KINETICS AND MECHANISM OF ALKALINE KMNO4 OXIDATION OF D-SORBITOL AND D-DULCITOL
Keywords:
Sugar alcohols, D-sorbitol, D-dulcitol, oxidation, alkaline, potassium permanganate, kinetics, mechanism, activation parametersAbstract
The kinetics and mechanism of alkaline KMnO4 oxidation of D-sorbitol and D-dulcitol were
investigated in this study. The oxidation reactions of sugar alcohols were studied using potassium permanganate
in alkaline medium. The kinetics of the reaction were found to be inverse first order with respect to sugar alcohol
for both substrates, first order each with respect to [KMnO4] and [OH-], and independent of ionic strength for
both substrates investigated. Activation parameters such as activation energy (Ea), enthalpy of activation (ΔH*),
and entropy of activation (ΔS*) were obtained. The oxidation reaction of sugar alcohols was found to exhibit
substrate inhibition due to the formation of a 1:1 manganese-sugar alcohol complex that resists oxidation. A
plausible mechanism was proposed based on kinetic and spectroscopic studies. The proposed mechanism involves
the formation of an intermediate complex between the sugar alcohol and KMnO4 followed by a series of reactions
that ultimately lead to the formation of the final products. The results obtained from this study provide insights
into the kinetics and mechanism of alkaline KMnO4 oxidation of sugar alcohols and contribute to the
understanding of the oxidation of these compounds.
