ABSTRACT
MANUEL AGUILAR, JOSÉ LUIS CORTINA, and ANA MARÍA SASTRE Universitat Politècnica de Catalunya, Barcelona, Spain
13.1INTRODUCTION
The role of solvent extraction in analytical chemistry has steadily increased since the mid-1950s as a powerful separation technique applicable both to trace and macro levels of materials. Work in this field has provided the basis for a rich store of analytical methodology characterized by high sensitivity and selectivity as is described in Chapters 2-4. Developments of new extractants and their application to separation of a growing variety of compounds are recognized as an important area of analytical chemistry. Advances in this field over the last 50 years have been reported in a large number of publications, among them several monographs and reviews [1-5]. Because of the great range of concentrations (from weightless trace levels of carrier-free radioisotopes to macro levels of several weight percent of metal ions) for which quantitative separations by solvent extraction are applicable, this technique is equally useful in analytical, preparative, and process chemistry. Solvent extraction has been also used as a separation step in many analytical techniques and methods in response to the new problems posed in many other fields such as medicine, biology, ecology, engineering, etc. Among these, automatic methods of analysis have gained a notable momentum and have motivated the development of a large number of commercial instruments.
