FACTORS IMPORTANT IN THE SELECTION AND DESCRIPTION OF LIQUID-LIQUID-EXTRACTION PROCEDURES USED IN INORGANIC ANALYTICAL-CHEMISTRY

The report deals with liquid-liquid distribution systems, in which one phase is aqueous, and the distribution of the component can be influe nced in many cases with chemical reactions. The formulas and equations are given, by which the actual distribution ratio of the analyte at g iven conditions and concentrations can be predicted. The conditional e xtraction constants, which are essential for the prediction, can be ca lculated from the real extraction constants and side reaction function s involving the competing chemical reactions, and their equilibrium co nstants. The kinetic aspects of the distribution process, the current analytical techniques, the analytical methods involving liquid-liquid distribution, the fields of applications of liquid-liquid extraction a re briefly introduced. A classification scheme of the extraction syste ms used in analytical chemistry is proposed in which the basic reactio n equations are given, from which the extraction constant, the distrib ution ratio of the analyte can be formulated, and using the formulas, and the necessary equilibrium constant values, the attainable extent o f extraction (fraction extracted) can be estimated.