Author: M. Guisnet
Publisher: World Scientific
ISBN: 1848166370
Category : Science
Languages : en
Pages : 359
Get Book Here
Book Description
In chemical processes, the progressive deactivation of solid catalysts is a major economic concern and mastering their stability has become as essential as controlling their activity and selectivity. For these reasons, there is a strong motivation to understand the mechanisms leading to any loss in activity and/or selectivity and to find out the efficient preventive measures and regenerative solutions that open the way towards cheaper and cleaner processes. This book covers in a comprehensive way both the fundamental and applied aspects of solid catalyst deactivation and encompasses the state-of-the-art in the field of reactions catalyzed by zeolites. This particular choice is justified by the widespread use of molecular sieves in refining, petrochemicals and organic chemicals synthesis processes, by the large variety in the nature of their active sites (acid, base, acid-base, redox, bifunctional) and especially by their peculiar features, in terms of crystallinity, structural order and textural properties, which make them ideal models for heterogeneous catalysis. The aim of this book is to be a critical review in the field of zeolite deactivation and regeneration, by collecting a series of contributions by experts in the field which describe the factors, explain the techniques to study the causes and suggest methods to prevent (or limit) catalyst deactivation. At the same time, an anthology of commercial processes and exemplar cases provides the reader with theoretical insights and practical hints on the deactivation mechanisms and draws attention to the key role played by the loss of activity on process design and industrial practice.
Author: Luciana Lisi
Publisher: MDPI
ISBN: 3039215469
Category : Science
Languages : en
Pages : 254
Get Book Here
Book Description
Catalyst lifetime represents one of the most crucial economic aspects in industrial catalytic processes, due to costly shutdowns, catalyst replacements, and proper disposal of spent materials. Not surprisingly, there is considerable motivation to understand and treat catalyst deactivation, poisoning, and regeneration, which causes this research topic to continue to grow. The complexity of catalyst poisoning obviously increases along with the increasing use of biomass/waste-derived/residual feedstocks and with requirements for cleaner and novel sustainable processes. This book collects 15 research papers providing insights into several scientific and technical aspects of catalyst poisoning and deactivation, proposing more tolerant catalyst formulations, and exploring possible regeneration strategies.
Author: John B. Butt
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 520
Get Book Here
Book Description
Author: J. Oudar
Publisher: CRC Press
ISBN: 9780824773380
Category : Science
Languages : en
Pages : 356
Get Book Here
Book Description
Deactivation and Poisoning of Catalysts presents the most current research in the area of heterogeneous catalysis. It focuses on the chemically induced effects associated with bonded surface species that cause catalyst activity decline -- and in some cases a change in catalyst specificity. In addition, this volume examines poisoning of dispersed metal catalysts ... the thermodynamics of sulfur-metal and carbon-metal interactions ... model poisoning reactions on single crystals ... deactivation in petroleum refining and petrochemical processes ... coking of metal catalysts ... and more. The new approaches and solutions to catalyst deactivation and poisoning presented in this guide are invaluable to all heterogeneous catalysis specialists, including chemical and petroleum engineers, and surface, synthetic, physical, and industrial chemists. Book jacket.
Author: Guisnet Michel
Publisher: World Scientific Publishing Company
ISBN: 1911299530
Category : Science
Languages : en
Pages : 360
Get Book Here
Book Description
In chemical processes, the progressive deactivation of solid catalysts is a major economic concern and mastering their stability has become as essential as controlling their activity and selectivity. For these reasons, there is a strong motivation to understand the mechanisms leading to any loss in activity and/or selectivity and to find out the efficient preventive measures and regenerative solutions that open the way towards cheaper and cleaner processes. This book covers the fundamental and applied aspects of solid catalyst deactivation in a comprehensive way and encompasses the state of the art in the field of reactions catalyzed by zeolites. This particular choice is justified by the widespread use of molecular sieves in refining, petrochemicals and organic chemicals synthesis processes, by the large variety in the nature of their active sites (acid, base, acid-base, redox, bifunctional) and especially by their peculiar features, in terms of crystallinity, structural order and textural properties, which make them ideal models for heterogeneous catalysis. The aim of this book is to be a critical review in the field of zeolite deactivation and regeneration by collecting contributions from experts in the field which describe the factors, explain the techniques to study the causes and suggest methods to prevent (or limit) catalyst deactivation. At the same time, a selection of commercial processes and exemplar cases provides the reader with theoretical insights and practical hints on the deactivation mechanisms and draws attention to the key role played by the loss of activity on process design and industrial practice./a
Author: Manfred Baerns
Publisher: Springer Science & Business Media
ISBN: 3662059819
Category : Science
Languages : en
Pages : 540
Get Book Here
Book Description
Written by a team of internationally recognized experts, this book addresses the most important types of catalytic reactions and catalysts as used in industrial practice. Both applied aspects and the essential scientific principles are described. The main topics can be summarized as follows: heterogeneous, homogeneous and biocatalysis, catalyst preparation and characterization, catalytic reaction engineering and kinetics, catalyst deactivation and industrial perspective.
