Effect of surfactant addition on the kinetics of the reaction Fe(bpy)32++S2O82-

Abstract

The oxidation of Fe(bpy) ₃ ²⁺ with S ₂ O ₈ ^2- has been studied in micellar solutions of sodium bis(2-ethylhexyl)sulfosuccinate (AOT), as well as in sodium nitrate and in sodium n-octanesulfonate solutions. In all cases a decrease in the rate constant with increasing salt or surfactant concentration is observed. These results are rationalized using the pseudophase model and, for the surfactant solutions, taking into account the influence of premicellar aggregates.