Application of the electrical conductivity of concentrated electrolyte solutions to industrial process control and design:: from experimental measurement towards prediction through modelling

Different aspects of the conductivity of concentrated electrolyte solutions and their application to design and control of chemical processes are discussed and reviewed, with particular focus on the work of our research group during the last few years. An automated system based on the electrodeless conductivity technique for the measurement of the electrical conductivity of solutions as the basis of a titration strategy is described. The inadequacy of classical calibration methods when high conductivities are to be measured is highlighted and an alternative methodology is proposed. Our measurements on specific concentrated systems of interest in industrial applications and the development of general methodologies to treat experimental conductivity data at constant or varying temperature in order to get comprehensive inter- and extrapolation mathematical models are summarised. Theoretical approaches to explain the variability of conductivity data of electrolyte solutions with the solute concentration as well as the deviations from ideality found at higher concentrations are reviewed and critically evaluated. Solutions of mixed electrolytes are treated in a similar fashion. (C) 2001 Elsevier Science B.V. All rights reserved.