THE EFFECT OF SURFACE-ACTIVE COMPOUNDS ON CHEMICAL PROCESSES OCCURRING IN AQUATIC ENVIRONMENTS

The active role of amphiphiles on solubilization and transport of pollutants present in aqueous media, as well as their influence on the degradation reactions involving these compounds, have been recently recognized. The partition equilibria of contaminants between water and amphiphilic aggregates, the adsorption of substrates on surfactant-modified suspended particles, the changes in chemical kinetics due to electrostatic and hydrophobic interactions, are at the basis of the observed environmental effects. Moreover, the addition of suitable amphiphiles to aqueous wastes can be exploited for decontamination purposes. In the presence of micelles, organic and inorganic pollutants bound to these aggregates can be removed using ultrafiltration or extraction methods based on phase separation phenomena. Separations using dilute amphiphile solutions can be performed by foam flotation, whereas micellar systems can replace organic solvents in regeneration of exhausted carbon bed adsorbers. The main features and advantages of these surfactant-based procedures are discussed. © 1990.