use of tools, checklists and case studies. It includes a link to a web based community of on-site and decentralized wastewater professionals, which contains related tools and case studies. This handbook serves as a reference for training classes, certification programs, and higher education programs in civil and sanitary engineering. There is an increasing interest on the part of local government officials and private sector service providers to implement wastewater treatment systems to solve sanitation problems. The model presented in this handbook promotes activities that first generate data related to source and site conditions that represent critical inputs, and then applies this information to the technology selection process. Matching the most appropriate technologies to the specific needs of the wastewater project is the key that leads to long term sustainability. How to Design Wastewater Systems for Local Conditions in Developing Countries is an invaluable resource for public sector decision makers and private sector service providers in developing countries. It is also a useful text for students at engineering colleges in developing countries interested in taking a class that teaches the methods of decentralized wastewater management system (DWMS) development.
Download or read book Compendium of Sanitation Systems and Technologies written by Elizabeth Tilley and published by . This book was released on 2014 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific Basis for Nuclear Waste Management XXIII Volume 608 written by Robert W. Smith and published by . This book was released on 2000-10-09 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-standing symposia series has become the premier, international forum for scientific and engineering issues related to all levels and types of radioactive wastes and their management. Topics include: fuel cladding and spent nuclear fuel; container fabrication and corrosion; performance assessment; repository performance; radionuclide sorption and transport; cement-based materials and waste containment; corrosion of ceramic wasteforms; structure and characterization of ceramics; radiation effects; natural analogs; wasteform characterization and processing; and corrosion and characterization of glass wasteforms.
Download or read book Cambridge Yearbook of European Legal Studies Vol 13 2010 2011 written by Catherine Barnard and published by Bloomsbury Publishing. This book was released on 2011-12-15 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Cambridge Yearbook of European Legal Studies provides a forum for the scrutiny of significant issues in EU Law, the law of the European Convention on Human Rights, and Comparative Law with a 'European' dimension, and particularly those issues which have come to the fore during the year preceding publication. The contributions appearing in the collection are commissioned by the Centre for European Legal Studies (CELS) Cambridge, a research centre in the Law Faculty of the University of Cambridge specialising in European legal issues. The papers presented are at the cutting edge of the fields which they address, and reflect the views of recognised experts drawn from the University world, legal practice, and the institutions of both the EU and its Member States. Inclusion of the comparative dimension brings a fresh perspective to the study of European law, and highlights the effects of globalisation of the law more generally, and the resulting cross fertilisation of norms and ideas that has occurred among previously sovereign and separate legal orders. The Cambridge Yearbook of European Legal Studies is an invaluable resource for those wishing to keep pace with legal developments in the fast moving world of European integration. INDIVIDUAL CHAPTERS Please click on the link below to purchase individual chapters from Volume 13 through Ingenta Connect: www.ingentaconnect.com SUBSCRIPTION TO SERIES To place an annual online subscription or a print standing order through Hart Publishing please click on the link below. Please note that any customers who have a standing order for the printed volumes will now be entitled to free online access. www.hartjournals.co.uk/cyels/subs Editorial Advisory Board: Albertina Albors-Llorens, John Bell, Alan Dashwood, Simon Deakin, David Feldman, Richard Fentiman, Angus Johnston, John Spencer Founding Editors: Alan Dashwood and Angela Ward Ius Commune Prize 2012 Alexandre Saydé wrote Chapter 15 in this volume entitled: 'One Law, Two Competitions: An Enquiry into the Contradictions of Free Movement Law' and we are delighted to announce that he has been awarded the Ius Commune Prize 2012.
