Mechanisms In Homogeneous And Heterogeneous Epoxidation Catalysis

The catalytic epoxidation of olefins plays an important role in the industrial production of several commodity compounds, as well as in the synthesis of many intermediates, fine chemicals, and pharmaceuticals. The scale of production ranges from millions of tons per year to a few grams per year. The diversity of catalysts is large and encompasses all the known categories of catalyst type: homogeneous, heterogeneous, and biological. This book summarizes the current status in these fields concentrating on rates, kinetics, and reaction mechanisms, but also covers broad topics including modeling, computational simulation, process concepts, spectroscopy and new catalyst development. The similarities and distinctions between the different reaction systems are compared, and the latest advances are described. * Comprehensive listing of epoxide products * Broad comparison of turnover frequencies of homogeneous, hetergeneous, main-group, biomimetic and biological catalysts * Analysis of the general strengths and weaknesses of varied catalytic systems * Detailed description of the mechanisms of reaction for classical and emerging catalysts

Over the last decade, the area of homogeneous catalysis with transition metal has grown in great scientific interest and technological promise, with research in this area earning three Nobel Prizes and filing thousands of patents relating to metallocene and non-metallocene single site catalysts, asymmetric catalysis, carbon-carbon bond forming metathesis and cross coupling reactions. This text explains these new developments in a unified, cogent, and comprehensible manner while also detailing earlier discoveries and the fundamentals of homogeneous catalysis. Serving as a self-study guide for students and all chemists seeking to gain entry into this field, it can also be used by experienced researchers from both academia and industry for referring to leading state of the art review articles and patents, and also as a quick self-study manual in an area that is outside their immediate expertise. The book features: • Topics including renewable feed stocks (biofuel, glycerol), carbon dioxide based processes (polycarbonates), fluorous solvents, ionic liquid, hydroformylation, polymerization, oxidation, asymmetric catalysis, and more • Basic principles of organometallic chemistry, homogeneous catalysis, and relevant technological issues • Problems and answers, industrial applications (case studies), and examples from proven industrial processes with clear discussions on environmental and techno-commercial issues • Extensive references to cutting edge research with application potential and leading patents • Tables and illustrations to help explain difficult concepts

Heterogeneous catalysis has developed over the past two centuries as a technology driven by the needs of society, and is part of Nobel Prize-winning science. This book describes the spectacular increase in molecular understanding of heterogenous catalytic reactions in important industrial processes. Reaction mechanism and kinetics are discussed with a unique focus on their relation with the inorganic chemistry of the catalyst material. An introductory chapter presents the development of catalysis science and catalyst discovery from a historical perspective. Five chapters that form the thrust of the book are organized by type of reaction, reactivity principles, and mechanistic theories, which provide the scientific basis to structure-function relationships of catalyst performance. Present-day challenges to catalysis are sketched in a final chapter. Written by one of the world's leading experts on the topic, this definitive text is an essential reference for students, researchers and engineers working in this multibillion-dollar field.

The features of this book which will be of special interest to academic organic chemists are the introduction (Chapter 1), which presents a short course on the concepts and language of heterogeneous catalysis, covers organic reaction mechanisms of hydrogenation (Chapter 2), hydrogenolysis (Chapter 4), and oxidation (Chapter 6), a presents problems and solutions specific for running heterogeneous catalytic organic reactions in solution. These materials can supplement advanced chemistry courses. Most synthetic organic chemists use a variety of "protecting groups" which they attach to functional groups (reactive groups of atoms) while some reaction is being conducted on another part of the molecule. These protecting groups prevent reactions of the functional groups during other reactions and are removed later by a heterogeneous catalytic method called hydrogenolysis. One unique feature of this book, not found in other books on catalysis, is an exhaustive chapter (Chapter 4) on hydrogenolysis, which is dredged from the recent synthetic literature published by modern organic chemists. Academic organic chemists should find this chapter extremely useful and may wish to adopt the book as a supplement for advanced organic chemistry courses designed for seniors and for graduate students. It will also be useful for professors and their research groups engaged in synthetic organic chemistry. Many academic organic chemists are not aware of recent advances in heterogeneous enantioselective catalysis (Chapter 3) or in selective low temperature, liquid phase heterogeneous catalytic oxidations by hydrogen peroxide (Chapter 6). These specialty topics are timely and may be new to academic organic chemists and can be used to supplement their advanced courses. Several features of this book will also be of special interest to industrial chemists who are unfamiliar with heterogeneous catalysis. Many good organic chemists are hire by industry. They synthesize a new compound using standard organic synthetic techniques but are informed by their supervisor that they must convert some of their synthetic steps into heterogeneous catalytic steps. They may not have been exposed to heterogeneous catalysis and have few places to turn. This book offers them a crash course in heterogeneous catalysis as well as many examples of reactions and conditions with which they can start their search. Those industrial organic chemists already familiar with heterogeneous catalysis will find this book useful as a reference to many examples in the recent literature. They will find recent surface science discoveries correlated with heterogeneous catalysis or organic reactions and mechanistic suggestions designed to stimulate innovative nontraditional thinking about organic reactions on surfaces. Written by organic chemists for organic chemists Introduces heterogeneous catalysis concepts and language Presents a comprehensive compilation of protecting group removal procedures Covers liquid-phase hydrogenations, hydrogenolysis, and oxidations Addresses heterogeneous methods for producing pure enantiomers of chiral products Examines the emerging field of heterogenized homogeneous catalysts Mixes practical applications with mechanistic interpretations

