Effect of AOT/Heptane Reverse Micelles on Oxidation of Ferroin by Metaperiodate: Kinetic and Mechanistic Aspects

A kinetic study of the oxidation of Ferroin, [Fe(phen)3]2+ by metaperiodate (IO4-) has been carried out in AOT/heptane reverse micelles by changing W = ([H2O]/[AOT]) and AOT concentration. The reaction order is first order with respect to Ferroin, while zero order with respect to IO4-. The reaction rate is faster in aqueous medium compared to AOT reverse micelles by eight times. The oxidation rate increases with an increase in the value of W (at fixed surfactant concentration, [AOT]) and decreases with AOT concentration. The effect of W on rate is elucidated based on the low dielectric constant of the water pool. Berezin's pseudo-phase model has been applied to explain the effect of AOT on rate.