A New Approach for Determining Stability Constants of Metal Ion Complexes in Aquatic Systems Based on Flow Injection-Ion Exchange-Flame Atomic Absorption Spectrometry Coupling

Abstract

A method based on ion exchange(IE)-atomic absorption spectrometry(AAS) coupled by flow techniques, allowing the determination of formation constants of, at least, the first species of complex systems, in aqueous solution, was developed.

The IE-AAS coupling reduces significantly the number of experimental steps in comparison with IE batch methods, resulting in an important increase in analytical rate. The method is simple both from experimental and computational points of view, making possible its utilization by workers without special expertise in the field of complex equilibria in solution. On the other hand, taking into account mainly the amount of hollow cathode lamps available to date, the developed procedure may be applied, within certain limitations, to the study of many systems whose features prevent the use of traditional approaches.

Key Words:

• ion exchange
• absorption spectrometry
• stability constants