Effect of Micelles on kinetics and mechanism of the oxidation of Serine by acid Permanganate

The oxidation of serine (HORCO 2 H) by acid permanganate was investigated both in the absence and presence of sodium dodecyl sulfate (SDS). It has been observed that the presence of surfactant enhanced the reaction rate. The reaction is first order with respect to [Serine] and [MnO 4 − ]. The reaction is retarded by the hydrogen ion in the absence of SDS but catalyzed in the presence of SDS. The overall rate expression for the reduction of Mn(VII) may be written as\documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm Mn(VII)}]_{{\rm total}}}}{{dt}} = \{ k'_{4f} + k'_{2f} /[{\rm H}^{\rm +}]\} [{\rm Serine]}_{\rm 0} [{\rm Mn(VII)]}_{{\rm total}}. $$\end{document}In the presence of SDS of the rate law is\documentclass{article}\pagestyle{empty}\begin{document}$$- \frac{{d[{\rm Mn(VII)}]_{{\rm total}}}}{{dt}} = \{ k[{\rm H}^{\rm +}] + k'\} [{\rm SDS}][{\rm Serine]}_{\rm 0} [{\rm Mn(VII)]}_{{\rm total}}. $$\end{document}The reaction appears to involve a parallel consecutive reaction mechanism in which Mn(IV) appears as the reaction intermediate. ′ 4 f signifies the rate constant for the reaction path leading to the formation of Mn(IV) from Mn(VII) as reaction intermediate, whereas ′ 2 f signifies the rate constant for the reaction path leading to the reduction of Mn(VII) to Mn(II) without prior formation of Mn(IV). A mechanism satisfying the various kinetic parameters has been proposed.