Revival


Book Description




Supercritical Fluid Technology (1991)


Book Description

In this volume, we have collected a series of reviews that cover both experimental and theoretical work geared toward the more exact requirements of current SFE applications. While we have artificially divided the volume into experimental and theoretical sections, natural overlaps will be apparent. Many of the papers on experimental and theoretical sections, natural overlaps will be apparent. Many of the papers on experimental technique contain discussions on equation of state correlations. Indeed, a good deal of the experimental work is intimately tied to a mathematical description of fluid mixtures. The theoretical section presents reviews that cover the modern theory of critical phenomena, methods to correlate near critical experimental results and approaches to understanding the behavior of near critical fluids from microscopic theory. It is hoped that the scope of these reviews will provide the reader with the basis to further develop our understanding of the behavior of supercritical fluids.




Applications of Supercritical Fluids in Industrial Analysis


Book Description

The continued search for rapid, efficient and cost-effective means of analytical measurement has introduced supercritical fluids into the field of analytical chemistry. Two areas are common: supercritical fluid chroma tography and supercritical fluid extraction. Both seek to exploit the unique properties of a gas at temperatures and pressures above the critical point. The most common supercritical fluid is carbon dioxide, employed because of its low critical temperature (31 °C), inertness, purity, non-toxicity and cheapness. Alternative supercritical fluids are also used and often in conjunction with modifiers. The combined gas-like mass transfer and liquid-like solvating characteristics have been used for improved chroma tographic separation and faster sample preparation. Supercritical fluid chromatography (SFC) is complementary to gas chro matography ( GC) and high performance liquid chromatography (HPLC), providing higher efficiency than HPLC, together with the ability to analyse thermally labile and high molecular weight analytes. Both packed and open tubular columns can be employed, providing the capability to analyse a wide range of sample types. In addition, flame ionization detection can be used, thus providing 'universal' detection.




Supercritical Fluid Technology in Materials Science and Engineering


Book Description

This title analyzes the chemical reactions, structures and fundamental properties of supercritical fluid systems for the production of new compounds, nanomaterials, fibers, and films. It complies contemporary research and technological advances for increased selectivity and reduced waste in chemical, industrial, pharmaceutical, and biomedical applications. Topics include fluid dynamics, catalysis, hydrothermal synthesis, surfactants, conducting polymers, crystal growth, and other aspects and applications of supercritical fluids.




The Experimental Determination of Solubilities


Book Description

* Guidelines are provided on the reliability of various methods, as well as information for selecting the appropriate technique. * Unique coverage of the whole range of solubility measurements. * Very useful for investigators interested in embarking upon solubility measurements.




Supercritical Fluids


Book Description

The potential of supercritical fluid methods is presented in a comprehensive way. On the basis of a careful discussion of physical and chemical principles, the application of this method in process technology is demonstrated.







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.




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.




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.