Supercritical Fluids


Book Description

Supercritical fluids are neither gas nor liquid, but can be compressed gradually from low to high density and they are therefore interesting and important as tunable solvents and reaction media in the chemical process industry. By adjusting the density the properties of these fluids can be customised and manipulated for a given process - physical or chemical transformation. Separation and processing using supercritical solvents such as CO2 are currently on-line commercially in the food, essential oils and polymer industries. Many agencies and industries are considering the use of supercritical water for waste remediation. Supercritical fluid chromatography represents another, major analytical application. Significant advances have recently been made in materials processing, ranging from particle formation to the creation of porous materials. The chapters in this book provide tutorial accounts of topical areas centred around: (1) phase equilibria, thermodynamics and equations of state; (2) critical behaviour, crossover effects; (3) transport and interfacial properties; (4) molecular modelling, computer simulation; (5) reactions, spectroscopy; (6) phase separation kinetics; (7) extractions; (8) applications to polymers, pharmaceuticals, natural materials and chromatography; (9) process scale-up.




Packed Column SFC


Book Description

Packed Column SFC is the third title to be published in this series and has been produced as a result of the dramatic re-emergence, in the last three years, of packed column instrumentation. This has led to a redefinition of the technique and an urgent need for a practical guide that deals with its subtleties. This book fulfils that need and deals exclusively with packed column SFC. It places the emphasis on understanding the underlying chemistry in order to perform rapid, systematic optimizations and provides many practical tips to help the new user avoid problems unique to SFC. It also proposes a detailed scheme for method development and provides lists of prioritized guidelines. The book clears up some of the confusion that surrounds the analytical use of supercritical fluids and assists the user in understanding the power and utility of this technique. Detailed chapters cover the most promising new application areas for packed column SFC, which are often overlooked in the mainstream chromatography literature. Like the other books in this popular series, Packed Column SFC will prove an invaluable guide and is essential reading for graduates, postgraduates and researchers with interests in pharmaceuticals, agricultural chemistry, small polar drug molecules, chiral analysis, environmental chemistry, and chromatography/instrumentation.




Supercritical Fluids


Book Description

Supercritical fluids which are neither gas nor liquid, but can be compressed gradually from low to high density, are gaining increasing importance as tunable solvents and reaction media in the chemical process industry. By adjusting the pressure, or more strictly the density, the properties of these fluids are customized and manipulated for the particular process at hand, be it a physical transformation, such as separation or solvation, or a chemical transformation, such as a reaction or reactive extraction. Supercritical fluids, however, differ from both gases and liquids in many respects. In order to properly understand and describe their properties, it is necessary to know the implications of their nearness to criticality, to be aware of the complex types of phase separation (including solid phases) that occur when the components of the fluid mixture are very different from each other, and to develop theories that can cope with the large differences in molecular size and shape of the supercritical solvent and the solutes that are present.




Frontiers in Chemical Engineering


Book Description

In the next 10 to 15 years, chemical engineers have the potential to affect every aspect of American life and promote the scientific and industrial leadership of the United States. Frontiers in Chemical Engineering explores the opportunities available and gives a blueprint for turning a multitude of promising visions into realities. It also examines the likely changes in how chemical engineers will be educated and take their place in the profession, and presents new research opportunities.




Unified Chromatography


Book Description

Here, authors specializing in different branches of chromatography--including gas chromatography, supercritical fluid chromatography, and high-pressure liquid chromatography--describe their fields while drawing out connections with other branches.




Organic Chemistry


Book Description

Provides the background, tools, and models required to understand organic synthesis and plan chemical reactions more efficiently Knowledge of physical chemistry is essential for achieving successful chemical reactions in organic chemistry. Chemists must be competent in a range of areas to understand organic synthesis. Organic Chemistry provides the methods, models, and tools necessary to fully comprehend organic reactions. Written by two internationally recognized experts in the field, this much-needed textbook fills a gap in current literature on physical organic chemistry. Rigorous yet straightforward chapters first examine chemical equilibria, thermodynamics, reaction rates and mechanisms, and molecular orbital theory, providing readers with a strong foundation in physical organic chemistry. Subsequent chapters demonstrate various reactions involving organic, organometallic, and biochemical reactants and catalysts. Throughout the text, numerous questions and exercises, over 800 in total, help readers strengthen their comprehension of the subject and highlight key points of learning. The companion Organic Chemistry Workbook contains complete references and answers to every question in this text. A much-needed resource for students and working chemists alike, this text: -Presents models that establish if a reaction is possible, estimate how long it will take, and determine its properties -Describes reactions with broad practical value in synthesis and biology, such as C-C-coupling reactions, pericyclic reactions, and catalytic reactions -Enables readers to plan chemical reactions more efficiently -Features clear illustrations, figures, and tables -With a Foreword by Nobel Prize Laureate Robert H. Grubbs Organic Chemistry: Theory, Reactivity, and Mechanisms in Modern Synthesis is an ideal textbook for students and instructors of chemistry, and a valuable work of reference for organic chemists, physical chemists, and chemical engineers.







Molecular Gels


Book Description

"Molecular Gels: Materials with Self-Assembled Fibrillar Networks" is a comprehensive treatise on gelators, especially low molecular-mass gelators and the properties of their gels. The structures and modes of formation of the self-assembled fibrillar networks (SAFINs) that immobilize the liquid components of the gels are discussed experimentally and theoretically. The spectroscopic, rheological, and structural features of the different classes of low molecular-mass gelators are also presented. Many examples of the application of the principal analytical techniques for investigation of molecular gels (including SANS, SAXS, WAXS, UV-vis absorption, fluorescence and CD spectroscopies, scanning electron, transmission electron and optical microscopies, and molecular modeling) are presented didactically and in-depth, as are several of the theories of the stages of aggregation of individual low molecular-mass gelator molecules leading to SAFINs. Several actual and potential applications of molecular gels in disparate fields (from silicate replication of nanostructures to art conservation) are described. Special emphasis is placed on perspectives for future developments. This book is an invaluable resource for researchers and practitioners either already researching self-assembly and soft matter or new to the area. Those who will find the book useful include chemists, engineers, spectroscopists, physicists, biologists, theoreticians, and materials scientists.