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Aufgrund der steigenden Nachfrage an Lithium werden effektive Verfahren zur Lithium-produktion gesucht. Die größten Lithiumvorkommen sind die Salzseen Südamerikas: Salar de Atacama in Chile und Salar de Uyuni in Bolivien. Im Rahmen dieser Arbeit sollten qualifizierbare Prozessgrundlagen erarbeitet werden. Als Ausgangsmaterial kam eine eingetrocknete Salzmischung des Salar de Uyuni kurz nach der Carnallitabscheidung zum Einsatz. Der Hauptbestandteil war Bischofit neben Lithiumchlorid. Zur Calcinierung wurde ein geeigneter Ofenprozess für die Erzeugung einer größeren Menge Röstgut unter reproduzierbaren Bedingungen entwickelt. Die Extrahierbarkeit von wasserlöslichen Lithiumsalzen aus calciniertem Magnesiumoxid wurde in verschiedenen Laugungsexperimenten untersucht. Mit diesen Grundlagen wurde eine Material- und Energiebilanz für die Erzeugung von 1 t Li2CO3 erstellt und im Zusammenhang mit der Nutzung verschiedener Energiearten diskutiert.

This book covers all the basic and applied aspects of crystallization processes based on membrane technology. Synthesis and processing of membrane materials are discussed and reviewed, while mass/heat transport and control are treated in view of the non-reversible thermodynamic principles and statistical thermodynamics. Engineering process design and crystalline materials products properties, and also the relation to other traditional crystallization formats, are analyzed. Advantages, limitations, and future developments are also included in the content, with special emphasis on new fields of applications like microfluidic configurations, controlled proteins (also membrane proteins) crystallization, organic semiconductors single crystals production, and optical materials.

This collection conta ins the results of a number of investiga­ tions which have been carried out in the Hydrothermal Synthesis Laboratory of the Institute of Crystallography, Academy of Sciences of the USSR; it constitutes a continuation of an earlier collection which appeared in 1968: Hydrothermal Synthesis of Crystals. Problems associated with the synthesis of oxides, simple and complex sulfides, carbonates, silicates, and germanates are consid­ ered, and a great deal of factual material relating to the growth of single crystals of some of these compounds on a seed is presented. Some of the articles pay special attention to the kinetic asp­ ect of the growth of crystals; the conditions of growth are relat­ ed to the morphological characteristics of the growing faces, and the relationship between the habit of the crystals and the oomposi­ tion and constitution of the solutions is considered. A fair number of articles are concerned with the crystalliza­ tion of new compounds, most of which have now been synthesized under hydrothermal conditions for the very first time; these in­ clude ternary chalcohalides of composition AVBvIVVII. zirconates, lithium silicates, and germanates. The collection also contains a description of the apparatus used for precision measurements at high temperatures and pres­ sures. We hope that this publication will present a better idea of the special characteristics of the hydrothermal method of synthes­ izing and.growing crystals, and will prove useful to all those in­ terested in this field of knowledge.

Title from PDF cover (viewed May 4, 2012).

Structure formation in crystallizing polymers, as occurring during processing, has not been treated so far in a coherent form. This fact explains, why this monograph is written as the?rst book devoted to this subject. A quarter of a century ago the underdevelopment of this subject was obvious. Trial and error dominated. In fact, other apposite subjects as polymer melt rheology or heat transfer, had reached high levels. A great number of books has been devoted to them. Mold?lling of amorphous polymers and the solidi?cation of these polymers by vitri?cation can nowadays be simulated numerically with a high degree of accuracy. In the solidi?ed sample even residual stresses and corresponding birefringence effects can accurately be 1 calculated. However, semicrystalline polymers, which form the majority of industrial po- mers, have been excluded from these considerations for good reasons. In fact, great uncertainties existed about the formation of quality determining crystalline str- tures. In particular, polyole?ns suffered from this shortcoming. In 1983 this fact instigated the polymer research group at the Johannes Kepler University in Linz to start with pertinent activities. The urgency of this kind of studies becomes evident, if advantages and hitches of these polymers are considered. 1. Versatility of processing: Injection molding into a great variety of shapes and sizes, from thin walled beakers to garden chairs, not to forget pipe and pro?le extrusion, cable coating,?ber spinning,?lm blowing. 2. Product qualities: Ductility, low density, good electric insulation, corrosion resistance, surface quality.

The crystallization of proteins and nucleic acids and/or their complexes has become more highly automated but is still often a trial and error based approach. In parallel, a number of X-ray diffraction based techniques have been developed which explain the physical reasons limiting the resulting crystallographic data and thus show how that data may be improved. Crystal growth is also pivotal in neutron crystallography, which establishes the hydrogen and hydration aspects. Thus this book is aimed at addressing the science behind obtaining the best and most complete structural data possible for biological macromolecules, so that the detailed structural biology and chemistry of these important molecules emerge. Crystal imperfections such as twinning and lattice disorders, as well as multiple crystal situations, and their possible remedies, are also described. The small crystal frontier in micro-crystal crystallography, crystallites in powders and finally down to the proposed single molecule structure determination of X-ray lasers are covered. Overall this interdisciplinary book will interest crystal growers, X-ray and neutron physicists and the biological crystallographers, including graduate students.

It is particularly symptomatic that a volume concerning P-T-X phase equilibrium should appear in the Materials Science Series. Entering the 21st century, progress in modern electronics is increasingly becoming associated with devices based not only on silicon but also on chemical compounds. These include both semiconduc­ tors and, in the last 15 years, multinary oxides with high-To superconductor properties. The critical role of chemical processes in the technologies of these materials is quite evident, and in recent years has stimulated vigorous research activity in the physical chemistry of materials, resulting in a renaissance of this field. The leading role in these efforts belongs to thermodynamics, in particular, computer modeling of chemical processes, phase equilibrium, and controlled synthesis of inorganic materials with preliminary fixed stoichiometric composition. Especially important contributions have been made regarding non­ stoichiometry and our understanding of the crucial relationship between composition and properties of the materials since the development of the vapor pressure scanning approach to the phenomenon of non-stoichiometry. This method of the in situ investigation of the crystal composition directly at high temperatures 3 4 proved to be of an unparalleled precision of 10- _10 at.% and made it possible to obtain in an analytical form functional dependences of the crystal composition on temperature, pressure, and composition of the crystallizing matrix for crystals with sub-O. l at.% range of existence.

Theory of Particulate Processes: Analysis and Techniques of Continuous Crystallization, Second Edition covers the numerous population balance-based particulate studies. This edition emerged from the notes for an industrial short course on crystallization. This book is divided into 10 chapters and begins with an outline of the methods for representation of particle distributions and a systematic approach to the predictive modeling of processes where there is a need to characterize distributions in time and space and by some identifying property. The succeeding chapters provide a specific and more elementary approach to modeling crystal size distributions, as well as the modeling the kinetics of crystal nucleation and growth rates. Other chapters discuss a wide range of system analysis and design considerations specific to crystallization for both the steady state and unsteady state. The final chapters illustrate the use of a population balance analysis to interpret data from both laboratory and process equipment. These chapters also explore a wide variety of particulate processes and systems for which the population balance analysis is useful. This book is of great value to graduate students with particulate systems course.