This book consists of two parts: the first one deals with kinetics of processes in heterogeneous systems and those with different degrees of phase dispersion. Strict analytic methods are recommended for solving the kinetic equations for non-catalytic processes in gas, liquid, and solid phases herein. The second part of the book is devoted to studying structure and properties of catalysts and to the developing of catalysis theories. Kinetic methods to describe catalytic process have been worked out. Mechanisms of elementary catalytic stages are under consideration: theoretical methods of selecting catalysts for chemical reactions are being suggested on the basis of the theory of catalysis by polyhedra and Generalised Quantum-Chemical Principle. Mechanisms of adsorption, homogenous and heterogeneous catalysis, are under consideration. Theoretical parts are illustrated by problems with solutions.

This book describes a detailed multi-scale approach integrating nano- (active site), meso- (porous catalyst architecture) and macroscale (reactor) efforts, to address the challenges of producing a better epoxidation catalyst. It contains an in-depth study of the design and synthesis of gold nanoparticles and their application as a catalyst for direct gas phase propylene epoxidation. “Direct” means using only hydrogen and oxygen in one step, which is key for sustainable manufacturing, as opposed to commercialised, more complex production routes requiring multiple steps, or integration with another chemical plant. The insights gained can be used for rational design for stable and selective catalysts for other reactions. It also details the step-by-step process to build an epoxidation reactor system with a focus on safety aspects, which can be used as a guidebook for undergraduate and graduate students in chemical engineering. Beyond heterogeneous catalysis, the new, easily accomplished methodology for synthesising atomically precise nanoparticles is shown to be relevant to electrocatalysis and to healthcare applications, such as anti-microbial surfaces. This book will be of interest to researchers, engineers and experts in the related areas of chemical engineering, chemistry, material science and electrochemistry.

The book includes a historical introduction to organometallic chemistry, a survey of mechanisms, and an extensive introduction to quantum mechanical computational methods.

Catalysis is a multidisciplinary activity which is reflected in this book. The editors have chosen a novel combination of basic disciplines - homogeneous catalysis by metal complexes is treated jointly with heterogeneous catalysis with metallic and non-metallic solids. The main theme of the book is the molecular approach to industrial catalysis. In the introductory section Chapter 1 presents a brief survey of the history of industrial heterogeneous and homogeneous catalysis. Subsequently, a selection of current industrial catalytic processes is described (Chapter 2). A broad spectrum of important catalytic applications is presented, including the basic chemistry, some engineering aspects, feedstock sources and product utilisation. In Chapter 3, kinetic principles are treated. The section on fundamental catalysis begins with a description of the bonding in complexes and to surfaces (Chapter 4). The elementary steps on complexes and surfaces are described. The chapter on heterogeneous catalysis (5) deals with the mechanistic aspects of three groups of important reactions: syn-gas conversion, hydrogenation, and oxidation. The main principles of metal and metal oxide catalysis are presented. Likewise, the chapter on homogeneous catalysis (6) concentrates on three reactions representing examples from three areas: carbonylation, polymerization, and asymmetric catalysis. Identification by in situ techniques has been included. Many constraints to the industrial use of a catalyst have a macroscopic origin. In applied catalysis it is shown how catalytic reaction engineering deals with such macroscopic considerations in heterogeneous as well as homogeneous catalysis (Chapter 7). The transport and kinetic phenomena in both model reactors and industrial reactors are outlined. The section on catalyst preparation (Chapters 8 and 9) is concerned with the preparation of catalyst supports, zeolites, and supported catalysts, with an emphasis on general principles and mechanistic aspects. For the supported catalysts the relation between the preparative method and the surface chemistry of the support is highlighted. The molecular approach is maintained throughout. The first chapter (10) in the section on catalyst characterization summarizes the most common spectroscopic techniques used for the characterisation of heterogeneous catalysts such as XPS, Auger, EXAFS, etc. Temperature programmed techniques, which have found widespread application in heterogeneous catalysis both in catalyst characterization and simulation of pretreatment procedures, are discussed in Chapter 11. A discussion of texture measurement, theory and application, concludes this section (12). The final chapter (13) gives an outline of current trends in catalysis. Two points of view are adopted: the first one focusses on developments in process engineering. Most often these have their origin in demands by society for better processes. The second point of view draws attention to the autonomous developments in catalysis, which is becoming one of the frontier sciences of physics and chemistry. In this book emphasis is on those reactions catalyzed by heterogeneous and homogeneous catalysts of industrial relevance. The integrative treatment of the subject matter involves many disciplines, consequently, the writing of the book has been a multi-author task. The editors have carefully planned and harmonized the contents of the chapters.