摘要:

International Bunsen Discussion Meeting of the Deutsche Bunsen-Gesellschaft für Physikalische Chemie, Walberberg, Germany, 19–22 August, 2001.The phase behaviour of mixtures is the basis and objective for research ranging from fundamental to applied topics. This includes the investigation of molecular interactions in condensed matter as well as the analysis of phenomena of interest to material sciences. The understanding of phase behaviour is furthermore mandatory for the development in separation technology ranging from the classical unit operations to innovative processes such as the extraction and particle precipitation processes based on supercritical fluids as, for example, in the pharmaceutical technology.Global phase diagrams provide a systematic tool to investigate the phase behaviour of simple as well as complex mixtures. In the early years the method was applied to simple binary fluids mixtures, whereas recent development focuses on complex systems such as polar substances, ionic systems, polymer solutions or blends. In global phase diagrams reduced differences of the molecular parameters of the mixed substances are plotted against each other instead of thermodynamic variables. The boundaries between the different types of phase behaviour can be obtained by calculating high order thermodynamic states which represent transition states between different types of phase behaviour. As a result one obtains a map which provides an overview of the phase behaviour within the validity of a molecular model. Full continuity of the molecular parameters is possible only in theoretical work. In the experimental approach rather a series of discrete systems can be investigated. This limitation canbe overcome by using in multi-component mixtures binaries as pseudo pure substances which allow the effective variation of a molecular property with mole fraction of the pseudo-pure substances. There are two main areas in which progress has been made in recent years: The topological investigation of the complete global phase diagram is necessary for its basic understanding and the investigation of the properties of a certain molecular model. Another direction is the application of the method for the understanding of selected phenomena in phase science which are located in a limited region in the global phase diagram.This International Bunsen Discussion meeting followed a Bunsen colloquium held in March 1999 (Phys. Chem. Chem. Phys., 1999,1, 4225–4336;Phys. Chem. Chem. Phys., 2000,2, 91–95) which was the first international meeting in the area of global phase diagrams. At that meeting the status of the area was reported and further perspectives explored. The progress since then has been reported at the discussion meeting. In this special issue of PCCP several papers presented at the discussion meeting are published. A broad range of experimental and theoretical investigations of phase behaviour are covered. Liquid mixtures, vapour–liquid equilibria and complex ternary systems including solid phases are represented as well as associating fluids and polymer systems. Besides experimental work, theoretical investigations based on analytical models as well as on numerical methods and molecular simulations are included.L. Z. Boshkov (Odessa)U. K. Deiters (Köln)T. Kraska (Köln)R. N. Lichtenthaler (Heidelbe

ISSN:1463-9076     

DOI:10.1039/b201688p

出版商:RSC    

年代:2002

数据来源: RSC