Composition Modulation Of Catalytic Reactors

Composition modulation is a method of operating a catalytic reactor to improve catalyst activity or selectivity and has been under study for more than 25 years. In the last few years, several commercial applications have been realized and more will certainly appear. A large international research literature now exists. This book examines this literature and attempts to organize and analyze it with the intent of identifying the magnitude of improvements possible, why modulation is effective, and what questions remain unanswered. Topics include hydrogenation, oxidation, reduction, and polymerization reactions for NOX, SOX, NH3, and hydrocarbons.

This comprehensive review, prepared by 24 experts, many of whom are pioneers of the subject, brings together in one place over 40 years of research in this unique publication. This book will assist R & D specialists, research chemists, chemical engineers or process managers harnessing periodic operations to improve their process plant performance. Periodic Operation of Reactors covers process fundamentals, research equipment and methods and provides "the state of the art" for the periodic operation of many industrially important catalytic reactions. Emphasis is on experimental results, modeling and simulation. Combined reaction and separation are dealt with, including simulated moving bed chromatographic, pressure and temperature swing and circulating bed reactors. Thus, Periodic Operation of Reactors offers readers a single comprehensive source for the broad and diverse new subject. This exciting new publication is a "must have" for any professional working in chemical process research and development. A comprehensive reference on the fundamentals, development and applications of periodic operation Contributors and editors include the pioneers of the subject as well as the leading researchers in the field Covers both fundamentals and the state of the art for each operation scenario, and brings all types of periodic operation together in a single volume Discussion is focused on experimental results rather than theoretical ones; provides a rich source of experimental data, plus process models Accompanying website with modelling data

When talking about modelling it is natural to talk about simulation. Simulation is the imitation of the operation of a real-world process or systems over time. The objective is to generate a history of the model and the observation of that history helps us understand how the real-world system works, not necessarily involving the real-world into this process. A system (or process) model takes the form of a set of assumptions concerning its operation. In a model mathematical and logical assumptions are considered, and entities and their relationship are delimited. The objective of a model – and its respective simulation – is to answer a vast number of “what-if” questions. Some questions answered in this book are: What if the power distribution system does not work as expected? What if the produced ships were not able to transport all the demanded containers through the Yangtze River in China? And, what if an installed wind farm does not produce the expected amount of energyt? Answering these questions without a dynamic simulation model could be extremely expensive or even impossible in some cases and this book aims to present possible solutions to these problems.

Hydrodynamics, Mass and Heat Transfer in Chemical Engineering contains a concise and systematic exposition of fundamental problems of hydrodynamics, heat and mass transfer, and physicochemical hydrodynamics, which constitute the theoretical basis of chemical engineering in science. Areas covered include: fluid flows; processes of chemical engineeri

Adopts a completely original approach to the study of processes of mass transfer. In contrast to the usual approach, based on the concept of continuum media and the theory of heat and mass transfer, the topic is considered from a new viewpoint, taking into account the heterogeneous dispersal state of porous bodies. The author bases his discussion on the theory of surface forces and microhydrodynamic analysis of the processes of mass transport of gases, liquids and vapors, providing the reader with a systematic account of liquid/solid and gas/solid interfaces. Topics treated in this book include structural peculiarities, equilibrium and properties of liquids in porous bodies. Various mechanisms of mass transfer are considered, including liquid flow in pores and films, gas diffusion, combined transfer of liquid and vapor, convective diffusion in solutions, structure formation, capillary phenomena, and wetting. This unique book provides a wealth of information from the former Soviet Union, which will be of great interest to chemists, physicists and materials scientists, as well as industrialists working with a variety of different products in which disperse systems and porous bodies are important.

Fundamental techniques of mathematical modeling of processes essential to the food industry are explained in this text. Instead of concentrating on detailed theoretical analysis and mathematical derivations, important mathematical prerequisites are presented in summary tables. Readers' attention is focused on understanding modeling techniques, rather than the finer mathematical points. Topics covered include modeling of transport phenomena, kinetic processes, and food engineering operations. Statistical process analysis and quality control as applied to the food industry are also discussed. The book's main feature is the large number of worked examples presented throughout. Included are examples from almost every conceivable food process, most of which are based on real data given in the many references. Each example is followed by a clear, step- by-step worked solution.

Cyclic Separating Reactors is a critical examination of the literature covering periodically operated separating reactors incorporating an adsorbent as well as a catalyst, aiming to establish the magnitude of performance improvement available with this type of reactor compared to systems in which the reactor and separator are separate units. The adequacy of present models is considered by comparison of simulation and experimental studies, and gaps in understanding or experimental verification of model predictions are identified. Separating reactors, including chromatographic reactors and pressure swing reactors, are an expeditious means of process intensification, reducing both capital and operating costs, particularly where reactions are equilibrium limited. For this reason, cyclically operating separating reactors are attracting considerable interest across the range of chemical manufacturing industries, so this book is a timely and valuable summary of the literature available to the engineer. Following an introduction to multifunctional reactors and to periodic reactor operation, Cyclic Separating Reactors covers both chromatographic and pressure swing adsorption reactors, and is written for chemical engineers in both industry and academe. First book to critically examine the literature surrounding Cyclically Operating Separating Reactors providing a straightforward entry to, and detailed appraisal of, the literature, so the reader does not have to engage in an expensive and time consuming literature review Evaluates current models and understanding to give the engineer clear information on what performance can be expected of these reactors and where current information needs to be augmented when designing systems for commercial operation.

The spillover effect is one of the most promising factors in the enhancement of catalytic reaction rates. The spillover phenemenon was found in the 1960s by several research groups independently. It was defined at the previous International Symposium on Spillover as follows Spillover involves the transport of active species which are adsorbed or formed on a first phase onto another phase that does not adsorb or form the species under the same condition. However, this effect appears typically in the dynamic state, i.e., during reactions, which advance with a considerable reaction rate. This makes it difficult to elucidate the spillover effect through static methods. Therefore, more fundamental investigations are necessary. The development of alternative energy sources and protection of the environment demands highly selective and very rapid catalytic reactions at deviating conditions. To achieve these goals new concepts, such as the spillover effect, are needed. This proceedings book, which comprises 80 papers, contains methods for preparing catalysts in order to realize spillover effects and suggests the most probable mechanisms to explain these non-linear phenomena. It also contains studies on applications of the spillover effect to improve industrial catalytic processes. The book will be invaluable in the development of industrial catalysts and for solving energy and environmental protection problems.