Author: John Butt
Publisher: Elsevier
ISBN: 0323140866
Category : Technology & Engineering
Languages : en
Pages : 506
Get Book Here
Book Description
Activation, Deactivation, and Poisoning of Catalysts deals with the circumstances and mechanisms underlying catalyst activation, deactivation, and poisoning. The emphasis is on the techniques for handling deactivating systems, not on results per se. Deactivation by fouling and sintering is given consideration. This book is organized into three sections and consists of 12 chapters. The first part is devoted to a systematic development of the manner in which catalysts are activated, deactivated, poisoned, and in some cases reactivated on a microscopic basis. The first chapter explains the concept of the active center as utilized in catalysis, along with catalyst regeneration, rejuvenation, and detoxification. In the second part, the reader is introduced to the problem of heat transfer as well as the transport of reactants and products in the interior of the particle coupled with chemical reaction therein. The macroscopic deactivation behavior of the catalyst particle is described in terms of fundamental kinetic deactivation phenomena and of parameters governing heat and mass transfer. The last part is primarily concerned with a collection of catalyst particles within the reactor, with emphasis on the global activity of the reactor. In the last chapter, a pragmatic approach is presented to predict the design and performance of chemical reactors containing a deactivating catalyst. This book is written for catalytic chemists, researchers, reactor designers, and students interested in catalyst activation, deactivation, and poisoning.
Author: Farid Gumerov
Publisher: Nova Science Publishers
ISBN: 9781634843096
Category : Catalysts
Languages : en
Pages : 0
Get Book Here
Book Description
A catalyst is a material of constant composition, which accelerates the rate of a chemical reaction by providing a suitable reaction pathway with the lowest activation energy. As the activation energy is lower, more reaction products are formed in the same period of time. Most catalytic reactions encountered in hydrocarbon processing are carried out with porous catalysts to provide a sufficient surface area for the metal dispersion and the ensuing reaction. These catalysts gradually lose their catalytic activity, usually through structural changes, poisoning, or the deposit of extraneous material. A catalyst which can no longer exhibit the necessary activity and/or is specificity required by the user is referred to as a "spent catalyst". Catalysts are critical to the chemical industry and are now used in most industrial chemical processes. Along with the rapid development and wide application of catalysis technology, the amounts of different spent catalysts are increased from year to year. The physical properties of spent catalysts, as well as their composition, are generally different from those of fresh catalysts. For example, spent hydrotreating catalysts contain metal sulfides and coke, and may have additional contaminants that were not present in the fresh catalyst. Catalyst regeneration involves the processing of spent catalysts in order to make them reusable. This is done by restoring the initial properties of spent catalysts and thus restoring their efficiency through a process called regeneration of catalysts. Traditional methods of vapor-air regeneration are energy-consuming and severely limit the number of regeneration cycles. Using supercritical fluid CO2-extraction process, according to some estimates, provides a two-fold energy savings and an increasing number of regeneration cycles possible. This book gathers a series of studies describing new methods for the regeneration of heterogeneous catalysts for important industrial chemical processes. In this book we propose new extraction techniques using supercritical fluid extraction (SFC), which seems to be one of the most promising as a green reaction medium. The feasibility of using supercritical fluid СО2 extraction process was investigated in particular for spent catalyst regeneration. The low regeneration temperature of supercritical carbon dioxide eliminates the risk of thermal deterioration of the catalyst (namely the collapse of the pores), prevents the reduction of the surface area and the sintering, and allows regeneration of catalysts with an activity close to that of fresh catalysts. The results of the implementation of the supercritical fluid СО2 extraction process with respect to samples of industrial deactivated catalysts are provided. A comparison of the characteristics of the regenerated catalyst samples by traditional approaches and the SC-CO2 extraction process is carried out. The possibility of using a supercritical fluid CO2 impregnation technique in the synthesis of a palladium catalyst is also studied.
Author: Howard F. Rase
Publisher: CRC Press
ISBN: 1482275368
Category : Science
Languages : en
Pages : 514
Get Book Here
Book Description
Despite the advances in understanding the phenomena that occur on a catalyst surface, much of the successful catalyst development and use continues to be half science and half art. The art resides in the practical knowledge of experts in the development and use of commercial catalysts-it comes with experience. Now the background needed to nurture t
Author: Luciana Lisi
Publisher:
ISBN: 9783039215478
Category : Electronic books
Languages : en
Pages : 1
Get Book Here
Book Description
Catalyst lifetime represents one of the most crucial economic aspects in industrial catalytic processes, due to costly shutdowns, catalyst replacements, and proper disposal of spent materials. Not surprisingly, there is considerable motivation to understand and treat catalyst deactivation, poisoning, and regeneration, which causes this research topic to continue to grow. The complexity of catalyst poisoning obviously increases along with the increasing use of biomass/waste-derived/residual feedstocks and with requirements for cleaner and novel sustainable processes. This book collects 15 research papers providing insights into several scientific and technical aspects of catalyst poisoning and deactivation, proposing more tolerant catalyst formulations, and exploring possible regeneration strategies.
